Poly1305 Class

Properties   Methods   Events   Config Settings   Errors  

The Poly1305 class may be used to produce a MAC (or Tag) value using the Poly1305 algorithm.

Syntax

ipworksencrypt.Poly1305

Remarks

The Poly1305 class implements the Poly1305 algorithm defined in RFC 7539. This may be used to compute a MAC (or Tag) value on data of any length.

The Key must be set to a 256 bit (32 byte) key before computing the MAC. The computed MAC is 128 bit (32 bytes) in size.

ComputeMAC Notes

ComputeMAC computes the MAC (Message Authentication Code) from the input data.

Before calling this method set Key to a 256 bit (32 byte) key. If EncodeMAC is set to True (default) the output data will be hex encoded.

Input Notes

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

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

• SetInputStream
• InputFile
• InputMessage

When a valid source is found the search stops.

After calling this method MACValue will be populated with the computed 128 bit (16 byte) value.

ComputeMAC Example

Poly1305 poly1305 = new Poly1305(); poly1305.KeyB = new byte[] { 0x1c, 0x92, 0x40, 0xa5, 0xeb, 0x55, 0xd3, 0x8a, 0xf3, 0x33, 0x88, 0x86, 0x04, 0xf6, 0xb5, 0xf0, 0x47, 0x39, 0x17, 0xc1, 0x40, 0x2b, 0x80, 0x09, 0x9d, 0xca, 0x5c, 0xbc, 0x20, 0x70, 0x75, 0xc0 }; poly1305.InputMessage = "Hello Polly"; poly1305.EncodeMAC = true; //hex output poly1305.ComputeMAC(); //This outputs "113019A3ACF5ED2FBB7A45AC1FD67DA1" Console.WriteLine(poly1305.MACValue);

ComputeMACBlock Notes

ComputeMACBlock allows input to the class to be specified in blocks. This method will return the MAC value only when the parameter LastBlock is True.

InputBuffer specifies the input data.

LastBlock specifies whether the block is the last block. If this is False the method will return an empty byte array.

To calculate the MAC value of data that is broken apart into multiple blocks make multiple calls to this method. For instance: //Encode output in hex poly1305.EncodeMAC = true; //hex output //Pass any number of parts, of any size poly1305.ComputeMACBlock(part1,false); poly1305.ComputeMACBlock(part2,false); poly1305.ComputeMACBlock(part3,false); //Pass true for the last block poly1305.ComputeMACBlock(lastPart,true); //The MACValue property holds the MAC value Console.WriteLine(poly1305.MACValue);

Property List

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

EncodeMAC Property (Poly1305 Class)

Whether the MAC value is hex encoded.

Syntax

public boolean isEncodeMAC();


public void setEncodeMAC(boolean encodeMAC);

Default Value

True

Remarks

This property specifies whether the computed MAC value is hex encoded. When set to True (default) the class will hex encoded the computed MAC for easier use. Set this value to False to obtain the MAC value in an unmodified form.

The default value is True.

InputFile Property (Poly1305 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 (Poly1305 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.

Key Property (Poly1305 Class)

The 256 bit (32 byte) key to be used when computing a MAC (Message Authentication Code).

Syntax

public byte[] getKey();


public void setKey(byte[] key);

Default Value

""

Remarks

This property holds the secret key used when computing the MACValue. The key must be 256 bits (32 bytes) long.

MACValue Property (Poly1305 Class)

The computed MAC value.

Syntax

public byte[] getMACValue();

Default Value

""

Remarks

The 128 bit (16 byte) MAC value calculated after calling ComputeMAC.

This property is read-only.

ComputeMAC Method (Poly1305 Class)

Computes the MAC.

Syntax

public void computeMAC();

Remarks

ComputeMAC computes the MAC (Message Authentication Code) from the input data.

Before calling this method set Key to a 256 bit (32 byte) key. If EncodeMAC is set to True (default) the output data will be hex encoded.

Input Notes

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

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

• SetInputStream
• InputFile
• InputMessage

When a valid source is found the search stops.

After calling this method MACValue will be populated with the computed 128 bit (16 byte) value.

ComputeMAC Example

Poly1305 poly1305 = new Poly1305(); poly1305.KeyB = new byte[] { 0x1c, 0x92, 0x40, 0xa5, 0xeb, 0x55, 0xd3, 0x8a, 0xf3, 0x33, 0x88, 0x86, 0x04, 0xf6, 0xb5, 0xf0, 0x47, 0x39, 0x17, 0xc1, 0x40, 0x2b, 0x80, 0x09, 0x9d, 0xca, 0x5c, 0xbc, 0x20, 0x70, 0x75, 0xc0 }; poly1305.InputMessage = "Hello Polly"; poly1305.EncodeMAC = true; //hex output poly1305.ComputeMAC(); //This outputs "113019A3ACF5ED2FBB7A45AC1FD67DA1" Console.WriteLine(poly1305.MACValue);

ComputeMACBlock Method (Poly1305 Class)

Computes the MAC value of specified data.

Syntax

public byte[] computeMACBlock(byte[] inputBuffer, boolean lastBlock);

Remarks

ComputeMACBlock allows input to the class to be specified in blocks. This method will return the MAC value only when the parameter LastBlock is True.

InputBuffer specifies the input data.

LastBlock specifies whether the block is the last block. If this is False the method will return an empty byte array.

To calculate the MAC value of data that is broken apart into multiple blocks make multiple calls to this method. For instance: //Encode output in hex poly1305.EncodeMAC = true; //hex output //Pass any number of parts, of any size poly1305.ComputeMACBlock(part1,false); poly1305.ComputeMACBlock(part2,false); poly1305.ComputeMACBlock(part3,false); //Pass true for the last block poly1305.ComputeMACBlock(lastPart,true); //The MACValue property holds the MAC value Console.WriteLine(poly1305.MACValue);

Config Method (Poly1305 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.

Reset Method (Poly1305 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 (Poly1305 Class)

Sets the stream from which the class will read data.

Syntax

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

Remarks

This method sets the stream from which the class will read data.

Input Notes

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

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

• SetInputStream
• InputFile
• InputMessage

When a valid source is found the search stops.

Error Event (Poly1305 Class)

Fired when information is available about errors during data delivery.

Syntax

public class DefaultPoly1305EventListener implements Poly1305EventListener {
  ...
  public void error(Poly1305ErrorEvent e) {}
  ...
}

public class Poly1305ErrorEvent {
  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 (Poly1305 Class)

Fired as progress is made.

Syntax

public class DefaultPoly1305EventListener implements Poly1305EventListener {
  ...
  public void progress(Poly1305ProgressEvent e) {}
  ...
}

public class Poly1305ProgressEvent {
  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 (Poly1305 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.

Poly1305 Config Settings

Base Config Settings

Trappable Errors (Poly1305 Class)

Poly1305 Errors

	104   Cannot read or write file.
	108   Invalid key size.
	304   Cannot write file.
	305   Cannot read file.