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

protected HMac	mac
protected long	seqNo

Constructor Summary

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

Method Summary

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

Methods inherited from class java.lang.Object

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

Field Detail

seqNo

protected long seqNo

mac

protected HMac mac

Constructor Detail

TlsMac

public 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

public int getSize()

Returns:

The Keysize of the mac.

calculateMac

public 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.