org.bouncycastle.openpgp
Class PGPPadding

java.lang.Object
  |
  +--org.bouncycastle.openpgp.PGPPadding

public class PGPPadding

extends java.lang.Object

The PGPPadding contains random data, and can be used to defend against traffic analysis on version 2 SEIPD messages and Transferable Public Keys.

Such a padding packet MUST be ignored when received.

Field Summary

static int	MAX_PADDING_LEN Maximum random padding length.
static int	MIN_PADDING_LEN Minimum random padding length in octets.

Constructor Summary

PGPPadding()
Generate a new, random PGPPadding object.

PGPPadding(BCPGInputStream in)
Default constructor.

PGPPadding(int len)
Generate a new, random PGPPadding object.

PGPPadding(int len, java.security.SecureRandom random)
Generate a new, random PGPPadding object.

PGPPadding(java.security.SecureRandom random)
Generate a new, random PGPPadding object.

Method Summary

void	encode(java.io.OutputStream outStream)
byte[]	getEncoded()
byte[]	getEncoded(PacketFormat format)
byte[]	getPadding() Return the padding octets as a byte array.

Methods inherited from class java.lang.Object

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

Field Detail

MIN_PADDING_LEN

public static final int MIN_PADDING_LEN

Minimum random padding length in octets. Chosen totally arbitrarily.

MAX_PADDING_LEN

public static final int MAX_PADDING_LEN

Maximum random padding length. Chosen somewhat arbitrarily, as SSH also uses max 255 bytes for random padding.

See Also:

rfc4253 - Binary Packet Protocol

Constructor Detail

PGPPadding

public PGPPadding(BCPGInputStream in)
           throws java.io.IOException

Default constructor.

Parameters:

in - packet input stream

Throws:

java.io.IOException -

PGPPadding

public PGPPadding()

Generate a new, random PGPPadding object. The padding consists of n random bytes, where n is a number between (inclusive) MIN_PADDING_LEN and MAX_PADDING_LEN.

PGPPadding

public PGPPadding(java.security.SecureRandom random)

Generate a new, random PGPPadding object. The padding consists of n random bytes, where n is a number between (inclusive) MIN_PADDING_LEN and MAX_PADDING_LEN.

Parameters:

random - random number generator instance

PGPPadding

public PGPPadding(int len)

Generate a new, random PGPPadding object. The padding consists of len random bytes.

PGPPadding

public PGPPadding(int len,
                  java.security.SecureRandom random)

Generate a new, random PGPPadding object. The padding consists of len random bytes.

Parameters:

len - number of random octets

random - random number generator instance

Method Detail

getPadding

public byte[] getPadding()

Return the padding octets as a byte array.

Returns:

padding octets

encode

public void encode(java.io.OutputStream outStream)
            throws java.io.IOException

getEncoded

public byte[] getEncoded()
                  throws java.io.IOException

getEncoded

public byte[] getEncoded(PacketFormat format)
                  throws java.io.IOException