KeyAgreementSpi (Java SE 11 & JDK 11 ) (original) (raw)

Constructor Detail

 * #### KeyAgreementSpi  
 public KeyAgreementSpi()

Method Detail

* #### engineInit  
protected abstract void engineInit([Key](../../java/security/Key.html "interface in java.security") key,  
                                   [SecureRandom](../../java/security/SecureRandom.html "class in java.security") random)  
                            throws [InvalidKeyException](../../java/security/InvalidKeyException.html "class in java.security")  
Initializes this key agreement with the given key and source of randomness. The given key is required to contain all the algorithm parameters required for this key agreement.  
 If the key agreement algorithm requires random bytes, it gets them from the given source of randomness, `random`. However, if the underlying algorithm implementation does not require any random bytes,`random` is ignored.  
Parameters:  
`key` \- the party's private information. For example, in the case of the Diffie-Hellman key agreement, this would be the party's own Diffie-Hellman private key.  
`random` \- the source of randomness  
Throws:  
`[InvalidKeyException](../../java/security/InvalidKeyException.html "class in java.security")` \- if the given key is inappropriate for this key agreement, e.g., is of the wrong type or has an incompatible algorithm type.  
* #### engineInit  
protected abstract void engineInit([Key](../../java/security/Key.html "interface in java.security") key,  
                                   [AlgorithmParameterSpec](../../java/security/spec/AlgorithmParameterSpec.html "interface in java.security.spec") params,  
                                   [SecureRandom](../../java/security/SecureRandom.html "class in java.security") random)  
                            throws [InvalidKeyException](../../java/security/InvalidKeyException.html "class in java.security"),  
                                   [InvalidAlgorithmParameterException](../../java/security/InvalidAlgorithmParameterException.html "class in java.security")  
Initializes this key agreement with the given key, set of algorithm parameters, and source of randomness.  
Parameters:  
`key` \- the party's private information. For example, in the case of the Diffie-Hellman key agreement, this would be the party's own Diffie-Hellman private key.  
`params` \- the key agreement parameters  
`random` \- the source of randomness  
Throws:  
`[InvalidKeyException](../../java/security/InvalidKeyException.html "class in java.security")` \- if the given key is inappropriate for this key agreement, e.g., is of the wrong type or has an incompatible algorithm type.  
`[InvalidAlgorithmParameterException](../../java/security/InvalidAlgorithmParameterException.html "class in java.security")` \- if the given parameters are inappropriate for this key agreement.  
* #### engineDoPhase  
protected abstract [Key](../../java/security/Key.html "interface in java.security") engineDoPhase([Key](../../java/security/Key.html "interface in java.security") key,  
                                     boolean lastPhase)  
                              throws [InvalidKeyException](../../java/security/InvalidKeyException.html "class in java.security"),  
                                     [IllegalStateException](../../java/lang/IllegalStateException.html "class in java.lang")  
Executes the next phase of this key agreement with the given key that was received from one of the other parties involved in this key agreement.  
Parameters:  
`key` \- the key for this phase. For example, in the case of Diffie-Hellman between 2 parties, this would be the other party's Diffie-Hellman public key.  
`lastPhase` \- flag which indicates whether or not this is the last phase of this key agreement.  
Returns:  
the (intermediate) key resulting from this phase, or null if this phase does not yield a key  
Throws:  
`[InvalidKeyException](../../java/security/InvalidKeyException.html "class in java.security")` \- if the given key is inappropriate for this phase.  
`[IllegalStateException](../../java/lang/IllegalStateException.html "class in java.lang")` \- if this key agreement has not been initialized.  
* #### engineGenerateSecret  
protected abstract byte[] engineGenerateSecret()  
                                        throws [IllegalStateException](../../java/lang/IllegalStateException.html "class in java.lang")  
Generates the shared secret and returns it in a new buffer.  
This method resets this `KeyAgreementSpi` object, so that it can be reused for further key agreements. Unless this key agreement is reinitialized with one of the `engineInit` methods, the same private information and algorithm parameters will be used for subsequent key agreements.  
Returns:  
the new buffer with the shared secret  
Throws:  
`[IllegalStateException](../../java/lang/IllegalStateException.html "class in java.lang")` \- if this key agreement has not been completed yet  
* #### engineGenerateSecret  
protected abstract int engineGenerateSecret(byte[] sharedSecret,  
                                            int offset)  
                                     throws [IllegalStateException](../../java/lang/IllegalStateException.html "class in java.lang"),  
                                            [ShortBufferException](ShortBufferException.html "class in javax.crypto")  
Generates the shared secret, and places it into the buffer`sharedSecret`, beginning at `offset` inclusive.  
If the `sharedSecret` buffer is too small to hold the result, a `ShortBufferException` is thrown. In this case, this call should be repeated with a larger output buffer.  
This method resets this `KeyAgreementSpi` object, so that it can be reused for further key agreements. Unless this key agreement is reinitialized with one of the `engineInit` methods, the same private information and algorithm parameters will be used for subsequent key agreements.  
Parameters:  
`sharedSecret` \- the buffer for the shared secret  
`offset` \- the offset in `sharedSecret` where the shared secret will be stored  
Returns:  
the number of bytes placed into `sharedSecret`  
Throws:  
`[IllegalStateException](../../java/lang/IllegalStateException.html "class in java.lang")` \- if this key agreement has not been completed yet  
`[ShortBufferException](ShortBufferException.html "class in javax.crypto")` \- if the given output buffer is too small to hold the secret  
* #### engineGenerateSecret  
protected abstract [SecretKey](SecretKey.html "interface in javax.crypto") engineGenerateSecret([String](../../java/lang/String.html "class in java.lang") algorithm)  
                                           throws [IllegalStateException](../../java/lang/IllegalStateException.html "class in java.lang"),  
                                                  [NoSuchAlgorithmException](../../java/security/NoSuchAlgorithmException.html "class in java.security"),  
                                                  [InvalidKeyException](../../java/security/InvalidKeyException.html "class in java.security")  
Creates the shared secret and returns it as a secret key object of the requested algorithm type.  
This method resets this `KeyAgreementSpi` object, so that it can be reused for further key agreements. Unless this key agreement is reinitialized with one of the `engineInit` methods, the same private information and algorithm parameters will be used for subsequent key agreements.  
Parameters:  
`algorithm` \- the requested secret key algorithm  
Returns:  
the shared secret key  
Throws:  
`[IllegalStateException](../../java/lang/IllegalStateException.html "class in java.lang")` \- if this key agreement has not been completed yet  
`[NoSuchAlgorithmException](../../java/security/NoSuchAlgorithmException.html "class in java.security")` \- if the requested secret key algorithm is not available  
`[InvalidKeyException](../../java/security/InvalidKeyException.html "class in java.security")` \- if the shared secret key material cannot be used to generate a secret key of the requested algorithm type (e.g., the key material is too short)