org.xwiki.crypto.passwd
Interface PasswordCiphertext

All Superinterfaces:

java.io.Serializable

All Known Implementing Classes:

AbstractPasswordCiphertext, AESPasswordCiphertext, CAST5PasswordCiphertext

public interface PasswordCiphertext
extends java.io.Serializable

Ciphertext represents a single password encrypted data. It can be serialized and deserialized and the same password will be able to decrypt it.

Since:

2.5M1

Version:

$Id$

Method Summary

byte[]	decrypt(java.lang.String password) Get the message (i.e.
int	getRequiredKeySize() Get the length of the key which should be output by the keyFunction which is to be passed to init(byte[], String, KeyDerivationFunction).
void	init(byte[] message, java.lang.String password, KeyDerivationFunction initializedKeyFunction) Initialize this ciphertext with a given message (i.e.
byte[]	serialize() Serialize this ciphertext into a byte array which can later be deserialized and the text decrypted from that.

Method Detail

init

void init(byte[] message,
          java.lang.String password,
          KeyDerivationFunction initializedKeyFunction)
          throws java.security.GeneralSecurityException

Initialize this ciphertext with a given message (i.e. plaintext), password, and an initialized key derivation function. To get the data back, use decrypt(String) with the same password.

Parameters:

message - the message which will be encrypted.

password - the password used to encrypt the message.

initializedKeyFunction - an initialized KeyDerivationFunction which will return a key of the length given by getRequiredKeySize().

Throws:

java.security.GeneralSecurityException - if something goes wrong while encrypting.

decrypt

byte[] decrypt(java.lang.String password)
               throws java.security.GeneralSecurityException

Get the message (i.e. plaintext) back from this ciphertext. Most of the time the response is null if the password is incorrect, 1 out of 250 times the output is unintelligable garbage which sneaks undetected past the padding scheme.

Parameters:

password - the user supplied password.

Returns:

the original message or null if the password was wrong.

Throws:

java.security.GeneralSecurityException - if something goes wrong while decrypting.

serialize

byte[] serialize()
                 throws java.io.IOException

Serialize this ciphertext into a byte array which can later be deserialized and the text decrypted from that.

Returns:

a byte array representing this object.

Throws:

java.io.IOException - if something goes wrong in the serialization framework.

getRequiredKeySize

int getRequiredKeySize()

Get the length of the key which should be output by the keyFunction which is to be passed to init(byte[], String, KeyDerivationFunction). Users are expected to call this method and pass the result when initializing the key derivation function then pass the initialized key derivation function to init(byte[], String, KeyDerivationFunction).

Returns:

the length required for the derived key.

See Also:

getRequiredKeySize()