# ChaCha Component

The ChaCha component can be used to encrypt and decrypt data with the ChaCha20 algorithm.

## Syntax

```text
nsoftware.IPWorksEncrypt.ChaCha
```

## Remarks

The component implements ChaCha20 as defined in RFC 7539. This may be used to both encrypt and decrypt data. The component also support Authenticated Encryption with Additional Data (AEAD) via AEAD_CHACHA20_POLY1305. To enable the use of AEAD set [UseAEAD](#useaead-property-chacha-component) to True.

Data may be encrypted and decrypted in its entirety by calling [Encrypt](#encrypt-method-chacha-component) and [Decrypt](#decrypt-method-chacha-component) or chunk by chunk by calling [EncryptBlock](#encryptblock-method-chacha-component) and [DecryptBlock](#decryptblock-method-chacha-component).

In all operations a [Key](#key-property-chacha-component) and [IV](#iv-property-chacha-component) must be used. If [IV](#iv-property-chacha-component) is not set one is automatically generated. [KeyPassword](#keypassword-property-chacha-component) may be set in order to automatically generate both a [Key](#key-property-chacha-component) and [IV](#iv-property-chacha-component) when a method is called. The same [KeyPassword](#keypassword-property-chacha-component), or [Key](#key-property-chacha-component) and [IV](#iv-property-chacha-component) pair are used on both sides of the operation data can be encrypted and decrypted.

## Encrypt Notes

[Encrypt](#encrypt-method-chacha-component) will encrypt the specified data. The following properties are applicable:

- [IV](#iv-property-chacha-component) (required)
- [Key](#key-property-chacha-component) (required)
- [UseAEAD](#useaead-property-chacha-component) (optional)
- [AdditionalAuthData](#additionalauthdata-property-chacha-component) (optional - applicable if [UseAEAD](#useaead-property-chacha-component) is True);

**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](#setinputstream-method-chacha-component)
- [InputFile](#inputfile-property-chacha-component)
- [InputMessage](#inputmessage-property-chacha-component)

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

- [SetOutputStream](#setoutputstream-method-chacha-component)
- [OutputFile](#outputfile-property-chacha-component)
- [OutputMessage](#outputmessage-property-chacha-component): The output data is written to this property if no other destination is specified.

When using streams, you may need to additionally set [CloseInputStreamAfterProcessing](#CloseInputStreamAfterProcessing) or [CloseOutputStreamAfterProcessing](#CloseOutputStreamAfterProcessing).

**Additional Notes**

The [Key](#key-property-chacha-component) property must be set to a 256 bit (32 byte) value. This is the only allowed value for ChaCha20. If [KeyPassword](#keypassword-property-chacha-component) is set both [Key](#key-property-chacha-component) and [IV](#iv-property-chacha-component) will be automatically generated when [Encrypt](#encrypt-method-chacha-component) is called.

The [IV](#iv-property-chacha-component) should typically be set to a 96 bit (12 byte) value. See the [IV](#iv-property-chacha-component) property for details on using a 64 bit (8 byte) value. If [IV](#iv-property-chacha-component) is not set a 96 bit (12 byte) value will automatically be generated by the component when [Encrypt](#encrypt-method-chacha-component) is called.

[InitialCounter](#InitialCounter) may be set for specific cases where an initial counter of 1 is needed. The default value is 0 and is recommended.

During encryption the [Progress](#progress-event-chacha-component) event will fire as data is encrypted.

**Encrypt Example**

```csharp
Chacha chacha = new Chacha();
chacha.KeyB = new byte[]{ 0xBB, 0x76, 0x17, 0xC9, 0x05, 0x73, 0x4A, 0x8D, 0x59, 0x9D, 0x7B, 0x0D, 0x86, 0x2A, 0x03, 0x82, 0x50, 0x6A, 0x70, 0xFB, 0xA8, 0x56, 0x47, 0x1B, 0x1E, 0x68, 0x0B, 0x2B, 0x34, 0x18, 0x0F, 0xE2 };
chacha.IVB = new byte[] { 0x0D, 0xE4, 0x43, 0x40, 0x29, 0xAD, 0x70, 0x7D, 0x7B, 0x32, 0xB5, 0xC7 };
chacha.InputMessage = "hello chacha!";
chacha.Encrypt();

//chacha.OutputMessageB contains the byte[] of the encrypted data. The above code produces the following encrypted bytes.
// {0x35, 0xBA, 0x31, 0x60, 0x02, 0x77, 0x57, 0x06, 0x5F, 0x6E, 0xE0, 0xD4, 0x76}
```

**AEAD Notes**

When encrypting and [UseAEAD](#useaead-property-chacha-component) is True [AdditionalAuthData](#additionalauthdata-property-chacha-component) optionally holds data that is authenticated but not encrypted.

After encrypting the message the [AuthTag](#authtag-property-chacha-component) property will be populated. To include the [AuthTag](#authtag-property-chacha-component) in the output set [IncludeAuthTag](#IncludeAuthTag) to True.

**Encrypt with AEAD Example**

```csharp
Chacha chacha = new Chacha();
chacha.KeyB = new byte[] { 0xBB, 0x76, 0x17, 0xC9, 0x05, 0x73, 0x4A, 0x8D, 0x59, 0x9D, 0x7B, 0x0D, 0x86, 0x2A, 0x03, 0x82, 0x50, 0x6A, 0x70, 0xFB, 0xA8, 0x56, 0x47, 0x1B, 0x1E, 0x68, 0x0B, 0x2B, 0x34, 0x18, 0x0F, 0xE2 };
chacha.IVB = new byte[] { 0x0D, 0xE4, 0x43, 0x40, 0x29, 0xAD, 0x70, 0x7D, 0x7B, 0x32, 0xB5, 0xC7 };

chacha.UseAEAD = true;
chacha.AdditionalAuthData = "my auth data.";
chacha.InputMessage = "hello chacha!";
chacha.Encrypt();

//chacha.OutputMessageB contains the byte[] of the encrypted data. The above code produces the following encrypted bytes:
// {0x67, 0xF5, 0xC7, 0xE4, 0xE6, 0xD6, 0xC2, 0xF4, 0x09, 0xE3, 0x90, 0xF2, 0x65}

//chacha.AuthTagB contains the byte[] of the AuthTag. The above code produces the following authentication tag:
// {0x46, 0x35, 0xFD, 0x33, 0x30, 0x52, 0xAA, 0x6B, 0xBA, 0x32, 0x16, 0xA6, 0x48, 0x12, 0x52, 0x78}
```

## Encrypt Block Notes

[EncryptBlock](#encryptblock-method-chacha-component) will encrypt the input data and return the encrypted block. The encrypted block will always be the same length as the decrypted data. The following properties are applicable:

- [IV](#iv-property-chacha-component) (required)
- [Key](#key-property-chacha-component) (required)

*InputBuffer* specifies the input data to encrypt.

