org.apache.poi.poifs.crypt

Class Decryptor

java.lang.Object

org.apache.poi.poifs.crypt.Decryptor

Direct Known Subclasses:

AgileDecryptor, BinaryRC4Decryptor, CryptoAPIDecryptor, StandardDecryptor

public abstract class Decryptor
extends java.lang.Object

Field Summary

Fields

Modifier and Type	Field and Description
static java.lang.String	DEFAULT_PASSWORD
static java.lang.String	DEFAULT_POIFS_ENTRY

Method Summary

Modifier and Type	Method and Description
abstract java.io.InputStream	getDataStream(DirectoryNode dir) Return a stream with decrypted data.
java.io.InputStream	getDataStream(NPOIFSFileSystem fs)
java.io.InputStream	getDataStream(POIFSFileSystem fs)
static Decryptor	getInstance(EncryptionInfo info)
byte[]	getIntegrityHmacKey()
byte[]	getIntegrityHmacValue()
abstract long	getLength() Returns the length of the encrypted data that can be safely read with getDataStream(org.apache.poi.poifs.filesystem.DirectoryNode).
javax.crypto.SecretKey	getSecretKey()
byte[]	getVerifier()
abstract boolean	verifyPassword(java.lang.String password)

Methods inherited from class java.lang.Object

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

Field Detail

DEFAULT_PASSWORD

public static final java.lang.String DEFAULT_PASSWORD

See Also:

Constant Field Values

DEFAULT_POIFS_ENTRY

public static final java.lang.String DEFAULT_POIFS_ENTRY

See Also:

Constant Field Values

Method Detail

getDataStream

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

Return a stream with decrypted data.

Use 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

Parameters:

dir - the node to read from

Returns:

decrypted stream

Throws:

java.io.IOException

java.security.GeneralSecurityException

verifyPassword

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

Throws:

java.security.GeneralSecurityException

getLength

public abstract long getLength()

Returns the length of the encrypted data that can be safely read with 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 getDataStream(org.apache.poi.poifs.filesystem.DirectoryNode), an attempt to call getLength() prior to getDataStream() will result in IllegalStateException.

Returns:

length of the encrypted data

Throws:

java.lang.IllegalStateException - if getDataStream(org.apache.poi.poifs.filesystem.DirectoryNode) was not called

getInstance

public static Decryptor getInstance(EncryptionInfo info)

getDataStream

public java.io.InputStream getDataStream(NPOIFSFileSystem fs)
                                  throws java.io.IOException,
                                         java.security.GeneralSecurityException

Throws:

java.io.IOException

java.security.GeneralSecurityException

getDataStream

public java.io.InputStream getDataStream(POIFSFileSystem fs)
                                  throws java.io.IOException,
                                         java.security.GeneralSecurityException

Throws:

java.io.IOException

java.security.GeneralSecurityException

getVerifier

public byte[] getVerifier()

getSecretKey

public javax.crypto.SecretKey getSecretKey()

getIntegrityHmacKey

public byte[] getIntegrityHmacKey()

getIntegrityHmacValue

public byte[] getIntegrityHmacValue()