RC4 Class

Properties Methods Events Config Settings Errors

Encrypt and decrypt data with the RC4 (ARC4 / ARCFOUR ) stream cipher.

Syntax

ipworksencrypt.Rc4

Remarks

The RC4 component is used to encrypt and decrypt data with the RC4 (ARC4 / ARCFOUR ) stream cipher.

To begin simply specify the data you wish to encrypt or decrypt.

Input and Output Properties

The class will determine the source and destination of the input and output based on which properties are set.

The order in which the input properties are checked is as follows:

SetInputStream
InputFile
InputMessage

When a valid source is found the search stops. The order in which the output properties are checked is as follows:

SetOutputStream
OutputFile
OutputMessage: The output data is written to this property if no other destination is specified.

When using streams you may need to additionally set CloseInputStreamAfterProcessing or CloseOutputStreamAfterProcessing.

Before encrypting you must have a valid Key and IV. There are a few options available to you in regards to key management. The easiest option is to simply set KeyPassword. When KeyPassword is set the component will automatically create a Key and IV using the PKCS5 password digest algorithm. This means there is only one value you need to keep track of.

If you wish to have more control over the Key and IV values you may specify the properties yourself. If IV is left empty, one will be created for you when you call Encrypt or Decrypt.

A simple example: Component.InputFile = "C:\MyFile.txt"; Component.OutputFile = "C:\Encrypted.txt"; Component.KeyPassword = "password"; Component.Encrypt();

Property List

The following is the full list of the properties of the class with short descriptions. Click on the links for further details.


InputFile	The file to process.
InputMessage	The message to process.
IV	The initialization vector (IV).
Key	The secret key for the symmetric algorithm.
KeyPassword	A password to generate the Key and IV .
OutputFile	The output file when encrypting or decrypting.
OutputMessage	The output message after processing.
Overwrite	Indicates whether or not the class should overwrite files.
UseHex	Whether input or output is hex encoded.

Method List

The following is the full list of the methods of the class with short descriptions. Click on the links for further details.


Config	Sets or retrieves a configuration setting.
Decrypt	Decrypts the data.
DecryptBlock	Decrypts a block and returns the decrypted data.
Encrypt	Encrypts the data.
EncryptBlock	Encrypts data and returns the encrypted block.
Reset	Resets the class.
SetInputStream	Sets the stream from which the class will read data to encrypt or decrypt.
SetOutputStream	Sets the stream to which the class will write encrypted or decrypted data.

Event List

The following is the full list of the events fired by the class with short descriptions. Click on the links for further details.


Error	Fired when information is available about errors during data delivery.
Progress	Fired as progress is made.

Config Settings

The following is a list of config settings for the class with short descriptions. Click on the links for further details.


CloseInputStreamAfterProcessing	Determines whether or not the input stream is closed after processing.
CloseOutputStreamAfterProcessing	Determines whether or not the output stream is closed after processing.
KeySize	The size, in bits, of secret key for the symmetric algorithm.
BuildInfo	Information about the product's build.
GUIAvailable	Whether or not a message loop is available for processing events.
LicenseInfo	Information about the current license.
MaskSensitive	Whether sensitive data is masked in log messages.
UseDaemonThreads	Whether threads created by the class are daemon threads.
UseInternalSecurityAPI	Whether or not to use the system security libraries or an internal implementation.

InputFile Property (RC4 Class)

The file to process.

Syntax


public String getInputFile();


public void setInputFile(String inputFile);

Default Value

Remarks

This property specifies the file to be processed. Set this property to the full or relative path to the file which will be processed.

Input and Output Properties

The class will determine the source and destination of the input and output based on which properties are set.

The order in which the input properties are checked is as follows:

SetInputStream
InputFile
InputMessage

When a valid source is found the search stops. The order in which the output properties are checked is as follows:

SetOutputStream
OutputFile
OutputMessage: The output data is written to this property if no other destination is specified.

When using streams you may need to additionally set CloseInputStreamAfterProcessing or CloseOutputStreamAfterProcessing.

InputMessage Property (RC4 Class)

The message to process.

Syntax


public byte[] getInputMessage();


public void setInputMessage(byte[] inputMessage);

Default Value

Remarks

This property specifies the message to be processed.

Input and Output Properties

The class will determine the source and destination of the input and output based on which properties are set.

