com.ibm.crypto.fips.provider

Class DHKeyAgreement

  1. java.lang.Object
  2. extended byjavax.crypto.KeyAgreementSpi
  3. extended bycom.ibm.crypto.fips.provider.DHKeyAgreement
All implemented interfaces:
AlgorithmStatus

  1. public final class DHKeyAgreement
  2. extends javax.crypto.KeyAgreementSpi
  3. implements AlgorithmStatus
This class implements the Diffie-Hellman key agreement protocol between any number of parties.
Version:
1.9, 05/19/03
Author:
Jan Luehe, John Peck

Constructor Summary

Constructor and Description
DHKeyAgreement()
Verify the JCE framework in the constructor.

Method Summary

Modifier and Type Method and Description
  1. protected
  2. java.security.Key
engineDoPhase(java.security.Key key,boolean lastPhase)
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.
  1. protected
  2. byte[]
engineGenerateSecret()
Generates the shared secret and returns it in a new buffer.
  1. protected
  2. int
engineGenerateSecret(byte[] sharedSecret,int offset)
Generates the shared secret, and places it into the buffer sharedSecret, beginning at offset.
  1. protected
  2. javax.crypto.SecretKey
engineGenerateSecret(java.lang.String algorithm)
Creates the shared secret and returns it as a secret key object of the requested algorithm type.
  1. protected
  2. void
engineInit(java.security.Key key,java.security.spec.AlgorithmParameterSpec params,java.security.SecureRandom random)
Initializes this key agreement with the given key, set of algorithm parameters, and source of randomness.
  1. protected
  2. void
engineInit(java.security.Key key,java.security.SecureRandom random)
Initializes this key agreement with the given key and source of randomness.
  1. protected
  2. java.security.Key
internalDoPhase(java.security.Key key,boolean lastPhase)
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.
  1. protected
  2. byte[]
internalGenerateSecret()
Generates the shared secret and returns it in a new buffer.
  1. protected
  2. int
internalGenerateSecret(byte[] sharedSecret,int offset)
Generates the shared secret, and places it into the buffer sharedSecret, beginning at offset.
  1. protected
  2. javax.crypto.SecretKey
internalGenerateSecret(java.lang.String algorithm)
Creates the shared secret and returns it as a secret key object of the requested algorithm type.
  1. protected
  2. void
internalInit(java.security.Key key,java.security.spec.AlgorithmParameterSpec params,java.security.SecureRandom random)
Initializes this key agreement with the given key, set of algorithm parameters, and source of randomness.
  1. boolean
isFipsApproved()
This function allows an application to verify the the algorithm is FIPS approved.
Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

DHKeyAgreement

  1. public DHKeyAgreement()
Verify the JCE framework in the constructor.
Throws:
java.lang.SecurityException - if fails to verify the JCE framework.

Method Detail

isFipsApproved

  1. public boolean isFipsApproved()
This function allows an application to verify the the algorithm is FIPS approved.
Specified by:
See Also:

engineInit

  1. protected void engineInit(java.security.Key key,
  2. java.security.SecureRandom random)
  3. throws java.security.InvalidKeyException
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.

Specified by:
engineInit in class javax.crypto.KeyAgreementSpi
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:
java.security.InvalidKeyException - if the given key is inappropriate for this key agreement, e.g., is of the wrong type or has an incompatible algorithm type.

engineInit

  1. protected void engineInit(java.security.Key key,
  2. java.security.spec.AlgorithmParameterSpec params,
  3. java.security.SecureRandom random)
  4. throws java.security.InvalidKeyException
  5. java.security.InvalidAlgorithmParameterException
Initializes this key agreement with the given key, set of algorithm parameters, and source of randomness.
Specified by:
engineInit in class javax.crypto.KeyAgreementSpi
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:
java.security.InvalidKeyException - if the given key is inappropriate for this key agreement, e.g., is of the wrong type or has an incompatible algorithm type.
java.security.InvalidAlgorithmParameterException - if the given parameters are inappropriate for this key agreement.