*LastBlock* specifies whether the block is the last block. Required when [UseAEAD](#useaead-property-chacha-component) is True. When *LastBlock* is True the component will calculate the [AuthTag](#authtag-property-chacha-component) value. If [UseAEAD](#useaead-property-chacha-component) is False the value of *LastBlock* is not used.

**EncryptBlock Example**

```csharp
Chacha chacha = new Chacha();
chacha.KeyB = new byte[] { 0xBB, 0x76, 0x17, 0xC9, 0x05, 0x73, 0x4A, 0x8D, 0x59, 0x9D, 0x7B, 0x0D, 0x86, 0x2A, 0x03, 0x82, 0x50, 0x6A, 0x70, 0xFB, 0xA8, 0x56, 0x47, 0x1B, 0x1E, 0x68, 0x0B, 0x2B, 0x34, 0x18, 0x0F, 0xE2 };
chacha.IVB = new byte[] { 0x0D, 0xE4, 0x43, 0x40, 0x29, 0xAD, 0x70, 0x7D, 0x7B, 0x32, 0xB5, 0xC7 };
chacha.UseAEAD = true;

byte[] tempEncryptedBlock;

//Encrypt any number of blocks of any size
tempEncryptedBlock = chacha.EncryptBlock(part1, false);
tempEncryptedBlock = chacha.EncryptBlock(part2, false);

//Pass true for the last block
tempEncryptedBlock = chacha.EncryptBlock(part3, true);

//Save AuthTag for use when decrypting
byte[] authTag = chacha.AuthTagB;
```

## Decrypt Notes

[Decrypt](#decrypt-method-chacha-component) will decrypt the specified data. The following properties are applicable:

- [IV](#iv-property-chacha-component) (required)
- [Key](#key-property-chacha-component) (required)
- [UseAEAD](#useaead-property-chacha-component) (optional)
- [AuthTag](#authtag-property-chacha-component) (conditional - required if [UseAEAD](#useaead-property-chacha-component) is True)
- [AdditionalAuthData](#additionalauthdata-property-chacha-component) (optional - applicable if [UseAEAD](#useaead-property-chacha-component) is True);

**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](#setinputstream-method-chacha-component)
- [InputFile](#inputfile-property-chacha-component)
- [InputMessage](#inputmessage-property-chacha-component)

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

- [SetOutputStream](#setoutputstream-method-chacha-component)
- [OutputFile](#outputfile-property-chacha-component)
- [OutputMessage](#outputmessage-property-chacha-component): The output data is written to this property if no other destination is specified.

When using streams, you may need to additionally set [CloseInputStreamAfterProcessing](#CloseInputStreamAfterProcessing) or [CloseOutputStreamAfterProcessing](#CloseOutputStreamAfterProcessing).

**Additional Notes**

The [Key](#key-property-chacha-component) property must be set to the 256 bit (32 byte) value originally used to encrypt the data. [IV](#iv-property-chacha-component) must be set to the original IV value used to encrypt the data.

If using a password, [KeyPassword](#keypassword-property-chacha-component) must be set to the same [KeyPassword](#keypassword-property-chacha-component) used when encrypting the data. This will automatically generate both [Key](#key-property-chacha-component) and [IV](#iv-property-chacha-component) when [Decrypt](#decrypt-method-chacha-component) is called.

[InitialCounter](#InitialCounter) may be set for specific cases where an initial counter of 1 is needed. The default value is 0 and is recommended.

During decryption the [Progress](#progress-event-chacha-component) event will fire as data is decrypted.

**Decrypt Example**

```csharp
Chacha chacha = new Chacha();
chacha.KeyB = new byte[] { 0xBB, 0x76, 0x17, 0xC9, 0x05, 0x73, 0x4A, 0x8D, 0x59, 0x9D, 0x7B, 0x0D, 0x86, 0x2A, 0x03, 0x82, 0x50, 0x6A, 0x70, 0xFB, 0xA8, 0x56, 0x47, 0x1B, 0x1E, 0x68, 0x0B, 0x2B, 0x34, 0x18, 0x0F, 0xE2 };
chacha.IVB = new byte[] { 0x0D, 0xE4, 0x43, 0x40, 0x29, 0xAD, 0x70, 0x7D, 0x7B, 0x32, 0xB5, 0xC7 };
chacha.InputMessageB = new byte[] { 0x35, 0xBA, 0x31, 0x60, 0x02, 0x77, 0x57, 0x06, 0x5F, 0x6E, 0xE0, 0xD4, 0x76 };
chacha.Decrypt();

Console.WriteLine(chacha.OutputMessage); //outputs "hello chacha!"
```

**AEAD Notes**

When decrypting [AdditionalAuthData](#additionalauthdata-property-chacha-component) must be set to the same value that was specified when encrypting. [AuthTag](#authtag-property-chacha-component) must be set to the [AuthTag](#authtag-property-chacha-component) value produced when encrypting.

Note: [IncludeAuthTag](#IncludeAuthTag) may be set to True if the [AuthTag](#authtag-property-chacha-component) value was included in the encrypted message.

**Decrypt with AEAD Example**

```csharp
Chacha chacha = new Chacha();
chacha.KeyB = new byte[] { 0xBB, 0x76, 0x17, 0xC9, 0x05, 0x73, 0x4A, 0x8D, 0x59, 0x9D, 0x7B, 0x0D, 0x86, 0x2A, 0x03, 0x82, 0x50, 0x6A, 0x70, 0xFB, 0xA8, 0x56, 0x47, 0x1B, 0x1E, 0x68, 0x0B, 0x2B, 0x34, 0x18, 0x0F, 0xE2 };
chacha.IVB = new byte[] { 0x0D, 0xE4, 0x43, 0x40, 0x29, 0xAD, 0x70, 0x7D, 0x7B, 0x32, 0xB5, 0xC7 };
chacha.AuthTagB = new byte[] { 0x46, 0x35, 0xFD, 0x33, 0x30, 0x52, 0xAA, 0x6B, 0xBA, 0x32, 0x16, 0xA6, 0x48, 0x12, 0x52, 0x78 };
chacha.InputMessageB = new byte[] { 0x67, 0xF5, 0xC7, 0xE4, 0xE6, 0xD6, 0xC2, 0xF4, 0x09, 0xE3, 0x90, 0xF2, 0x65 };

chacha.UseAEAD = true;
chacha.AdditionalAuthData = "my auth data.";
chacha.Decrypt();

Console.WriteLine(chacha.OutputMessage); //outputs "hello chacha!"
```

## Decrypt Block Notes

[DecryptBlock](#decryptblock-method-chacha-component) will decrypt the input data and return the decrypted block. The decrypted block will always be the same length as the encrypted data. The following properties are applicable:

- [IV](#iv-property-chacha-component) (required)
- [Key](#key-property-chacha-component) (required)

*InputBuffer* specifies the input data to decrypt.

