Package org.docx4j.org.apache.poi.poifs.crypt.binaryrc4

Class BinaryRC4Decryptor

java.lang.Object

org.docx4j.org.apache.poi.poifs.crypt.Decryptor

org.docx4j.org.apache.poi.poifs.crypt.binaryrc4.BinaryRC4Decryptor

public class BinaryRC4Decryptor
extends Decryptor

Field Summary

Fields inherited from class org.docx4j.org.apache.poi.poifs.crypt.Decryptor

builder, DEFAULT_PASSWORD, DEFAULT_POIFS_ENTRY

Constructor Summary

Constructors

Modifier	Constructor	Description
protected	BinaryRC4Decryptor(BinaryRC4EncryptionInfoBuilder builder)

Method Summary

Modifier and Type	Method	Description
protected static SecretKey	generateSecretKey(String password, EncryptionVerifier ver)
InputStream	getDataStream(DirectoryNode dir)	Return a stream with decrypted data.
long	getLength()	Returns the length of the encrypted data that can be safely read with Decryptor.getDataStream(org.docx4j.org.apache.poi.poifs.filesystem.DirectoryNode).
protected static Cipher	initCipherForBlock(Cipher cipher, int block, EncryptionInfoBuilder builder, SecretKey skey, int encryptMode)
boolean	verifyPassword(String password)

Methods inherited from class org.docx4j.org.apache.poi.poifs.crypt.Decryptor

getBlockSizeInBytes, getDataStream, getDataStream, getDataStream, getInstance, getIntegrityHmacKey, getIntegrityHmacValue, getKeySizeInBytes, getSecretKey, getVerifier, setIntegrityHmacKey, setIntegrityHmacValue, setSecretKey, setVerifier

Methods inherited from class java.lang.Object

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

Constructor Details

BinaryRC4Decryptor

protected BinaryRC4Decryptor(BinaryRC4EncryptionInfoBuilder builder)

Method Details

verifyPassword

public boolean verifyPassword(String password)

Specified by:

verifyPassword in class Decryptor

initCipherForBlock

protected static Cipher initCipherForBlock(Cipher cipher,
 int block,
 EncryptionInfoBuilder builder,
 SecretKey skey,
 int encryptMode)
                                    throws GeneralSecurityException

Throws:

GeneralSecurityException

generateSecretKey

protected static SecretKey generateSecretKey(String password,
 EncryptionVerifier ver)

getDataStream

public InputStream getDataStream(DirectoryNode dir)
                          throws IOException,
GeneralSecurityException

Description copied from class: Decryptor

Return a stream with decrypted data.

Use Decryptor.getLength() to get the size of that data that can be safely read from the stream. Just reading to the end of the input stream is not sufficient because there are normally padding bytes that must be discarded

Specified by:

getDataStream in class Decryptor

Parameters:

dir - the node to read from

Returns:

decrypted stream

Throws:

IOException

GeneralSecurityException

getLength

public long getLength()

Description copied from class: Decryptor

Returns the length of the encrypted data that can be safely read with Decryptor.getDataStream(org.docx4j.org.apache.poi.poifs.filesystem.DirectoryNode). Just reading to the end of the input stream is not sufficient because there are normally padding bytes that must be discarded

The length variable is initialized in Decryptor.getDataStream(org.docx4j.org.apache.poi.poifs.filesystem.DirectoryNode), an attempt to call getLength() prior to getDataStream() will result in IllegalStateException.

Specified by:

getLength in class Decryptor

Returns:

length of the encrypted data