internalInit

  1. protected void internalInit(java.security.Key key,
  2. java.security.spec.AlgorithmParameterSpec params,
  3. java.security.SecureRandom random)
  4. throws java.security.InvalidKeyException
  5. java.security.InvalidAlgorithmParameterException
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:
java.security.InvalidKeyException - if the given key is inappropriate for this key agreement, e.g., is of the wrong type or has an incompatible algorithm type.
java.security.InvalidAlgorithmParameterException - if the given parameters are inappropriate for this key agreement.

engineDoPhase

  1. protected java.security.Key engineDoPhase( java.security.Key key,
  2. boolean lastPhase)
  3. throws java.security.InvalidKeyException
  4. java.lang.IllegalStateException
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.
Specified by:
engineDoPhase in class javax.crypto.KeyAgreementSpi
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:
java.security.InvalidKeyException - if the given key is inappropriate for this phase.
java.lang.IllegalStateException - if this key agreement has not been initialized.

internalDoPhase

  1. protected java.security.Key internalDoPhase( java.security.Key key,
  2. boolean lastPhase)
  3. throws java.security.InvalidKeyException
  4. java.lang.IllegalStateException
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:
java.security.InvalidKeyException - if the given key is inappropriate for this phase.
java.lang.IllegalStateException - if this key agreement has not been initialized.

engineGenerateSecret

  1. protected byte[] engineGenerateSecret( )
  2. throws java.lang.IllegalStateException
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.

Specified by:
engineGenerateSecret in class javax.crypto.KeyAgreementSpi
Returns:
the new buffer with the shared secret
Throws:
java.lang.IllegalStateException - if this key agreement has not been completed yet

internalGenerateSecret

  1. protected byte[] internalGenerateSecret( )
  2. throws java.lang.IllegalStateException
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:
java.lang.IllegalStateException - if this key agreement has not been completed yet

engineGenerateSecret

  1. protected int engineGenerateSecret( byte[] sharedSecret,
  2. int offset)
  3. throws java.lang.IllegalStateException
  4. javax.crypto.ShortBufferException
Generates the shared secret, and places it into the buffer sharedSecret, beginning at offset.

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.

Specified by:
engineGenerateSecret in class javax.crypto.KeyAgreementSpi
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:
java.lang.IllegalStateException - if this key agreement has not been completed yet
javax.crypto.ShortBufferException - if the given output buffer is too small to hold the secret

internalGenerateSecret

  1. protected int internalGenerateSecret( byte[] sharedSecret,
  2. int offset)
  3. throws java.lang.IllegalStateException
  4. javax.crypto.ShortBufferException
Generates the shared secret, and places it into the buffer sharedSecret, beginning at offset.

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:
java.lang.IllegalStateException - if this key agreement has not been completed yet
javax.crypto.ShortBufferException - if the given output buffer is too small to hold the secret

engineGenerateSecret

  1. protected javax.crypto.SecretKey engineGenerateSecret( java.lang.String algorithm)
  2. throws java.lang.IllegalStateException
  3. java.security.NoSuchAlgorithmException
  4. java.security.InvalidKeyException
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.

Specified by:
engineGenerateSecret in class javax.crypto.KeyAgreementSpi
Parameters:
algorithm - the requested secret key algorithm
Returns:
the shared secret key
Throws:
java.lang.IllegalStateException - if this key agreement has not been completed yet
java.security.NoSuchAlgorithmException - if the requested secret key algorithm is not available
java.security.InvalidKeyException - 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)

internalGenerateSecret

  1. protected javax.crypto.SecretKey internalGenerateSecret( java.lang.String algorithm)
  2. throws java.lang.IllegalStateException
  3. java.security.NoSuchAlgorithmException
  4. java.security.InvalidKeyException
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:
java.lang.IllegalStateException - if this key agreement has not been completed yet
java.security.NoSuchAlgorithmException - if the requested secret key algorithm is not available
java.security.InvalidKeyException - 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)