*LastBlock* specifies whether the block is the last block. Required when [UseAEAD](#useaead-property-chacha-component) is True. When *LastBlock* is True the component will validate the [AuthTag](#authtag-property-chacha-component) value. If [UseAEAD](#useaead-property-chacha-component) is False the value of *LastBlock* is not used.

**DecryptBlock Example**

```csharp
Chacha chacha = new Chacha();
chacha.KeyB = new byte[] { 0xBB, 0x76, 0x17, 0xC9, 0x05, 0x73, 0x4A, 0x8D, 0x59, 0x9D, 0x7B, 0x0D, 0x86, 0x2A, 0x03, 0x82, 0x50, 0x6A, 0x70, 0xFB, 0xA8, 0x56, 0x47, 0x1B, 0x1E, 0x68, 0x0B, 0x2B, 0x34, 0x18, 0x0F, 0xE2 };
chacha.IVB = new byte[] { 0x0D, 0xE4, 0x43, 0x40, 0x29, 0xAD, 0x70, 0x7D, 0x7B, 0x32, 0xB5, 0xC7 };
chacha.UseAEAD = true;
chacha.AuthTagB = authTag; //Value calculated during encryption.

byte[] tempDecryptedBlock;

//Decrypt any number of blocks of any size
tempDecryptedBlock = chacha.DecryptBlock(part1, false);
tempDecryptedBlock = chacha.DecryptBlock(part2, false);

//Pass true for the last block
tempDecryptedBlock = chacha.DecryptBlock(part3, true);
```

## Property List

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

|  |  |
| --- | --- |
| [AdditionalAuthData](#additionalauthdata-property-chacha-component) | Additional Authentication Data (AAD) used when UseAEAD is True. |
| [AuthTag](#authtag-property-chacha-component) | The authentication tag used when UseAEAD is set to True. |
| [InputFile](#inputfile-property-chacha-component) | The file to process. |
| [InputMessage](#inputmessage-property-chacha-component) | The message to process. |
| [IV](#iv-property-chacha-component) | The initialization vector (IV). |
| [Key](#key-property-chacha-component) | The secret key for the symmetric algorithm. |
| [KeyPassword](#keypassword-property-chacha-component) | A password to generate the [Key](#key-property-chacha-component) and [IV](#iv-property-chacha-component) . |
| [OutputFile](#outputfile-property-chacha-component) | The output file when encrypting or decrypting. |
| [OutputMessage](#outputmessage-property-chacha-component) | The output message after processing. |
| [Overwrite](#overwrite-property-chacha-component) | Indicates whether or not the component should overwrite files. |
| [UseAEAD](#useaead-property-chacha-component) | Whether to use AEAD (Authenticated Encryption with Additional Data). |
| [UseHex](#usehex-property-chacha-component) | Whether input or output is hex encoded. |

## Method List

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

|  |  |
| --- | --- |
| [Config](#config-method-chacha-component) | Sets or retrieves a configuration setting. |
| [Decrypt](#decrypt-method-chacha-component) | Decrypts the data. |
| [DecryptBlock](#decryptblock-method-chacha-component) | Decrypts a block and returns the decrypted data. |
| [Encrypt](#encrypt-method-chacha-component) | Encrypts the data. |
| [EncryptBlock](#encryptblock-method-chacha-component) | Encrypts data and returns the encrypted block. |
| [Reset](#reset-method-chacha-component) | Resets the component. |
| [SetInputStream](#setinputstream-method-chacha-component) | Sets the stream from which the component will read data to encrypt or decrypt. |
| [SetOutputStream](#setoutputstream-method-chacha-component) | Sets the stream to which the component will write encrypted or decrypted data. |

## Event List

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

|  |  |
| --- | --- |
| [Error](#error-event-chacha-component) | Fired when information is available about errors during data delivery. |
| [Progress](#progress-event-chacha-component) | Fired as progress is made. |

## Config Settings

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

|  |  |
| --- | --- |
| [ChaCha20Algorithm](#ChaCha20Algorithm) | Specifies the ChaCha implementation to use. |
| [CloseInputStreamAfterProcessing](#CloseInputStreamAfterProcessing) | Determines whether or not the input stream is closed after processing. |
| [CloseOutputStreamAfterProcessing](#CloseOutputStreamAfterProcessing) | Determines whether or not the output stream is closed after processing. |
| [EncryptedDataEncoding](#EncryptedDataEncoding) | The encoding of the encrypted input or output data. |
| [IncludeAuthTag](#IncludeAuthTag) | Whether to append the authentication tag to the cipher text when UseAEAD is True. |
| [IncludeIV](#IncludeIV) | Whether to prepend the IV to the output data and read the IV from the input data. |
| [InitialCounter](#InitialCounter) | The initial counter value. |
| [IVLength](#IVLength) | The IV length in bytes. |
| [KeyPasswordAlgorithm](#KeyPasswordAlgorithm) | The hash algorithm used to derive the Key and IV from the KeyPassword property. |
| [KeyPasswordIterations](#KeyPasswordIterations) | The number of iterations performed when using KeyPassword to derive the Key and IV. |
| [KeyPasswordSalt](#KeyPasswordSalt) | The salt value used in conjunction with the KeyPassword to derive the Key and IV. |
| [BuildInfo](#BuildInfo) | Information about the product's build. |
| [GUIAvailable](#GUIAvailable) | Whether or not a message loop is available for processing events. |
| [LicenseInfo](#LicenseInfo) | Information about the current license. |
| [MaskSensitiveData](#MaskSensitiveData) | Whether sensitive data is masked in log messages. |
| [UseFIPSCompliantAPI](#UseFIPSCompliantAPI) | Tells the component whether or not to use FIPS certified APIs. |
| [UseInternalSecurityAPI](#UseInternalSecurityAPI) | Whether or not to use the system security libraries or an internal implementation. |

# AdditionalAuthData Property ([ChaCha](#chacha-component) Component)

Additional Authentication Data (AAD) used when UseAEAD is True.

## Syntax

```text
public string AdditionalAuthData { get; set; }
public byte[] AdditionalAuthDataB { get; set; }
```

## Default Value

""

## Remarks

This property specifies data that is authentication but not encrypted. This is only applicable when [UseAEAD](#useaead-property-chacha-component) is True.

