javax.crypto

Class KeyAgreementSpi

java.lang.Object

javax.crypto.KeyAgreementSpi

Direct Known Subclasses:

KeyAgreementSpi, KeyAgreementSpi, OpenSSLECDHKeyAgreement

public abstract class KeyAgreementSpi
extends Object

The Service Provider Interface (SPI) definition for the KeyAgreement class.

Constructor Summary

Constructors

Constructor and Description
KeyAgreementSpi() Creates a new KeyAgreementSpi instance.

Method Summary

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

Creates a new KeyAgreementSpi instance.

Method Detail

engineDoPhase

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

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

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 abstract byte[] engineGenerateSecret()
                                        throws IllegalStateException

Generates the shared secret.

Returns:

the generated shared secret.

Throws:

IllegalStateException - if this key agreement is not complete.

engineGenerateSecret

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

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

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 abstract SecretKey engineGenerateSecret(String algorithm)
                                           throws IllegalStateException,
                                                  NoSuchAlgorithmException,
                                                  InvalidKeyException

Generates the shared secret.

Parameters:

algorithm - the algorithm to for the SecretKey

Returns:

the shared secret as a SecretKey of the specified algorithm.

Throws:

IllegalStateException - if this key agreement is not complete.

NoSuchAlgorithmException - if the specified algorithm for the secret key does not exists.

InvalidKeyException - if a SecretKey with the specified algorithm cannot be created using the generated shared secret.

engineInit

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

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

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.

engineInit

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

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

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.