org.zkoss.poi.poifs.crypt

Class AgileDecryptor

java.lang.Object

org.zkoss.poi.poifs.crypt.Decryptor

org.zkoss.poi.poifs.crypt.AgileDecryptor

public class AgileDecryptor
extends Decryptor

Author:

Gary King

Field Summary

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

DEFAULT_PASSWORD

Constructor Summary

Constructors

Modifier	Constructor and Description
protected	AgileDecryptor(EncryptionInfo info)

Method Summary

Modifier and Type	Method and Description
protected byte[]	generateIv(int algorithm, byte[] salt, byte[] blockKey)
java.io.InputStream	getDataStream(DirectoryNode dir) Return a stream with decrypted data.
long	getLength() Returns the length of the encytpted data that can be safely read with Decryptor.getDataStream(org.zkoss.poi.poifs.filesystem.DirectoryNode).
boolean	verifyPassword(java.lang.String password)

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

getBlockSize, getDataStream, getDataStream, getInstance, hashPassword

Methods inherited from class java.lang.Object

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

Constructor Detail

AgileDecryptor

protected AgileDecryptor(EncryptionInfo info)

Method Detail

verifyPassword

public boolean verifyPassword(java.lang.String password)
                       throws java.security.GeneralSecurityException

Specified by:

verifyPassword in class Decryptor

Throws:

java.security.GeneralSecurityException

getDataStream

public java.io.InputStream getDataStream(DirectoryNode dir)
                                  throws java.io.IOException,
                                         java.security.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:

java.io.IOException

java.security.GeneralSecurityException

getLength

public long getLength()

Description copied from class: Decryptor

Returns the length of the encytpted data that can be safely read with Decryptor.getDataStream(org.zkoss.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.zkoss.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

generateIv

protected byte[] generateIv(int algorithm,
                            byte[] salt,
                            byte[] blockKey)
                     throws java.security.NoSuchAlgorithmException

Throws:

java.security.NoSuchAlgorithmException