Note that AAD data is authenticated but not encrypted, so it is not included in the output.

# AuthTag Property ([ChaCha](#chacha-component) Component)

The authentication tag used when UseAEAD is set to True.

## Syntax

```text
public string AuthTag { get; set; }
public byte[] AuthTagB { get; set; }
```

## Default Value

""

## Remarks

This property holds the 128 bit authentication tag used when [UseAEAD](#useaead-property-chacha-component) is set to True. It is only applicable when [UseAEAD](#useaead-property-chacha-component) is True.

This is populated after calling [Encrypt](#encrypt-method-chacha-component). To also include the value in the output set [IncludeAuthTag](#IncludeAuthTag) to True.

This must be set before calling [Decrypt](#decrypt-method-chacha-component). If the auth tag is included in the encrypted data set [IncludeAuthTag](#IncludeAuthTag) to True before calling [Decrypt](#decrypt-method-chacha-component).

# InputFile Property ([ChaCha](#chacha-component) Component)

The file to process.

## Syntax

```text
public string InputFile { get; set; }
```

## 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](#setinputstream-method-chacha-component)
- InputFile
- [InputMessage](#inputmessage-property-chacha-component)

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

- [SetOutputStream](#setoutputstream-method-chacha-component)
- [OutputFile](#outputfile-property-chacha-component)
- [OutputMessage](#outputmessage-property-chacha-component): The output data is written to this property if no other destination is specified.

When using streams, you may need to additionally set [CloseInputStreamAfterProcessing](#CloseInputStreamAfterProcessing) or [CloseOutputStreamAfterProcessing](#CloseOutputStreamAfterProcessing).

# InputMessage Property ([ChaCha](#chacha-component) Component)

The message to process.

## Syntax

```text
public string InputMessage { get; set; }
public byte[] InputMessageB { get; set; }
```

## 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](#setinputstream-method-chacha-component)
- [InputFile](#inputfile-property-chacha-component)
- InputMessage

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

- [SetOutputStream](#setoutputstream-method-chacha-component)
- [OutputFile](#outputfile-property-chacha-component)
- [OutputMessage](#outputmessage-property-chacha-component): The output data is written to this property if no other destination is specified.

When using streams, you may need to additionally set [CloseInputStreamAfterProcessing](#CloseInputStreamAfterProcessing) or [CloseOutputStreamAfterProcessing](#CloseOutputStreamAfterProcessing).

# IV Property ([ChaCha](#chacha-component) Component)

The initialization vector (IV).

## Syntax

```text
public string IV { get; set; }
public byte[] IVB { get; set; }
```

## Default Value

""

## Remarks

This property specifies the initialization vector (IV). This is also referred to as the nonce. By default this property is empty and the component will automatically generate a new IV value if [KeyPassword](#keypassword-property-chacha-component) or [Key](#key-property-chacha-component) is set before [Encrypt](#encrypt-method-chacha-component) or [EncryptBlock](#encryptblock-method-chacha-component) is called.

The size of the IV may be either 96 bits in length (12 bytes) or 64 bits in length (8 bytes).

**Compatibility Notes**

A 96 bit length value is used for implementations implementing RFC 7539. A 64 bit length value may be used by implementations that follow the original draft of ChaCha. When using a 96 bit length value the maximum file size of data is 256 GB.

If another entity is performing the decryption and it is not known whether it supports 64 bit length values, choose a 96 bit length value by default. This follows the RFC and should be the most widely implemented value.

The component supports both lengths.

Note: If [Key](#key-property-chacha-component) is specified but IV is not, an IV will be automatically generated. To control the length of the IV that is generated set [IVLength](#IVLength).

# Key Property ([ChaCha](#chacha-component) Component)

The secret key for the symmetric algorithm.

## Syntax

```text
public string Key { get; set; }
public byte[] KeyB { get; set; }
```

## 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. This key must be 256 bits in length (32 bytes).

If this property is left empty and [KeyPassword](#keypassword-property-chacha-component) is specified, a Key value will be generated by the component as necessary.

# KeyPassword Property ([ChaCha](#chacha-component) Component)

A password to generate the [Key](#key-property-chacha-component) and [IV](#iv-property-chacha-component) .

## Syntax

```text
public string KeyPassword { get; set; }
```

## Default Value

""

## Remarks

When this property is set the component will calculate values for [Key](#key-property-chacha-component) and [IV](#iv-property-chacha-component) using the PKCS5 password digest algorithm. This provides a simpler alternative to creating and managing [Key](#key-property-chacha-component) and [IV](#iv-property-chacha-component) values directly.

# OutputFile Property ([ChaCha](#chacha-component) Component)

The output file when encrypting or decrypting.

## Syntax

```text
public string OutputFile { get; set; }
```

## Default Value

""

## Remarks

This property specifies the file to which the output will be written when [Encrypt](#encrypt-method-chacha-component) or [Decrypt](#decrypt-method-chacha-component) is called. This may be set to an absolute or relative path.

This property is only applicable to [Encrypt](#encrypt-method-chacha-component) and [Decrypt](#decrypt-method-chacha-component).

**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](#setinputstream-method-chacha-component)
- [InputFile](#inputfile-property-chacha-component)
- [InputMessage](#inputmessage-property-chacha-component)

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

- [SetOutputStream](#setoutputstream-method-chacha-component)
- OutputFile
- [OutputMessage](#outputmessage-property-chacha-component): The output data is written to this property if no other destination is specified.

When using streams, you may need to additionally set [CloseInputStreamAfterProcessing](#CloseInputStreamAfterProcessing) or [CloseOutputStreamAfterProcessing](#CloseOutputStreamAfterProcessing).

# OutputMessage Property ([ChaCha](#chacha-component) Component)

The output message after processing.

## Syntax

```text
public string OutputMessage { get; }
public byte[] OutputMessageB { get; }
```

## Default Value

""

## Remarks

This property will be populated with the output from the operation if [OutputFile](#outputfile-property-chacha-component) and [SetOutputStream](#setoutputstream-method-chacha-component) are 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](#setinputstream-method-chacha-component)
- [InputFile](#inputfile-property-chacha-component)
- [InputMessage](#inputmessage-property-chacha-component)

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

- [SetOutputStream](#setoutputstream-method-chacha-component)
- [OutputFile](#outputfile-property-chacha-component)
- 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](#CloseInputStreamAfterProcessing) or [CloseOutputStreamAfterProcessing](#CloseOutputStreamAfterProcessing).

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

# Overwrite Property ([ChaCha](#chacha-component) Component)

Indicates whether or not the component should overwrite files.

