ptolemy.actor.lib.security
Class SecretKey

java.lang.Object
  ptolemy.kernel.util.NamedObj
      ptolemy.kernel.InstantiableNamedObj
          ptolemy.kernel.Entity
              ptolemy.kernel.ComponentEntity
                  ptolemy.actor.AtomicActor
                      ptolemy.actor.TypedAtomicActor
                          ptolemy.actor.lib.Source
                              ptolemy.actor.lib.security.SecretKey

All Implemented Interfaces:

java.io.Serializable, java.lang.Cloneable, Actor, Executable, FiringsRecordable, Initializable, TypedActor, Changeable, Debuggable, DebugListener, Derivable, Instantiable, ModelErrorHandler, MoMLExportable, Moveable, Nameable

public class SecretKey
extends Source

Create a secret key and send it on the output.

The secret key is a symmetric key can be used by the SymmetricEncryption and SymmetricDecryption actors. See SymmetricEncryption for a description of symmetric vs. asymmetric algorithms.

This key should be not be visible to users as the security of the encrypted message relies on the secrecy of this key.

This actor relies on the Java Cryptography Architecture (JCA) and Java Cryptography Extension (JCE). See the CryptographyActor documentation for resources about the JCE.

Since:

Ptolemy II 4.0

Version:

$Id: SecretKey.java 57040 2010-01-27 20:52:32Z cxh $

Author:

Christopher Hylands Brooks, Contributor: Rakesh Reddy

See Also:

KeyWriter, SecretKeyReader, Serialized Form

Accepted Rating:

Yellow (cxh)

Proposed Rating:

Green (cxh)

Nested Class Summary

Nested classes/interfaces inherited from class ptolemy.kernel.Entity

Entity.ContainedObjectsIterator

Field Summary

protected java.lang.String	_algorithm The name of the algorithm to be used.
protected int	_keySize The key size to be used when processing information.
protected java.lang.String	_provider The provider to be used for a provider specific implementation.
private javax.crypto.SecretKey	_secretKey
private KeyToken	_secretKeyToken
private boolean	_updateSecretKeyNeeded
StringParameter	algorithm Specify the algorithm to be used to process data.
Parameter	keySize Specify the size of the key to be created.
StringParameter	provider Specify a provider for the given algorithm.

Fields inherited from class ptolemy.actor.lib.Source

output, trigger

Fields inherited from class ptolemy.actor.AtomicActor

_actorFiringListeners, _initializables, _notifyingActorFiring, _stopRequested

Fields inherited from class ptolemy.kernel.util.NamedObj

_changeListeners, _changeLock, _changeRequests, _debugging, _debugListeners, _elementName, _isPersistent, _verbose, _workspace, ATTRIBUTES, CLASSNAME, COMPLETE, CONTENTS, DEEP, FULLNAME, LINKS

Fields inherited from interface ptolemy.actor.Executable

COMPLETED, NOT_READY, STOP_ITERATING

Constructor Summary

SecretKey(CompositeEntity container, java.lang.String name)
Construct an actor with the given container and name.

Method Summary

private void	_updateSecretKey() Update the secret key by calling KeyGenerator.getInstance() with an argument that is created from the values of _algorithm, _provider and _keySize.
void	attributeChanged(Attribute attribute) Override the base class to reinitialize the state if the algorithm, provider, or keysize parameter is changed.
void	fire() Send the key that was generated in initialize() on the output port.
void	initialize() Initialize the key by using the cached values of the parameters.

Methods inherited from class ptolemy.actor.lib.Source

prefire

Methods inherited from class ptolemy.actor.TypedAtomicActor

_addPort, _fireAt, _fireAt, attributeTypeChanged, clone, newPort, typeConstraintList, typeConstraints

Methods inherited from class ptolemy.actor.AtomicActor

_actorFiring, _actorFiring, addActorFiringListener, addInitializable, clone, connectionsChanged, createReceivers, declareDelayDependency, getCausalityInterface, getDirector, getExecutiveDirector, getManager, inputPortList, isFireFunctional, isStrict, iterate, newReceiver, outputPortList, postfire, preinitialize, pruneDependencies, recordFiring, removeActorFiringListener, removeDependency, removeInitializable, setContainer, stop, stopFire, terminate, wrapup

Methods inherited from class ptolemy.kernel.ComponentEntity

_adjustDeferrals, _checkContainer, _getContainedObject, _propagateExistence, getContainer, instantiate, isAtomic, isOpaque, moveDown, moveToFirst, moveToIndex, moveToLast, moveUp, propagateExistence, setName

Methods inherited from class ptolemy.kernel.Entity

_description, _exportMoMLContents, _removePort, _validateSettables, connectedPortList, connectedPorts, containedObjectsIterator, getAttribute, getPort, getPorts, linkedRelationList, linkedRelations, portList, removeAllPorts, setClassDefinition, uniqueName

Methods inherited from class ptolemy.kernel.InstantiableNamedObj

_setParent, exportMoML, getChildren, getElementName, getParent, getPrototypeList, isClassDefinition, isWithinClassDefinition