The order in which the input properties are checked is as follows:

SetInputStream
InputFile
InputMessage

When a valid source is found the search stops. The order in which the output properties are checked is as follows:

SetOutputStream
OutputFile
OutputMessage: The output data is written to this property if no other destination is specified.

When using streams you may need to additionally set CloseInputStreamAfterProcessing or CloseOutputStreamAfterProcessing.

IV Property (RC4 Class)

The initialization vector (IV).

Syntax


public byte[] getIV();


public void setIV(byte[] IV);

Default Value

Remarks

This property specifies the initialization vector (IV). By default this property is empty and the class will automatically generate a new IV value if KeyPassword or Key is set before Encrypt or EncryptBlock is called. The size of the IV property must be equal to the BlockSize divided by 8.

Key Property (RC4 Class)

The secret key for the symmetric algorithm.

Syntax


public byte[] getKey();


public void setKey(byte[] key);

Default Value

Remarks

This secret key is used both for encryption and decryption. The secret key should be known only to the sender and the receiver. The legal key size varies depending on the algorithm.

If this property is left empty and KeyPassword is specified, a Key value will be generated by the class as necessary.

Legal Key and Block Sizes (in bits)


	AES	Rijndael	CAST	DES	IDEA	RC2	RC4	TripleDES	Blowfish	Twofish	TEA
Minimum Key Size	128	128	112	64	128	112	112	128	112	128	128
Maximum Key Size	256	256	128	64	128	128	2048	192	448	256	128
Key Size Step	64	64	8	0	0	8	8	64	1	8	0
Block Size	128	128/192/256	64	64	64	64	N/A	64	64	128	64*

Note: When using TEA if Algorithm is set to XXTEA valid block sizes are 64 + n * 32. Where n is any positive integer.

The default KeySize is the Maximum Key Size.

KeyPassword Property (RC4 Class)

A password to generate the Key and IV .

Syntax


public String getKeyPassword();


public void setKeyPassword(String keyPassword);

Default Value

Remarks

When this property is set the class will calculate values for Key and IV using the PKCS5 password digest algorithm. This provides a simpler alternative to creating and managing Key and IV values directly.

The size of the Key generated is dependent on the value of KeySize.

OutputFile Property (RC4 Class)

The output file when encrypting or decrypting.

Syntax


public String getOutputFile();


public void setOutputFile(String outputFile);

Default Value

Remarks

This property specifies the file to which the output will be written when Encrypt or Decrypt is called. This may be set to an absolute or relative path.

This property is only applicable to Encrypt and Decrypt.

Input and Output Properties

The class will determine the source and destination of the input and output based on which properties are set.

The order in which the input properties are checked is as follows:

SetInputStream
InputFile
InputMessage

When a valid source is found the search stops. The order in which the output properties are checked is as follows:

SetOutputStream
OutputFile
OutputMessage: The output data is written to this property if no other destination is specified.

When using streams you may need to additionally set CloseInputStreamAfterProcessing or CloseOutputStreamAfterProcessing.

OutputMessage Property (RC4 Class)

The output message after processing.

Syntax


public byte[] getOutputMessage();

Default Value

Remarks

This property will be populated with the output from the operation if OutputFile and SetOutputStream are not set.

Input and Output Properties

The class will determine the source and destination of the input and output based on which properties are set.

The order in which the input properties are checked is as follows:

SetInputStream
InputFile
InputMessage

When a valid source is found the search stops. The order in which the output properties are checked is as follows:

SetOutputStream
OutputFile
OutputMessage: The output data is written to this property if no other destination is specified.

When using streams you may need to additionally set CloseInputStreamAfterProcessing or CloseOutputStreamAfterProcessing.

This property is read-only and not available at design time.

Overwrite Property (RC4 Class)

Indicates whether or not the class should overwrite files.

Syntax


public boolean isOverwrite();


public void setOverwrite(boolean overwrite);

Default Value

False

Remarks

This property indicates whether or not the class will overwrite OutputFile. If Overwrite is False, an error will be thrown whenever OutputFile exists before an operation. The default value is False.

UseHex Property (RC4 Class)

Whether input or output is hex encoded.

Syntax


public boolean isUseHex();


public void setUseHex(boolean useHex);

Default Value

False

Remarks

This property specifies whether the encrypted data is hex encoded.

If set to True, when Encrypt is called the class will perform the encryption as normal and then hex encode the output. OutputMessage or OutputFile will hold hex encoded data.

If set to True, when Decrypt is called the class will expect InputMessage or InputFile to hold hex encoded data. The class will then hex decode the data and perform decryption as normal.