## Syntax

```text
public bool Overwrite { get; set; }
```

## Default Value

False

## Remarks

This property indicates whether or not the component will overwrite [OutputFile](#outputfile-property-chacha-component). If Overwrite is False, an error will be thrown whenever [OutputFile](#outputfile-property-chacha-component) exists before an operation. The default value is False.

# UseAEAD Property ([ChaCha](#chacha-component) Component)

Whether to use AEAD (Authenticated Encryption with Additional Data).

## Syntax

```text
public bool UseAEAD { get; set; }
```

## Default Value

False

## Remarks

If this property is set to True the component uses the algorithm AEAD_CHACHA20_POLY1305 as defined in RFC 7539 to construct a message using AEAD. See [Encrypt](#encrypt-method-chacha-component) and [Decrypt](#decrypt-method-chacha-component) for details.

# UseHex Property ([ChaCha](#chacha-component) Component)

Whether input or output is hex encoded.

## Syntax

```text
public bool UseHex { get; set; }
```

## Default Value

False

## Remarks

This property specifies whether the encrypted data is hex encoded.

If set to True, when [Encrypt](#encrypt-method-chacha-component) is called the component will perform the encryption as normal and then hex encode the output. [OutputMessage](#outputmessage-property-chacha-component) or [OutputFile](#outputfile-property-chacha-component) will hold hex encoded data.

If set to True, when [Decrypt](#decrypt-method-chacha-component) is called the component will expect [InputMessage](#inputmessage-property-chacha-component) or [InputFile](#inputfile-property-chacha-component) to hold hex encoded data. The component will then hex decode the data and perform decryption as normal.

**AEAD Notes**

When [UseAEAD](#useaead-property-chacha-component) is set to True this property also applies to [AuthTag](#authtag-property-chacha-component). After calling [Encrypt](#encrypt-method-chacha-component) [AuthTag](#authtag-property-chacha-component) will hold a hex encoded value. Before calling [Decrypt](#decrypt-method-chacha-component) [AuthTag](#authtag-property-chacha-component) must be set to a hex encoded value.

# Config Method ([ChaCha](#chacha-component) Component)

Sets or retrieves a configuration setting.

## Syntax

```text
public string Config(string configurationString);

Async Version
public async Task<string> Config(string configurationString);
public async Task<string> Config(string configurationString, CancellationToken cancellationToken);
```

## Remarks

Config is a generic method available in every component. It is used to set and retrieve [configuration settings](#config-settings-chacha-component) 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](#config-settings-chacha-component), you must call *Config("PROPERTY")*. The value will be returned as a string.

# Decrypt Method ([ChaCha](#chacha-component) Component)

Decrypts the data.

## Syntax

```text
public void Decrypt();

Async Version
public async Task Decrypt();
public async Task Decrypt(CancellationToken cancellationToken);
```

## Remarks

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

- [IV](#iv-property-chacha-component) (required)
- [Key](#key-property-chacha-component) (required)
- [UseAEAD](#useaead-property-chacha-component) (optional)
- [AuthTag](#authtag-property-chacha-component) (conditional - required if [UseAEAD](#useaead-property-chacha-component) is True)
- [AdditionalAuthData](#additionalauthdata-property-chacha-component) (optional - applicable if [UseAEAD](#useaead-property-chacha-component) is True);

**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](#setinputstream-method-chacha-component)
- [InputFile](#inputfile-property-chacha-component)
- [InputMessage](#inputmessage-property-chacha-component)

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

- [SetOutputStream](#setoutputstream-method-chacha-component)
- [OutputFile](#outputfile-property-chacha-component)
- [OutputMessage](#outputmessage-property-chacha-component): The output data is written to this property if no other destination is specified.

When using streams, you may need to additionally set [CloseInputStreamAfterProcessing](#CloseInputStreamAfterProcessing) or [CloseOutputStreamAfterProcessing](#CloseOutputStreamAfterProcessing).

**Additional Notes**

The [Key](#key-property-chacha-component) property must be set to the 256 bit (32 byte) value originally used to encrypt the data. [IV](#iv-property-chacha-component) must be set to the original IV value used to encrypt the data.

If using a password, [KeyPassword](#keypassword-property-chacha-component) must be set to the same [KeyPassword](#keypassword-property-chacha-component) used when encrypting the data. This will automatically generate both [Key](#key-property-chacha-component) and [IV](#iv-property-chacha-component) when Decrypt is called.

[InitialCounter](#InitialCounter) may be set for specific cases where an initial counter of 1 is needed. The default value is 0 and is recommended.

During decryption the [Progress](#progress-event-chacha-component) event will fire as data is decrypted.

**Decrypt Example**

```csharp
Chacha chacha = new Chacha();
chacha.KeyB = new byte[] { 0xBB, 0x76, 0x17, 0xC9, 0x05, 0x73, 0x4A, 0x8D, 0x59, 0x9D, 0x7B, 0x0D, 0x86, 0x2A, 0x03, 0x82, 0x50, 0x6A, 0x70, 0xFB, 0xA8, 0x56, 0x47, 0x1B, 0x1E, 0x68, 0x0B, 0x2B, 0x34, 0x18, 0x0F, 0xE2 };
chacha.IVB = new byte[] { 0x0D, 0xE4, 0x43, 0x40, 0x29, 0xAD, 0x70, 0x7D, 0x7B, 0x32, 0xB5, 0xC7 };
chacha.InputMessageB = new byte[] { 0x35, 0xBA, 0x31, 0x60, 0x02, 0x77, 0x57, 0x06, 0x5F, 0x6E, 0xE0, 0xD4, 0x76 };
chacha.Decrypt();

Console.WriteLine(chacha.OutputMessage); //outputs "hello chacha!"
```

**AEAD Notes**

When decrypting [AdditionalAuthData](#additionalauthdata-property-chacha-component) must be set to the same value that was specified when encrypting. [AuthTag](#authtag-property-chacha-component) must be set to the [AuthTag](#authtag-property-chacha-component) value produced when encrypting.

Note: [IncludeAuthTag](#IncludeAuthTag) may be set to True if the [AuthTag](#authtag-property-chacha-component) value was included in the encrypted message.

**Decrypt with AEAD Example**

```csharp
Chacha chacha = new Chacha();
chacha.KeyB = new byte[] { 0xBB, 0x76, 0x17, 0xC9, 0x05, 0x73, 0x4A, 0x8D, 0x59, 0x9D, 0x7B, 0x0D, 0x86, 0x2A, 0x03, 0x82, 0x50, 0x6A, 0x70, 0xFB, 0xA8, 0x56, 0x47, 0x1B, 0x1E, 0x68, 0x0B, 0x2B, 0x34, 0x18, 0x0F, 0xE2 };
chacha.IVB = new byte[] { 0x0D, 0xE4, 0x43, 0x40, 0x29, 0xAD, 0x70, 0x7D, 0x7B, 0x32, 0xB5, 0xC7 };
chacha.AuthTagB = new byte[] { 0x46, 0x35, 0xFD, 0x33, 0x30, 0x52, 0xAA, 0x6B, 0xBA, 0x32, 0x16, 0xA6, 0x48, 0x12, 0x52, 0x78 };
chacha.InputMessageB = new byte[] { 0x67, 0xF5, 0xC7, 0xE4, 0xE6, 0xD6, 0xC2, 0xF4, 0x09, 0xE3, 0x90, 0xF2, 0x65 };

chacha.UseAEAD = true;
chacha.AdditionalAuthData = "my auth data.";
chacha.Decrypt();

Console.WriteLine(chacha.OutputMessage); //outputs "hello chacha!"
```

# DecryptBlock Method ([ChaCha](#chacha-component) Component)

Decrypts a block and returns the decrypted data.

## Syntax

```text
public byte[] DecryptBlock(byte[] inputBuffer, bool lastBlock);

Async Version
public async Task<byte[]> DecryptBlock(byte[] inputBuffer, bool lastBlock);
public async Task<byte[]> DecryptBlock(byte[] inputBuffer, bool lastBlock, CancellationToken cancellationToken);
```

## Remarks

DecryptBlock will decrypt the input data and return the decrypted block. The decrypted block will always be the same length as the encrypted data. The following properties are applicable:

- [IV](#iv-property-chacha-component) (required)
- [Key](#key-property-chacha-component) (required)

*InputBuffer* specifies the input data to decrypt.

*LastBlock* specifies whether the block is the last block. Required when [UseAEAD](#useaead-property-chacha-component) is True. When *LastBlock* is True the component will validate the [AuthTag](#authtag-property-chacha-component) value. If [UseAEAD](#useaead-property-chacha-component) is False the value of *LastBlock* is not used.

**DecryptBlock Example**

```csharp
Chacha chacha = new Chacha();
chacha.KeyB = new byte[] { 0xBB, 0x76, 0x17, 0xC9, 0x05, 0x73, 0x4A, 0x8D, 0x59, 0x9D, 0x7B, 0x0D, 0x86, 0x2A, 0x03, 0x82, 0x50, 0x6A, 0x70, 0xFB, 0xA8, 0x56, 0x47, 0x1B, 0x1E, 0x68, 0x0B, 0x2B, 0x34, 0x18, 0x0F, 0xE2 };
chacha.IVB = new byte[] { 0x0D, 0xE4, 0x43, 0x40, 0x29, 0xAD, 0x70, 0x7D, 0x7B, 0x32, 0xB5, 0xC7 };
chacha.UseAEAD = true;
chacha.AuthTagB = authTag; //Value calculated during encryption.

byte[] tempDecryptedBlock;

//Decrypt any number of blocks of any size
tempDecryptedBlock = chacha.DecryptBlock(part1, false);
tempDecryptedBlock = chacha.DecryptBlock(part2, false);

//Pass true for the last block
tempDecryptedBlock = chacha.DecryptBlock(part3, true);
```

# Encrypt Method ([ChaCha](#chacha-component) Component)

Encrypts the data.

## Syntax

```text
public void Encrypt();

Async Version
public async Task Encrypt();
public async Task Encrypt(CancellationToken cancellationToken);
```

## Remarks

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

- [IV](#iv-property-chacha-component) (required)
- [Key](#key-property-chacha-component) (required)
- [UseAEAD](#useaead-property-chacha-component) (optional)
- [AdditionalAuthData](#additionalauthdata-property-chacha-component) (optional - applicable if [UseAEAD](#useaead-property-chacha-component) is True);

**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](#setinputstream-method-chacha-component)
- [InputFile](#inputfile-property-chacha-component)
- [InputMessage](#inputmessage-property-chacha-component)

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

- [SetOutputStream](#setoutputstream-method-chacha-component)
- [OutputFile](#outputfile-property-chacha-component)
- [OutputMessage](#outputmessage-property-chacha-component): The output data is written to this property if no other destination is specified.

When using streams, you may need to additionally set [CloseInputStreamAfterProcessing](#CloseInputStreamAfterProcessing) or [CloseOutputStreamAfterProcessing](#CloseOutputStreamAfterProcessing).

**Additional Notes**

The [Key](#key-property-chacha-component) property must be set to a 256 bit (32 byte) value. This is the only allowed value for ChaCha20. If [KeyPassword](#keypassword-property-chacha-component) is set both [Key](#key-property-chacha-component) and [IV](#iv-property-chacha-component) will be automatically generated when Encrypt is called.

The [IV](#iv-property-chacha-component) should typically be set to a 96 bit (12 byte) value. See the [IV](#iv-property-chacha-component) property for details on using a 64 bit (8 byte) value. If [IV](#iv-property-chacha-component) is not set a 96 bit (12 byte) value will automatically be generated by the component when Encrypt is called.

[InitialCounter](#InitialCounter) may be set for specific cases where an initial counter of 1 is needed. The default value is 0 and is recommended.

During encryption the [Progress](#progress-event-chacha-component) event will fire as data is encrypted.

**Encrypt Example**

```csharp
Chacha chacha = new Chacha();
chacha.KeyB = new byte[]{ 0xBB, 0x76, 0x17, 0xC9, 0x05, 0x73, 0x4A, 0x8D, 0x59, 0x9D, 0x7B, 0x0D, 0x86, 0x2A, 0x03, 0x82, 0x50, 0x6A, 0x70, 0xFB, 0xA8, 0x56, 0x47, 0x1B, 0x1E, 0x68, 0x0B, 0x2B, 0x34, 0x18, 0x0F, 0xE2 };
chacha.IVB = new byte[] { 0x0D, 0xE4, 0x43, 0x40, 0x29, 0xAD, 0x70, 0x7D, 0x7B, 0x32, 0xB5, 0xC7 };
chacha.InputMessage = "hello chacha!";
chacha.Encrypt();

//chacha.OutputMessageB contains the byte[] of the encrypted data. The above code produces the following encrypted bytes.
// {0x35, 0xBA, 0x31, 0x60, 0x02, 0x77, 0x57, 0x06, 0x5F, 0x6E, 0xE0, 0xD4, 0x76}
```

**AEAD Notes**

When encrypting and [UseAEAD](#useaead-property-chacha-component) is True [AdditionalAuthData](#additionalauthdata-property-chacha-component) optionally holds data that is authenticated but not encrypted.

