Module java.base
Package javax.crypto

Interface KEMSpi.DecapsulatorSpi

Enclosing interface:
KEMSpi
public static interface KEMSpi.DecapsulatorSpi
The KEM decapsulator implementation, generated by KEMSpi.engineNewDecapsulator(java.security.PrivateKey, java.security.spec.AlgorithmParameterSpec) on the KEM receiver side.
API Note:
This interface is defined in Java SE 17 Maintenance Release 1.
Since:
17
See Also:

  • Method Summary

    Modifier and Type
    Method
    Description
    SecretKey
    engineDecapsulate(byte[] encapsulation, int from, int to, String algorithm)
    The key decapsulation function.
    int
    engineEncapsulationSize()
    Returns the size of the key encapsulation message.
    int
    engineSecretSize()
    Returns the size of the shared secret.

  • Method Details

    • engineDecapsulate

      SecretKey engineDecapsulate(byte[] encapsulation, int from, int to, String algorithm) throws DecapsulateException
      The key decapsulation function.

      An invocation of this method recovers the secret key from the key encapsulation message.

      An implementation must support the case where from is 0, to is the same as the return value of secretSize(), and algorithm is "Generic".

      Parameters:
      encapsulation - the key encapsulation message from the sender. The size must be equal to the value returned by engineEncapsulationSize() ()}, or a DecapsulateException must be thrown.
      from - the initial index of the shared secret byte array to be returned, inclusive
      to - the final index of the shared secret byte array to be returned, exclusive
      algorithm - the algorithm name for the secret key that is returned
      Returns:
      a portion of the shared secret as a SecretKey with the specified algorithm
      Throws:
      DecapsulateException - if an error occurs during the decapsulation process
      IndexOutOfBoundsException - if from < 0, from > to, or to > secretSize()
      NullPointerException - if encapsulation or algorithm is null
      UnsupportedOperationException - if the combination of from, to, and algorithm is not supported by the decapsulator
      See Also:

    • engineSecretSize

      int engineSecretSize()
      Returns the size of the shared secret.
      Returns:
      the size of the shared secret as a finite non-negative integer
      See Also:

    • engineEncapsulationSize

      int engineEncapsulationSize()
      Returns the size of the key encapsulation message.
      Returns:
      the size of the key encapsulation message as a finite non-negative integer
      See Also: