ptolemy.actor.lib.security
Class CryptographyActor

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.security.CryptographyActor

All Implemented Interfaces:

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

Direct Known Subclasses:

CipherActor

public abstract class CryptographyActor
extends TypedAtomicActor

A base class for cryptographic actors.

Cryptographic actors are actors that perform encryption or decryption or generate signatures of data.

Actors extending this class take in an unsigned byte array at the input, process the data based on the algorithm parameter and send an unsigned byte array to the output. The algorithms that maybe implemented are limited those that are implemented by "providers" following the Java Cryptography Extension (JCE) specifications and installed on the machine being run. If a provider specific instance of an algorithm is needed, the provider may be specified in the provider parameter. The keySize also allows implementations of algorithms using various key sizes.

Concrete actors derived from this base class must include a _process(byte[]) method that processes the data appropriately. The _process() method is called by CryptographyActor.fire(). This class takes care of basic initialization of the algorithm and provider parameters for use by the subclasses.

This actor relies on the Java Cryptography Architecture (JCA) and Java Cryptography Extension (JCE).
Information about JCA can be found at http://java.sun.com/j2se/1.4.2/docs/guide/security/CryptoSpec.html.
Information about JCE can be found at http://java.sun.com/products/jce/.
The Java 1.2 security tutorial can be found at http://java.sun.com/docs/books/tutorial/security1.2/index.html
Another Java security tutorial can be found at http://developer.java.sun.com/developer/onlineTraining/Security/Fundamentals/index.html

Since:

Ptolemy II 4.0

Version:

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

Author:

Christopher Hylands Brooks, Contributor: Rakesh Reddy

See Also:

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.
StringParameter	algorithm Specify the algorithm to be used to process data.
TypedIOPort	input The input port.
Parameter	keySize Specify the size of the key to be created.
TypedIOPort	output The output port.
StringParameter	provider Specify a provider for the given algorithm.

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

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

Method Summary

protected abstract byte[]	_process(byte[] dataBytes) Process the input data based on parameter specifications.
void	attributeChanged(Attribute attribute) Override the base class to reinitialize the state if the algorithm, keySize, or provider parameter is changed.
void	fire() Read data from the from the input and process the data based on the algorithm, and provider by calling _process(byte []).

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, initialize, inputPortList, isFireFunctional, isStrict, iterate, newReceiver, outputPortList, postfire, prefire, 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, prefire, stop, stopFire, terminate

Methods inherited from interface ptolemy.actor.Initializable

addInitializable, initialize, 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 Java virtual machine. The initial default is the first value returned by java.security.Security.getAlgorithms();

input

public TypedIOPort input

The input port. The type of this port is unsigned byte array. Data is read in on this port, processed by the _process() method during fire() and passed to the output port.

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. In addition, only certain keySizes may work with certain algorithms, see the documentation for the algorithm you are using.

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.

output

public TypedIOPort output

The output port. The type of this port is unsigned byte array. This port sends out the processed data received from the input port.

provider

public StringParameter provider

Specify a provider for the given algorithm. The default value is "SystemDefault" which allows the system to choose the provider based on the JCE architecture.

_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.

Constructor Detail

CryptographyActor

public CryptographyActor(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, keySize, or provider 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

Read data from the from the input and process the data based on the algorithm, and provider by calling _process(byte []). The transformed data is then sent to the output port.

Specified by:

fire in interface Executable

Overrides:

fire in class AtomicActor

Throws:

IllegalActionException - If thrown by the base class or if there is a problem processing the data.

_process

protected abstract byte[] _process(byte[] dataBytes)
                            throws IllegalActionException

Process the input data based on parameter specifications. Subclasses should process the data using one of the signature or cipher classes provided in the JCA or JCE.

Parameters:

dataBytes - The data to be processed.

Returns:

The processed data.

Throws:

IllegalActionException - Not thrown in this base class