Config Method (Rc4 Class)

Sets or retrieves a configuration setting.

Syntax

public String config(String configurationString);

Remarks

Config is a generic method available in every class. It is used to set and retrieve configuration settings for the class.

These settings are similar in functionality to properties, but they are rarely used. In order to avoid "polluting" the property namespace of the class, access to these internal properties is provided through the Config method.

To set a configuration setting named PROPERTY, you must call Config("PROPERTY=VALUE"), where VALUE is the value of the setting expressed as a string. For boolean values, use the strings "True", "False", "0", "1", "Yes", or "No" (case does not matter).

To read (query) the value of a configuration setting, you must call Config("PROPERTY"). The value will be returned as a string.

Decrypt Method (Rc4 Class)

Decrypts the data.

Syntax

public void decrypt();

Remarks

This method will decrypt the specified data. The following properties are applicable:

IV (required)
Key (required)
CipherMode
PaddingMode

Note that CipherMode must be set to the same value used during encryption or the results may be unexpected. If the CipherMode value does not match the value used during encryption the operation may succeed but the decrypted data may not be correct.

Input and Output Properties

The class will determine the source and destination of the input and output based on which properties are set.

The order in which the input properties are checked is as follows:

SetInputStream
InputFile
InputMessage

When a valid source is found the search stops. The order in which the output properties are checked is as follows:

SetOutputStream
OutputFile
OutputMessage: The output data is written to this property if no other destination is specified.

When using streams you may need to additionally set CloseInputStreamAfterProcessing or CloseOutputStreamAfterProcessing.

DecryptBlock Method (Rc4 Class)

Decrypts a block and returns the decrypted data.

Syntax

public byte[] decryptBlock(byte[] inputBuffer);

Remarks

This method decrypted the data specified by InputBuffer and returns the decrypted data.

Encrypt Method (Rc4 Class)

Encrypts the data.

Syntax

public void encrypt();

Remarks

This method will encrypt the specified data. The following properties are applicable:

IV (required)
Key (required)
PaddingMode
CipherMode

Input and Output Properties

The class will determine the source and destination of the input and output based on which properties are set.

The order in which the input properties are checked is as follows:

SetInputStream
InputFile
InputMessage

When a valid source is found the search stops. The order in which the output properties are checked is as follows:

SetOutputStream
OutputFile
OutputMessage: The output data is written to this property if no other destination is specified.

When using streams you may need to additionally set CloseInputStreamAfterProcessing or CloseOutputStreamAfterProcessing.

EncryptBlock Method (Rc4 Class)

Encrypts data and returns the encrypted block.

Syntax

public byte[] encryptBlock(byte[] inputBuffer);

Remarks

This method encrypts the data specified by InputBuffer and returns the encrypted block.

Reset Method (Rc4 Class)

Resets the class.

Syntax

public void reset();

Remarks

When called, the class will reset all of its properties to their default values.

SetInputStream Method (Rc4 Class)

Sets the stream from which the class will read data to encrypt or decrypt.

Syntax

public void setInputStream(java.io.InputStream inputStream);

Remarks

This method sets the stream from which the class will read data to encrypt or decrypt.

Input and Output Properties

The class will determine the source and destination of the input and output based on which properties are set.

The order in which the input properties are checked is as follows:

SetInputStream
InputFile
InputMessage

When a valid source is found the search stops. The order in which the output properties are checked is as follows:

SetOutputStream
OutputFile
OutputMessage: The output data is written to this property if no other destination is specified.

When using streams you may need to additionally set CloseInputStreamAfterProcessing or CloseOutputStreamAfterProcessing.

SetOutputStream Method (Rc4 Class)

Sets the stream to which the class will write encrypted or decrypted data.

Syntax

public void setOutputStream(java.io.OutputStream outputStream);

Remarks

This method sets the stream to which the class will write encrypted or decrypted data.

Input and Output Properties

The class will determine the source and destination of the input and output based on which properties are set.

The order in which the input properties are checked is as follows:

SetInputStream
InputFile
InputMessage

When a valid source is found the search stops. The order in which the output properties are checked is as follows:

SetOutputStream
OutputFile
OutputMessage: The output data is written to this property if no other destination is specified.

When using streams you may need to additionally set CloseInputStreamAfterProcessing or CloseOutputStreamAfterProcessing.

Error Event (Rc4 Class)

Fired when information is available about errors during data delivery.

