anon.mixminion.message

Class Decoder

java.lang.Object

anon.mixminion.message.Decoder

public class Decoder
extends java.lang.Object

Author:

Stefan Roenisch

Field Summary

Fields

Modifier and Type	Field and Description
private int	KEY_LEN
private java.lang.String	m_message
private java.lang.String	m_password
private int	MAXHOPS
private int	PACKETSIZE
private int	TYPE_FRAGMENTED
private int	TYPE_SINGLETON
private int	TYPE_UNKNOWN

Constructor Summary

Constructors

Constructor and Description
Decoder(java.lang.String message, java.lang.String password) Constructor

Method Summary

Modifier and Type	Method and Description
private int	byteToInt(byte[] b, int offset) Calculates the int value of a given ByteArray
java.lang.String	decode() Method to decode a given payload as String
private int	testPayload(byte[] payload) Tests a given payload for being a plaintext one
private java.lang.String	trytoReassemble(byte[] fragment) try's to reassemble the message the fragment belongs to and returns either null or the reassembled message
private byte[]	unwhiten(byte[] m) Unwhites a ByteArray in the fashion of mixminion

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

KEY_LEN

private final int KEY_LEN

See Also:

Constant Field Values

MAXHOPS

private final int MAXHOPS

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Constant Field Values

PACKETSIZE

private final int PACKETSIZE

TYPE_SINGLETON

private final int TYPE_SINGLETON

See Also:

Constant Field Values

TYPE_FRAGMENTED

private final int TYPE_FRAGMENTED

See Also:

Constant Field Values

TYPE_UNKNOWN

private final int TYPE_UNKNOWN

See Also:

Constant Field Values

m_message

private java.lang.String m_message

m_password

private java.lang.String m_password

Constructor Detail

Decoder

public Decoder(java.lang.String message,
               java.lang.String password)

Constructor

Parameters:

message - The message to be decoded

password - The password needed for the Keyring

Method Detail

decode

public java.lang.String decode()
                        throws java.io.IOException

Method to decode a given payload as String

Returns:

String decodedMessages

Throws:

java.io.IOException

testPayload

private int testPayload(byte[] payload)

Tests a given payload for being a plaintext one

Parameters:

payload -

Returns:

An integer denoting the type of the message. 1 - Singleton Message 2 - Fragmented Message 0 - Unknown message type

trytoReassemble

private java.lang.String trytoReassemble(byte[] fragment)

try's to reassemble the message the fragment belongs to and returns either null or the reassembled message

Parameters:

fragment -

Returns:

byteToInt

private int byteToInt(byte[] b,
                      int offset)

Calculates the int value of a given ByteArray

Parameters:

b -

offset -

Returns:

int value of the bytearray

unwhiten

private byte[] unwhiten(byte[] m)

Unwhites a ByteArray in the fashion of mixminion

Parameters:

m -

Returns: