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:

java.lang.Cloneable

public class AgileDecryptor
extends Decryptor
implements java.lang.Cloneable

Decryptor implementation for Agile Encryption

AgileDecryptor

protected AgileDecryptor()

verifyPassword

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

set decryption password

Specified by:

verifyPassword in class Decryptor

Throws:

java.security.GeneralSecurityException

verifyPassword

public boolean verifyPassword(java.security.KeyPair keyPair,
                              java.security.cert.X509Certificate x509)
                       throws java.security.GeneralSecurityException

instead of a password, it's also possible to decrypt via certificate. Warning: this code is experimental and hasn't been validated

Parameters:

keyPair -

x509 -

Returns:

true, when the data can be successfully decrypted with the given private key

Throws:

java.security.GeneralSecurityException

See Also:

Agile encryption with certificates

getNextBlockSize

protected static int getNextBlockSize(int inputLen,
                                      int blockSize)

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 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 javax.crypto.Cipher initCipherForBlock(javax.crypto.Cipher existing,
                                                        int block,
                                                        boolean lastChunk,
                                                        EncryptionInfo encryptionInfo,
                                                        javax.crypto.SecretKey skey,
                                                        int encryptionMode)
                                                 throws java.security.GeneralSecurityException

Throws:

java.security.GeneralSecurityException

clone

public AgileDecryptor clone()
                     throws java.lang.CloneNotSupportedException

Overrides:

clone in class Decryptor

Throws:

java.lang.CloneNotSupportedException