After encrypting the message the [AuthTag](#authtag-property-chacha-component) property will be populated. To include the [AuthTag](#authtag-property-chacha-component) in the output set [IncludeAuthTag](#IncludeAuthTag) to True.

**Encrypt with AEAD Example**

```csharp
Chacha chacha = new Chacha();
chacha.KeyB = new byte[] { 0xBB, 0x76, 0x17, 0xC9, 0x05, 0x73, 0x4A, 0x8D, 0x59, 0x9D, 0x7B, 0x0D, 0x86, 0x2A, 0x03, 0x82, 0x50, 0x6A, 0x70, 0xFB, 0xA8, 0x56, 0x47, 0x1B, 0x1E, 0x68, 0x0B, 0x2B, 0x34, 0x18, 0x0F, 0xE2 };
chacha.IVB = new byte[] { 0x0D, 0xE4, 0x43, 0x40, 0x29, 0xAD, 0x70, 0x7D, 0x7B, 0x32, 0xB5, 0xC7 };

chacha.UseAEAD = true;
chacha.AdditionalAuthData = "my auth data.";
chacha.InputMessage = "hello chacha!";
chacha.Encrypt();

//chacha.OutputMessageB contains the byte[] of the encrypted data. The above code produces the following encrypted bytes:
// {0x67, 0xF5, 0xC7, 0xE4, 0xE6, 0xD6, 0xC2, 0xF4, 0x09, 0xE3, 0x90, 0xF2, 0x65}

//chacha.AuthTagB contains the byte[] of the AuthTag. The above code produces the following authentication tag:
// {0x46, 0x35, 0xFD, 0x33, 0x30, 0x52, 0xAA, 0x6B, 0xBA, 0x32, 0x16, 0xA6, 0x48, 0x12, 0x52, 0x78}
```

# EncryptBlock Method ([ChaCha](#chacha-component) Component)

Encrypts data and returns the encrypted block.

## Syntax

```text
public byte[] EncryptBlock(byte[] inputBuffer, bool lastBlock);

Async Version
public async Task<byte[]> EncryptBlock(byte[] inputBuffer, bool lastBlock);
public async Task<byte[]> EncryptBlock(byte[] inputBuffer, bool lastBlock, CancellationToken cancellationToken);
```

## Remarks

EncryptBlock will encrypt the input data and return the encrypted block. The encrypted block will always be the same length as the decrypted data. The following properties are applicable:

- [IV](#iv-property-chacha-component) (required)
- [Key](#key-property-chacha-component) (required)

*InputBuffer* specifies the input data to encrypt.

*LastBlock* specifies whether the block is the last block. Required when [UseAEAD](#useaead-property-chacha-component) is True. When *LastBlock* is True the component will calculate the [AuthTag](#authtag-property-chacha-component) value. If [UseAEAD](#useaead-property-chacha-component) is False the value of *LastBlock* is not used.

**EncryptBlock Example**

```csharp
Chacha chacha = new Chacha();
chacha.KeyB = new byte[] { 0xBB, 0x76, 0x17, 0xC9, 0x05, 0x73, 0x4A, 0x8D, 0x59, 0x9D, 0x7B, 0x0D, 0x86, 0x2A, 0x03, 0x82, 0x50, 0x6A, 0x70, 0xFB, 0xA8, 0x56, 0x47, 0x1B, 0x1E, 0x68, 0x0B, 0x2B, 0x34, 0x18, 0x0F, 0xE2 };
chacha.IVB = new byte[] { 0x0D, 0xE4, 0x43, 0x40, 0x29, 0xAD, 0x70, 0x7D, 0x7B, 0x32, 0xB5, 0xC7 };
chacha.UseAEAD = true;

byte[] tempEncryptedBlock;

//Encrypt any number of blocks of any size
tempEncryptedBlock = chacha.EncryptBlock(part1, false);
tempEncryptedBlock = chacha.EncryptBlock(part2, false);

//Pass true for the last block
tempEncryptedBlock = chacha.EncryptBlock(part3, true);

//Save AuthTag for use when decrypting
byte[] authTag = chacha.AuthTagB;
```

# Reset Method ([ChaCha](#chacha-component) Component)

Resets the component.

## Syntax

```text
public void Reset();

Async Version
public async Task Reset();
public async Task Reset(CancellationToken cancellationToken);
```

## Remarks

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

# SetInputStream Method ([ChaCha](#chacha-component) Component)

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

## Syntax

```text
public void SetInputStream(System.IO.Stream inputStream);

Async Version
public async Task SetInputStream(System.IO.Stream inputStream);
public async Task SetInputStream(System.IO.Stream inputStream, CancellationToken cancellationToken);
```

## 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](#inputfile-property-chacha-component)
- [InputMessage](#inputmessage-property-chacha-component)

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

- [SetOutputStream](#setoutputstream-method-chacha-component)
- [OutputFile](#outputfile-property-chacha-component)
- [OutputMessage](#outputmessage-property-chacha-component): The output data is written to this property if no other destination is specified.

When using streams, you may need to additionally set [CloseInputStreamAfterProcessing](#CloseInputStreamAfterProcessing) or [CloseOutputStreamAfterProcessing](#CloseOutputStreamAfterProcessing).

# SetOutputStream Method ([ChaCha](#chacha-component) Component)

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

## Syntax

```text
public void SetOutputStream(System.IO.Stream outputStream);

Async Version
public async Task SetOutputStream(System.IO.Stream outputStream);
public async Task SetOutputStream(System.IO.Stream outputStream, CancellationToken cancellationToken);
```

## 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](#setinputstream-method-chacha-component)
- [InputFile](#inputfile-property-chacha-component)
- [InputMessage](#inputmessage-property-chacha-component)

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

- SetOutputStream
- [OutputFile](#outputfile-property-chacha-component)
- [OutputMessage](#outputmessage-property-chacha-component): The output data is written to this property if no other destination is specified.

When using streams, you may need to additionally set [CloseInputStreamAfterProcessing](#CloseInputStreamAfterProcessing) or [CloseOutputStreamAfterProcessing](#CloseOutputStreamAfterProcessing).

# Error Event ([ChaCha](#chacha-component) Component)

Fired when information is available about errors during data delivery.

## Syntax

```text
public event OnErrorHandler OnError;

public delegate void OnErrorHandler(object sender, ChaChaErrorEventArgs e);

public class ChaChaErrorEventArgs : EventArgs {
  public int ErrorCode { get; }
  public string Description { get; }
}
```

## Remarks

The Error event is fired in case of exceptional conditions during message processing. Normally the component 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](#trappable-errors-chacha-component) section.

