Module java.base
Package java.security

Enum Class DrbgParameters.Capability

java.lang.Object
java.lang.Enum<DrbgParameters.Capability>
java.security.DrbgParameters.Capability
All Implemented Interfaces:
Serializable, Comparable<DrbgParameters.Capability>, Constable
Enclosing class:
DrbgParameters
public static enum DrbgParameters.Capability extends Enum<DrbgParameters.Capability>
The reseedable and prediction resistance capabilities of a DRBG.

When this object is passed to a SecureRandom.getInstance() call, it is the requested minimum capability. When it's returned from SecureRandom.getParameters(), it is the effective capability.

Please note that while the Instantiate_function defined in NIST SP 800-90Ar1 only includes a prediction_resistance_flag parameter, the Capability type includes an extra value RESEED_ONLY because reseeding is an optional function. If NONE is used in an Instantiation object in calling the SecureRandom.getInstance method, the returned DRBG instance is not guaranteed to support reseeding. If RESEED_ONLY or PR_AND_RESEED is used, the instance must support reseeding.

The table below lists possible effective values if a certain capability is requested, i.e. 

 Capability requested = ...;
 SecureRandom s = SecureRandom.getInstance("DRBG",
         DrbgParameters(-1, requested, null));
 Capability effective = ((DrbgParametes.Initiate) s.getParameters())
         .getCapability();
requested and effective capabilities
Requested Value Possible Effective Values
NONENONE, RESEED_ONLY, PR_AND_RESEED
RESEED_ONLYRESEED_ONLY, PR_AND_RESEED
PR_AND_RESEEDPR_AND_RESEED

A DRBG implementation supporting prediction resistance must also support reseeding.

Since:
9

  • Enum Constant Details

  • Method Details

    • values

      public static DrbgParameters.Capability[] values()
      Returns an array containing the constants of this enum class, in the order they are declared.
      Returns:
      an array containing the constants of this enum class, in the order they are declared

    • valueOf

      public static DrbgParameters.Capability valueOf(String name)
      Returns the enum constant of this class with the specified name. The string must match exactly an identifier used to declare an enum constant in this class. (Extraneous whitespace characters are not permitted.)
      Parameters:
      name - the name of the enum constant to be returned.
      Returns:
      the enum constant with the specified name
      Throws:
      IllegalArgumentException - if this enum class has no constant with the specified name
      NullPointerException - if the argument is null

    • supportsReseeding

      public boolean supportsReseeding()
      Returns whether this capability supports reseeding.
      Returns:
      true for PR_AND_RESEED and RESEED_ONLY, and false for NONE

    • supportsPredictionResistance

      public boolean supportsPredictionResistance()
      Returns whether this capability supports prediction resistance.
      Returns:
      true for PR_AND_RESEED, and false for RESEED_ONLY and NONE