TripleDES Component

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Encrypt and decrypt data with TripleDES, successor to the DES encryption algorithm.

Syntax

TipcTripleDES

Remarks

The TripleDES component is used to encrypt and decrypt data with TripleDES, successor to the DES encryption algorithm.

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

Input and Output Properties

The component 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();

Note that by default the component uses a key size of 192. You may specify the key size (such as 128 or 168) by setting KeySize.

Property List

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

Method List

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

Event List

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

Config Settings

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

CipherMode Property (TripleDES Component)

The cipher mode of operation.

Syntax

property CipherMode: TipcTCipherModes read get_CipherMode write set_CipherMode;

TipcTCipherModes = (
  cmCBC,
  cmECB,
  cmOFB,
  cmCFB,
  cmCTS,
  cm8OFB,
  cm8CFB
);

Default Value

cmCBC

Remarks

The cipher mode of operation.

Possible values are:

InputFile Property (TripleDES Component)

The file to process.

Syntax

property InputFile: String read get_InputFile write set_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 component 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 (TripleDES Component)

The message to process.

Syntax

property InputMessage: String read get_InputMessage write set_InputMessage;
property InputMessageB: TBytes read get_InputMessageB write set_InputMessageB;

Default Value

''

Remarks

This property specifies the message to be processed.

Input and Output Properties

The component 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 (TripleDES Component)

The initialization vector (IV).

Syntax

property IV: String read get_IV write set_IV;
property IVB: TBytes read get_IVB write set_IVB;

Default Value

''

Remarks

This property specifies the initialization vector (IV). By default this property is empty and the component 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 (TripleDES Component)

The secret key for the symmetric algorithm.

Syntax

property Key: String read get_Key write set_Key;
property KeyB: TBytes read get_KeyB write set_KeyB;

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 component as necessary.

Legal Key and Block Sizes (in bits)

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 (TripleDES Component)

A password to generate the Key and IV .

Syntax

property KeyPassword: String read get_KeyPassword write set_KeyPassword;

Default Value

''

Remarks

When this property is set the component 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 (TripleDES Component)

The output file when encrypting or decrypting.

Syntax

property OutputFile: String read get_OutputFile write set_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 component 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 (TripleDES Component)

The output message after processing.

Syntax

property OutputMessage: String read get_OutputMessage;
property OutputMessageB: TBytes read get_OutputMessageB;

Default Value

''

Remarks

This property will be populated with the output from the operation if OutputFile is not set.

Input and Output Properties

The component 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 (TripleDES Component)

Indicates whether or not the component should overwrite files.

Syntax

property Overwrite: Boolean read get_Overwrite write set_Overwrite;

Default Value

false

Remarks

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

PaddingMode Property (TripleDES Component)

The padding mode.

Syntax

property PaddingMode: TipcTPaddingModes read get_PaddingMode write set_PaddingMode;

TipcTPaddingModes = (
  pmPKCS7,
  pmZeros,
  pmNone,
  pmANSIX923,
  pmISO10126
);

Default Value

pmPKCS7

Remarks

PaddingMode is used to pad the final input block to guarantee that it is the correct size required for the selected CipherMode. If the input size is a multiple of the cipher's BlockSize, an extra block of padding will be appended to the input. This enables the decrypting agent to know with certainty how many bytes of padding are included. Each mode pads the data differently. Possible values are:

When calling Decrypt the PaddingMode must match the value used when the data was encrypted.

Note: When using a value of 2 (pmNone), unless the length of input is an exact multiple of the cipher's input BlockSize, the final block of plaintext may be lost.

UseHex Property (TripleDES Component)

Whether input or output is hex encoded.

Syntax

property UseHex: Boolean read get_UseHex write set_UseHex;

Default Value

false

Remarks

This property specifies whether the encrypted data is hex encoded.

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

Config Method (TripleDES Component)

Sets or retrieves a configuration setting.

Syntax

function Config(ConfigurationString: String): String;

Remarks

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

These settings are similar in functionality to properties, but they are rarely used. In order to avoid "polluting" the property namespace of the component, 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 (TripleDES Component)

Decrypts the data.

Syntax

procedure 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 component 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 (TripleDES Component)

Decrypts a block and returns the decrypted data.

Syntax

function DecryptBlock(InputBuffer: TBytes; LastBlock: Boolean): TBytes;

Remarks

This method will decrypt the specified block and return the decrypted data.

InputBuffer specifies the encrypted block to decrypt.

LastBlock indicates whether the block is the last block.

Encrypt Method (TripleDES Component)

Encrypts the data.

Syntax

procedure 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 component 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 (TripleDES Component)

Encrypts data and returns the encrypted block.

Syntax

function EncryptBlock(InputBuffer: TBytes; LastBlock: Boolean): TBytes;

Remarks

This method will encrypt the input data and return the encrypted block.

InputBuffer specifies the input data to encrypt.

LastBlock specifies whether the block is the last block.

Reset Method (TripleDES Component)

Resets the component.

Syntax

procedure Reset();

Remarks

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

SetInputStream Method (TripleDES Component)

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

Syntax

procedure SetInputStream(InputStream: TStream);

Remarks

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

Input and Output Properties

The component 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 (TripleDES Component)

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

Syntax

procedure SetOutputStream(OutputStream: TStream);

Remarks

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

Input and Output Properties

The component 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 (TripleDES Component)

Fired when information is available about errors during data delivery.

Syntax

type TErrorEvent = procedure (
  Sender: TObject;
  ErrorCode: Integer;
  const Description: String
) of Object;

property OnError: TErrorEvent read FOnError write FOnError;

Remarks

The Error event is fired in case of exceptional conditions during message processing. Normally the component raises 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 (TripleDES Component)

Fired as progress is made.

Syntax

type TProgressEvent = procedure (
  Sender: TObject;
  BytesProcessed: Int64;
  PercentProcessed: Integer
) of Object;

property OnProgress: TProgressEvent read FOnProgress write FOnProgress;

Remarks

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

The PercentProcessed parameter indicates the current status of the operation.

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

Config Settings (TripleDES Component)

The component 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 component, access to these internal properties is provided through the Config method.

TripleDES Config Settings

Base Config Settings

Trappable Errors (TripleDES Component)

TripleDES Errors