Methods inherited from class ptolemy.kernel.util.NamedObj

_addAttribute, _adjustOverride, _attachText, _cloneFixAttributeFields, _debug, _debug, _debug, _debug, _debug, _getIndentPrefix, _isMoMLSuppressed, _markContentsDerived, _propagateValue, _recordDecoratedAttributes, _removeAttribute, _splitName, _stripNumericSuffix, addChangeListener, addDebugListener, attributeList, attributeList, deepContains, depthInHierarchy, description, description, event, executeChangeRequests, exportMoML, exportMoML, exportMoML, exportMoML, exportMoMLPlain, getAttribute, getAttributes, getChangeListeners, getClassName, getDecoratorAttribute, getDecoratorAttributes, getDerivedLevel, getDerivedList, getDisplayName, getFullName, getModelErrorHandler, getName, getName, getSource, handleModelError, isDeferringChangeRequests, isOverridden, isPersistent, lazyContainedObjectsIterator, message, propagateValue, propagateValues, removeChangeListener, removeDebugListener, requestChange, setClassName, setDeferringChangeRequests, setDerivedLevel, setDisplayName, setModelErrorHandler, setPersistent, setSource, sortContainedObjects, toplevel, toString, validateSettables, workspace

Methods inherited from class java.lang.Object

equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

Methods inherited from interface ptolemy.actor.Actor

createReceivers, getCausalityInterface, getDirector, getExecutiveDirector, getManager, inputPortList, newReceiver, outputPortList

Methods inherited from interface ptolemy.actor.Executable

isFireFunctional, isStrict, iterate, postfire, stop, stopFire, terminate

Methods inherited from interface ptolemy.actor.Initializable

addInitializable, preinitialize, removeInitializable, wrapup

Methods inherited from interface ptolemy.kernel.util.Nameable

description, getContainer, getDisplayName, getFullName, getName, getName, setName

Methods inherited from interface ptolemy.kernel.util.Derivable

getDerivedLevel, getDerivedList, propagateValue

Field Detail

algorithm

public StringParameter algorithm

Specify the algorithm to be used to process data. The algorithm is specified as a string. The algorithms are limited to those implemented by providers using the Java JCE which are found on the system. The initial default is "DES".

provider

public StringParameter provider

Specify a provider for the given algorithm. Takes the algorithm name as a string. The default value is "SystemDefault" which allows the system chooses the provider based on the JCE architecture.

keySize

public Parameter keySize

Specify the size of the key to be created. The key size is an integer value representing the number of bits in the key. The initial default depends on the algorithm that is selected, not all algorithms use keySize.

DSA is the most common algorithm that uses keySize, the Sun documentation says: "The length, in bits, of the modulus p. This must range from 512 to 1024, and must be a multiple of 64. The default keysize is 1024." Refer to http://java.sun.com/j2se/1.4.2/docs/guide/security/CryptoSpec.html#AppB for a list of possible key sizes for certain algorithms. The initial default is 1024.

_algorithm

protected java.lang.String _algorithm

The name of the algorithm to be used.

_keySize

protected int _keySize

The key size to be used when processing information.

_provider

protected java.lang.String _provider

The provider to be used for a provider specific implementation.

_secretKey

private javax.crypto.SecretKey _secretKey

_secretKeyToken

private KeyToken _secretKeyToken

_updateSecretKeyNeeded

private boolean _updateSecretKeyNeeded

Constructor Detail

SecretKey

public SecretKey(CompositeEntity container,
                 java.lang.String name)
          throws NameDuplicationException,
                 IllegalActionException

Construct an actor with the given container and name. The Java virtual machine is queried for algorithm and provider choices and these choices are added to the appropriate parameters.

Parameters:

container - The container.

name - The name of this actor.

Throws:

IllegalActionException - If the actor cannot be contained by the proposed container.

NameDuplicationException - If the container already has an actor with this name.

Method Detail

attributeChanged

public void attributeChanged(Attribute attribute)
                      throws IllegalActionException

Override the base class to reinitialize the state if the algorithm, provider, or keysize parameter is changed.

Overrides:

attributeChanged in class NamedObj

Parameters:

attribute - The attribute that changed.

Throws:

IllegalActionException - Not thrown in this base class.

fire

public void fire()
          throws IllegalActionException

Send the key that was generated in initialize() on the output port.

Specified by:

fire in interface Executable

Overrides:

fire in class Source

Throws:

IllegalActionException - If thrown by base class.

initialize

public void initialize()
                throws IllegalActionException

Initialize the key by using the cached values of the parameters.

Specified by:

initialize in interface Initializable

Overrides:

initialize in class AtomicActor

Throws:

IllegalActionException - If thrown by base class or if the algorithm is not found, or if the padding scheme is illegal, or if the specified provider does not exist.

_updateSecretKey

private void _updateSecretKey()
                       throws IllegalActionException

Update the secret key by calling KeyGenerator.getInstance() with an argument that is created from the values of _algorithm, _provider and _keySize.

Throws:

IllegalActionException