Syntax

public class DefaultRc4EventListener implements Rc4EventListener {
  ...
  public void error(Rc4ErrorEvent e) {}
  ...
}

public class Rc4ErrorEvent {
  public int errorCode;
  public String description;
}

Remarks

The Error event is fired in case of exceptional conditions during message processing. Normally the class throws an exception.

The ErrorCode parameter contains an error code, and the Description parameter contains a textual description of the error. For a list of valid error codes and their descriptions, please refer to the Error Codes section.

Progress Event (Rc4 Class)

Fired as progress is made.

Syntax

public class DefaultRc4EventListener implements Rc4EventListener {
  ...
  public void progress(Rc4ProgressEvent e) {}
  ...
}

public class Rc4ProgressEvent {
  public long bytesProcessed;
  public int percentProcessed;
}

Remarks

This event is fired automatically as data is processed by the class.

The PercentProcessed parameter indicates the current status of the operation.

The BytesProcessed parameter holds the total number of bytes processed so far.

Config Settings (Rc4 Class)

The class accepts one or more of the following configuration settings. Configuration settings are similar in functionality to properties, but they are rarely used. In order to avoid "polluting" the property namespace of the class, access to these internal properties is provided through the Config method.

RC4 Config Settings

CloseInputStreamAfterProcessing: Determines whether or not the input stream is closed after processing.

Determines whether or not the input stream set by SetInputStream is closed after processing is complete. The default value is True.

CloseOutputStreamAfterProcessing: Determines whether or not the output stream is closed after processing.

Determines whether or not the output stream set by SetOutputStream is closed after processing is complete. The default value is True.

KeySize: The size, in bits, of secret key for the symmetric algorithm.

The legal key sizes vary depending on the algorithm. The KeySize and BlockSize configuration settings may be set to specify the key and block size (in bits).

This setting is only applicable when KeyPassword is specified.

Note that when using the EzCrypt class, KeySize should be set after setting the Algorithm property.

Base Config Settings

BuildInfo: Information about the product's build.

When queried, this setting will return a string containing information about the product's build.

GUIAvailable: Whether or not a message loop is available for processing events.

In a GUI-based application, long-running blocking operations may cause the application to stop responding to input until the operation returns. The class will attempt to discover whether or not the application has a message loop and, if one is discovered, it will process events in that message loop during any such blocking operation.

In some non-GUI applications, an invalid message loop may be discovered that will result in errant behavior. In these cases, setting GUIAvailable to false will ensure that the class does not attempt to process external events.

LicenseInfo: Information about the current license.

When queried, this setting will return a string containing information about the license this instance of a class is using. It will return the following information:

Product: The product the license is for.
Product Key: The key the license was generated from.
License Source: Where the license was found (e.g., RuntimeLicense, License File).
License Type: The type of license installed (e.g., Royalty Free, Single Server).
Last Valid Build: The last valid build number for which the license will work.

MaskSensitive: Whether sensitive data is masked in log messages.

In certain circumstances it may be beneficial to mask sensitive data, like passwords, in log messages. Set this to true to mask sensitive data. The default is true.

This setting only works on these classes: AS3Receiver, AS3Sender, Atom, Client(3DS), FTP, FTPServer, IMAP, OFTPClient, SSHClient, SCP, Server(3DS), Sexec, SFTP, SFTPServer, SSHServer, TCPClient, TCPServer.

UseDaemonThreads: Whether threads created by the class are daemon threads.

If set to True (default), when the class creates a thread, the thread's Daemon property will be explicitly set to True. When set to False, the class will not set the Daemon property on the created thread. The default value is True.

UseInternalSecurityAPI: Whether or not to use the system security libraries or an internal implementation.

When set to false, the class will use the system security libraries by default to perform cryptographic functions where applicable.

Setting this configuration setting to true tells the class to use the internal implementation instead of using the system security libraries.

This setting is set to false by default on all platforms.

Trappable Errors (Rc4 Class)

RC4 Errors


	101 Unsupported algorithm.
	102 No Key specified.
	103 No IV specified.
	104 Cannot read or write file.
	107 Block size is not valid for this algorithm.
	108 Key size is not valid for this algorithm.
	111 OutputFile already exists and Overwrite is False.
	121 The specified key is invalid.
	123 IV size is not valid for this algorithm.
	304 Cannot write file.
	305 Cannot read file.
	306 Cannot create file.
	2004 Invalid padding. This may be an indication that the key is incorrect.