org.bouncycastle.crypto.tls
Class TlsMac

java.lang.Object
  org.bouncycastle.crypto.tls.TlsMac

public class TlsMac
extends java.lang.Object

A generic TLS MAC implementation, which can be used with any kind of Digest to act as an HMAC.

Field Summary

private HMac	mac
private long	seqNo

Constructor Summary

protected

TlsMac(Digest digest, byte[] key_block, int offset, int len) Generate a new instance of an TlsMac.

Method Summary

protected byte[]	calculateMac(short type, byte[] message, int offset, int len) Calculate the mac for some given data.
protected int	getSize()

Methods inherited from class java.lang.Object

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

Field Detail

seqNo

private long seqNo

mac

private HMac mac

Constructor Detail

TlsMac

protected TlsMac(Digest digest,
                 byte[] key_block,
                 int offset,
                 int len)

Generate a new instance of an TlsMac.

Parameters:

digest - The digest to use.

key_block - A byte-array where the key for this mac is located.

offset - The number of bytes to skip, before the key starts in the buffer.

len - The length of the key.

Method Detail

getSize

protected int getSize()

Returns:

The Keysize of the mac.

calculateMac

protected byte[] calculateMac(short type,
                              byte[] message,
                              int offset,
                              int len)

Calculate the mac for some given data.

TlsMac will keep track of the sequence number internally.

Parameters:

type - The message type of the message.

message - A byte-buffer containing the message.

offset - The number of bytes to skip, before the message starts.

len - The length of the message.

Returns:

A new byte-buffer containing the mac value.