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:

Closeable, Flushable, AutoCloseable

Direct Known Subclasses:

BinaryRC4Encryptor.BinaryRC4CipherOutputStream, CryptoAPIEncryptor.CryptoAPICipherOutputStream

@Internal
public abstract class ChunkedCipherOutputStream
extends FilterOutputStream

Field Summary

Fields inherited from class java.io.FilterOutputStream

out

Constructor Summary

Constructors

Constructor and Description
ChunkedCipherOutputStream(DirectoryNode dir, int chunkSize)
ChunkedCipherOutputStream(OutputStream stream, int chunkSize)

Method Summary

Modifier and Type	Method and Description
protected abstract void	calculateChecksum(File fileOut, int oleStreamSize)
void	close()
protected abstract void	createEncryptionInfoEntry(DirectoryNode dir, File tmpFile)
protected byte[]	getChunk()
protected int	getChunkMask()
protected BitSet	getPlainByteFlags()
protected long	getPos()
protected long	getTotalPos()
protected abstract Cipher	initCipherForBlock(Cipher existing, int block, boolean lastChunk)
Cipher	initCipherForBlock(int block, boolean lastChunk)
protected int	invokeCipher(int posInChunk, boolean doFinal) Helper function for overriding the cipher invocation, i.e.
void	setNextRecordSize(int recordSize, boolean isPlain) Some ciphers (actually just XOR) are based on the record size, which needs to be set before encryption
void	write(byte[] b)
void	write(byte[] b, int off, int len)
protected void	write(byte[] b, int off, int len, boolean writePlain)
void	write(int b)
protected void	writeChunk(boolean continued)
void	writePlain(byte[] b, int off, int len)

Methods inherited from class java.io.FilterOutputStream

flush

Methods inherited from class java.lang.Object

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

Constructor Detail

ChunkedCipherOutputStream

public ChunkedCipherOutputStream(DirectoryNode dir,
                                 int chunkSize)
                          throws IOException,
                                 GeneralSecurityException

Throws:

IOException

GeneralSecurityException

ChunkedCipherOutputStream

public ChunkedCipherOutputStream(OutputStream stream,
                                 int chunkSize)
                          throws IOException,
                                 GeneralSecurityException

Throws:

IOException

GeneralSecurityException

Method Detail

initCipherForBlock

public final Cipher initCipherForBlock(int block,
                                       boolean lastChunk)
                                throws IOException,
                                       GeneralSecurityException

Throws:

IOException

GeneralSecurityException

initCipherForBlock

protected abstract Cipher initCipherForBlock(Cipher existing,
                                             int block,
                                             boolean lastChunk)
                                      throws IOException,
                                             GeneralSecurityException

Throws:

IOException

GeneralSecurityException

calculateChecksum

protected abstract void calculateChecksum(File fileOut,
                                          int oleStreamSize)
                                   throws GeneralSecurityException,
                                          IOException

Throws:

GeneralSecurityException

IOException

createEncryptionInfoEntry

protected abstract void createEncryptionInfoEntry(DirectoryNode dir,
                                                  File tmpFile)
                                           throws IOException,
                                                  GeneralSecurityException

Throws:

IOException

GeneralSecurityException

write

public void write(int b)
           throws IOException

Overrides:

write in class FilterOutputStream

Throws:

IOException

write

public void write(byte[] b)
           throws IOException

Overrides:

write in class FilterOutputStream

Throws:

IOException

write

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

Overrides:

write in class FilterOutputStream

Throws:

IOException

writePlain

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

Throws:

IOException

write

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

Throws:

IOException

getChunkMask

protected int getChunkMask()

writeChunk

protected void writeChunk(boolean continued)
                   throws IOException

Throws:

IOException

invokeCipher

protected int invokeCipher(int posInChunk,
                           boolean doFinal)
                    throws GeneralSecurityException

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

Throws:

BadPaddingException

IllegalBlockSizeException

ShortBufferException

GeneralSecurityException

close

public void close()
           throws IOException

Specified by:

close in interface Closeable

Specified by:

close in interface AutoCloseable

Overrides:

close in class FilterOutputStream

Throws:

IOException

getChunk

protected byte[] getChunk()

getPlainByteFlags

protected 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