bt.protocol.crypto

Class MSECipher

java.lang.Object

bt.protocol.crypto.MSECipher

public class MSECipher
extends Object

RC4-drop1024 stream cipher, used in Message Stream Encryption protocol. Ciphers that are returned by getEncryptionCipher() and getDecryptionCipher() will be different, depending on which of the factory methods was used to build an instance of this class: - connection initiating side should use forInitiator(byte[], TorrentId) factory method - receiver of connection request should use forReceiver(byte[], TorrentId) factory method

Since:

1.2

Method Summary

Modifier and Type	Method and Description
static MSECipher	forInitiator(byte[] S, TorrentId torrentId) Create MSE cipher for connection initiator
static MSECipher	forReceiver(byte[] S, TorrentId torrentId) Create MSE cipher for receiver of the connection request
Cipher	getDecryptionCipher()
Cipher	getEncryptionCipher()
static boolean	isKeySizeSupported(int keySize)

Methods inherited from class java.lang.Object

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

Method Detail

isKeySizeSupported

public static boolean isKeySizeSupported(int keySize)
                                  throws BtException

Throws:

BtException - if the check can't be performed, e.g. when the MSE-specific cipher transformation is not supported in the current JDK.

Since:

1.6

forInitiator

public static MSECipher forInitiator(byte[] S,
                                     TorrentId torrentId)

Create MSE cipher for connection initiator

Parameters:

S - Shared secret

torrentId - Torrent id

Returns:

MSE cipher configured for use by connection initiator

Since:

1.2

forReceiver

public static MSECipher forReceiver(byte[] S,
                                    TorrentId torrentId)

Create MSE cipher for receiver of the connection request

Parameters:

S - Shared secret

torrentId - Torrent id

Returns:

MSE cipher configured for use by receiver of the connection request

Since:

1.2

getEncryptionCipher

public Cipher getEncryptionCipher()

Returns:

Cipher for encrypting outgoing data

Since:

1.2

getDecryptionCipher

public Cipher getDecryptionCipher()

Returns:

Cipher for decrypting incoming data

Since:

1.2