ccs.crypt
Class AbstractBlockCipherOutputStream

java.lang.Object
  java.io.OutputStream
      java.io.FilterOutputStream
          ccs.crypt.CipherOutputStream
              ccs.crypt.AbstractBlockCipherOutputStream

All Implemented Interfaces:

java.io.Closeable, java.io.Flushable

Direct Known Subclasses:

BCCHOutputStream

public abstract class AbstractBlockCipherOutputStream
extends CipherOutputStream

A Block-cipher output stream. This handles the housekeeping, and delegates all actual crypto to subclasses.

Field Summary

Fields inherited from class ccs.crypt.CipherOutputStream

plainlen, temp8

Fields inherited from class java.io.FilterOutputStream

out

Constructor Summary

protected

AbstractBlockCipherOutputStream(DammedOutputStream os, long plainlen, AbstractBlockCipher cipher)

Method Summary

void	finish() Completes the encryption but does not close the underlying stream.
void	write(byte[] text, int off, int len)
protected abstract void	writeHeader(java.io.OutputStream os) Write the first part of the "header", not including any required stream length information.

Methods inherited from class ccs.crypt.CipherOutputStream

close, flush, write

Methods inherited from class java.io.FilterOutputStream

write

Methods inherited from class java.lang.Object

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

Constructor Detail

AbstractBlockCipherOutputStream

protected AbstractBlockCipherOutputStream(DammedOutputStream os,
                                          long plainlen,
                                          AbstractBlockCipher cipher)

Method Detail

write

public void write(byte[] text,
                  int off,
                  int len)
           throws java.io.IOException

Specified by:

write in class CipherOutputStream

Throws:

java.io.IOException

finish

public void finish()
            throws java.io.IOException

Completes the encryption but does not close the underlying stream.

Specified by:

finish in class CipherOutputStream

Throws:

java.io.IOException - if the finish failed for some reason.

writeHeader

protected abstract void writeHeader(java.io.OutputStream os)
                             throws java.io.IOException

Write the first part of the "header", not including any required stream length information. For CBC ciphers, this is usually just the IV. NB. You should wash the header through your MAC. The CCSBlockCipher's buffer is available as scratch space.

Parameters:

os - The stream to write to.

Throws:

java.io.IOException