org.apache.poi.poifs.crypt
Class ChunkedCipherOutputStream

java.lang.Object
  java.io.OutputStream
      java.io.FilterOutputStream
          org.apache.poi.poifs.crypt.ChunkedCipherOutputStream

All Implemented Interfaces:

java.io.Closeable, java.io.Flushable

Direct Known Subclasses:

BinaryRC4Encryptor.BinaryRC4CipherOutputStream, CryptoAPIEncryptor.CryptoAPICipherOutputStream

@Internal
public abstract class ChunkedCipherOutputStream
extends java.io.FilterOutputStream

ChunkedCipherOutputStream

public ChunkedCipherOutputStream(DirectoryNode dir,
                                 int chunkSize)
                          throws java.io.IOException,
                                 java.security.GeneralSecurityException

Throws:

java.io.IOException

java.security.GeneralSecurityException

ChunkedCipherOutputStream

public ChunkedCipherOutputStream(java.io.OutputStream stream,
                                 int chunkSize)
                          throws java.io.IOException,
                                 java.security.GeneralSecurityException

Throws:

java.io.IOException

java.security.GeneralSecurityException

initCipherForBlock

public final javax.crypto.Cipher initCipherForBlock(int block,
                                                    boolean lastChunk)
                                             throws java.io.IOException,
                                                    java.security.GeneralSecurityException

Throws:

java.io.IOException

java.security.GeneralSecurityException

initCipherForBlock

protected abstract javax.crypto.Cipher initCipherForBlock(javax.crypto.Cipher existing,
                                                          int block,
                                                          boolean lastChunk)
                                                   throws java.io.IOException,
                                                          java.security.GeneralSecurityException

Throws:

java.io.IOException

java.security.GeneralSecurityException

calculateChecksum

protected abstract void calculateChecksum(java.io.File fileOut,
                                          int oleStreamSize)
                                   throws java.security.GeneralSecurityException,
                                          java.io.IOException

Throws:

java.security.GeneralSecurityException

java.io.IOException

createEncryptionInfoEntry

protected abstract void createEncryptionInfoEntry(DirectoryNode dir,
                                                  java.io.File tmpFile)
                                           throws java.io.IOException,
                                                  java.security.GeneralSecurityException

Throws:

java.io.IOException

java.security.GeneralSecurityException

write

public void write(int b)
           throws java.io.IOException

Overrides:

write in class java.io.FilterOutputStream

Throws:

java.io.IOException

write

public void write(byte[] b)
           throws java.io.IOException

Overrides:

write in class java.io.FilterOutputStream

Throws:

java.io.IOException

write

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

Overrides:

write in class java.io.FilterOutputStream

Throws:

java.io.IOException

writePlain

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

Throws:

java.io.IOException

write

protected void write(byte[] b,
                     int off,
                     int len,
                     boolean writePlain)
              throws java.io.IOException

Throws:

java.io.IOException

getChunkMask

protected int getChunkMask()

writeChunk

protected void writeChunk(boolean continued)
                   throws java.io.IOException

Throws:

java.io.IOException

invokeCipher

protected int invokeCipher(int posInChunk,
                           boolean doFinal)
                    throws java.security.GeneralSecurityException

Helper function for overriding the cipher invocation, i.e. XOR doesn't use a cipher and uses it's own implementation

Throws:

javax.crypto.BadPaddingException

javax.crypto.IllegalBlockSizeException

javax.crypto.ShortBufferException

java.security.GeneralSecurityException

close

public void close()
           throws java.io.IOException

Specified by:

close in interface java.io.Closeable

Overrides:

close in class java.io.FilterOutputStream

Throws:

java.io.IOException

getChunk

protected byte[] getChunk()

getPlainByteFlags

protected java.util.BitSet getPlainByteFlags()

getPos

protected long getPos()

getTotalPos

protected long getTotalPos()

setNextRecordSize

public void setNextRecordSize(int recordSize,
                              boolean isPlain)

Some ciphers (actually just XOR) are based on the record size, which needs to be set before encryption

Parameters:

recordSize - the size of the next record

isPlain - true if the record is unencrypted