Package org.apache.poi.poifs.crypt.agile

Class AgileDecryptor

java.lang.Object

org.apache.poi.poifs.crypt.Decryptor

org.apache.poi.poifs.crypt.agile.AgileDecryptor

All Implemented Interfaces:

GenericRecord

public class AgileDecryptor
extends Decryptor

Decryptor implementation for Agile Encryption

Field Summary

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

DEFAULT_PASSWORD, DEFAULT_POIFS_ENTRY, encryptionInfo

Constructor Summary

Constructors

Modifier	Constructor	Description
protected	AgileDecryptor()
protected	AgileDecryptor(AgileDecryptor other)

Method Summary

Modifier and Type	Method	Description
AgileDecryptor	copy()
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.apache.poi.poifs.filesystem.DirectoryNode).
protected static int	getNextBlockSize(int inputLen, int blockSize)
protected static Cipher	initCipherForBlock(Cipher existing, int block, boolean lastChunk, EncryptionInfo encryptionInfo, SecretKey skey, int encryptionMode)
boolean	verifyPassword(String password)	set decryption password

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

getBlockSizeInBytes, getDataStream, getDataStream, getEncryptionInfo, getGenericProperties, getInstance, getIntegrityHmacKey, getIntegrityHmacValue, getKeySizeInBytes, getSecretKey, getVerifier, initCipherForBlock, setChunkSize, setEncryptionInfo, setIntegrityHmacKey, setIntegrityHmacValue, setSecretKey, setVerifier

Methods inherited from class java.lang.Object

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

Methods inherited from interface org.apache.poi.common.usermodel.GenericRecord

getGenericChildren, getGenericRecordType

Constructor Detail

AgileDecryptor

protected AgileDecryptor()

AgileDecryptor

protected AgileDecryptor(AgileDecryptor other)

Method Detail

verifyPassword

public boolean verifyPassword(String password)
                       throws GeneralSecurityException

set decryption password

Specified by:

verifyPassword in class Decryptor

Throws:

GeneralSecurityException

getNextBlockSize

protected static int getNextBlockSize(int inputLen,
                                      int blockSize)

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.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.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

initCipherForBlock

protected static Cipher initCipherForBlock(Cipher existing,
                                           int block,
                                           boolean lastChunk,
                                           EncryptionInfo encryptionInfo,
                                           SecretKey skey,
                                           int encryptionMode)
                                    throws GeneralSecurityException

Throws:

GeneralSecurityException

copy

public AgileDecryptor copy()

Specified by:

copy in class Decryptor