# Progress Event ([ChaCha](#chacha-component) Component)

Fired as progress is made.

## Syntax

```text
public event OnProgressHandler OnProgress;

public delegate void OnProgressHandler(object sender, ChaChaProgressEventArgs e);

public class ChaChaProgressEventArgs : EventArgs {
  public long BytesProcessed { get; }
  public int PercentProcessed { get; }
}
```

## 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 ([ChaCha](#chacha-component) 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](#config-method-chacha-component) method.

### ChaCha Config Settings

**ChaCha20Algorithm**: Specifies the ChaCha implementation to use.This setting specifies the ChaCha implementation to use. Possible values are:

- 0 (ChaCha20 - default)
- 1 (XChaCha20)

The XChaCha20 implementation is generally considered to be more secure.

**CloseInputStreamAfterProcessing**: Determines whether or not the input stream is closed after processing.Determines whether or not the input stream set by [SetInputStream](#setinputstream-method-chacha-component) 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](#setoutputstream-method-chacha-component) is closed after processing is complete. The default value is True.

**EncryptedDataEncoding**: The encoding of the encrypted input or output data.This configuration setting specifies how the encrypted data is encoded (if at all).

When [Encrypt](#encrypt-method-chacha-component) is called the component will perform the encryption as normal and then encode the output as specified here. [OutputMessage](#outputmessage-property-chacha-component) or [OutputFile](#outputfile-property-chacha-component) will hold the encoded data.

When [Decrypt](#decrypt-method-chacha-component) is called the component will expect [InputMessage](#inputmessage-property-chacha-component) or [InputFile](#inputfile-property-chacha-component) to hold the encoded data as specified here. The component will then decode the data and perform decryption as normal.

Possible values are:

- 0 (none - default)
- 1 (Base64)
- 2 (Hex)
- 3 (Base64URL)

**IncludeAuthTag**: Whether to append the authentication tag to the cipher text when UseAEAD is True.This setting controls whether [AuthTag](#AuthTag) is appended to the cipher text. This may be useful in cases where the other party knows to look for the authentication tag at the end of the data. The default value is False.

Note: This setting cannot be used in conjunction with [DecryptBlock](#decryptblock-method-chacha-component). When calling [DecryptBlock](#decryptblock-method-chacha-component) [AuthTag](#authtag-property-chacha-component) must be set explicitly and the cipher text being decrypted must not include the auth tag.

**IncludeIV**: Whether to prepend the IV to the output data and read the IV from the input data.If this config is true, the IV will be automatically prepended to the output data when calling [Encrypt](#encrypt-method-chacha-component). When calling [Decrypt](#decrypt-method-chacha-component) and this setting is True, the IV is automatically extracted form the ciphertext. The default value is False.

**InitialCounter**: The initial counter value. This setting specifies the initial counter value. In most cases this is 0 (default), but some protocols may use a value of 1. The default value is *0*.

**IVLength**: The IV length in bytes.This setting specifies the IV length. In most cases this is 12 bytes (default), but some protocols may use a value of 8 bytes. The default value is *12*.

Note: When decrypting, if [IncludeIV](#IncludeIV) is set to True and the IV length was NOT 12 bytes when originally encrypting the data, this setting must be set to the appropriate value before calling [Decrypt](#decrypt-method-chacha-component) or [DecryptBlock](#decryptblock-method-chacha-component).

**KeyPasswordAlgorithm**: The hash algorithm used to derive the Key and IV from the KeyPassword property.This configuration setting specifies which hash algorithm will be used when deriving the [Key](#key-property-chacha-component) and [IV](#iv-property-chacha-component) from [KeyPassword](#keypassword-property-chacha-component). The default value is "MD5". Possible values are:

- "SHA1"
- "MD2"
- "MD5" (default)
- "HMAC-SHA1"
- "HMAC-SHA224"
- "HMAC-SHA256"
- "HMAC-SHA384"
- "HMAC-SHA512"
- "HMAC-MD5"
- "HMAC-RIPEMD160"

When using any HMAC algorithm the PBKDF#2 method from RFC 2898 is used. Any other algorithm uses PBKDF#1 from the same RFC.

**KeyPasswordIterations**: The number of iterations performed when using KeyPassword to derive the Key and IV.This configuration setting specifies the number of iterations performed when using [KeyPassword](#keypassword-property-chacha-component) to calculate values for [Key](#key-property-chacha-component) and [IV](#iv-property-chacha-component). When using PBKDF#2 the default number of iterations is 10,000. When using PBKDF#1 the default number is 10.

**KeyPasswordSalt**: The salt value used in conjunction with the KeyPassword to derive the Key and IV.This configuration setting specifies the hex encoded salt value to be used along with the [KeyPassword](#keypassword-property-chacha-component) when calculating values for [Key](#key-property-chacha-component) and [IV](#iv-property-chacha-component).

### 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 component 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](#GUIAvailable) to *false* will ensure that the component 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 component 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.

**MaskSensitiveData**: 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*.

**UseFIPSCompliantAPI**: Tells the component whether or not to use FIPS certified APIs.When set to *true*, the component will utilize the underlying operating system's certified APIs. Java editions, regardless of OS, utilize Bouncy Castle Federal Information Processing Standards (FIPS), while all other Windows editions make use of Microsoft security libraries.

FIPS mode can be enabled by setting the *UseFIPSCompliantAPI* configuration setting to *true*. This is a static setting that applies to all instances of all components of the toolkit within the process. It is recommended to enable or disable this setting once before the component has been used to establish a connection. Enabling FIPS while an instance of the component is active and connected may result in unexpected behavior.

For more details, please see the [FIPS 140-2 Compliance](https://www.nsoftware.com/kb/articles/fips.rst) article.

NOTE: This setting is applicable only on Windows.

NOTE: Enabling FIPS compliance requires a special license; please contact [sales@nsoftware.com](mailto:sales@nsoftware.com) for details.

**UseInternalSecurityAPI**: Whether or not to use the system security libraries or an internal implementation. When set to *false*, the component will use the system security libraries by default to perform cryptographic functions where applicable. In this case, calls to unmanaged code will be made. In certain environments, this is not desirable. To use a completely managed security implementation, set this setting to *true*.

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

 On Windows, this setting is set to *false* by default. On Linux/macOS, this setting is set to *true* by default.

NOTE: This setting is static. The value set is applicable to all components used in the application.

When this value is set, the product's system dynamic link library (DLL) is no longer required as a reference, as all unmanaged code is stored in that file.

# Trappable Errors ([ChaCha](#chacha-component) Component)

### ChaCha 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. |