| public decrypt ( byte criptedData, byte destination ) : void | ||
| criptedData | byte | |
| destination | byte | |
| return | void | |
public ArrayList decrypt(byte[] encryptedData, int length)
{
ArrayList response = new ArrayList();
UInt16 pss = 0;
UInt16 cseq = 0;
UInt16 sseq = 0;
PacketReader readerEncrypted = new PacketReader(encryptedData);
readerEncrypted.incrementOffsetByValue(1); // skip 0x01
IV = readerEncrypted.readBytes(16);
tf.setIV(IV);
// Read the whole Data
innerBuffer = new byte[encryptedData.Length - 17];
byte[] decryptBuffer = readerEncrypted.readBytes(encryptedData.Length - 17);
tf.decrypt(decryptBuffer, innerBuffer);
// just copy to clean
byte[] decryptedPacket = innerBuffer;
innerBuffer = new byte[2048];
PacketReader reader = new PacketReader(decryptedPacket);
UInt32 crc32fromPacket = reader.readUInt32(1);
byte[] packetCheckData = reader.readBytes(decryptedPacket.Length - 4);
UInt32 crc32plainDataToCompare = NumericalUtils.ByteArrayToUint32(crc32.checksumB(packetCheckData, 1), 1);
if (crc32plainDataToCompare != crc32fromPacket)
{
Output.WriteLine("Oh oh, CRC didnt matched in this packet");
}
// as we read the whole packet for verifiy we reset the offset to read the other things
reader.setOffsetOverrideValue(4);
UInt16 packetSize = reader.readUInt16(1);
// UInt32 timeStamp = reader.readUInt32(1); // Well we didnt need it - but just read it as uint32
UInt32 seqValues = reader.readUInt32(0);
cseq = (UInt16)(seqValues & 0xFFF);
sseq = (UInt16)(seqValues >> 12 & 0xFFF);
pss = (UInt16)(seqValues >> 24 & 0xFF);
// Finally add our responses and read the rest of the packet
response.Add(reader.readBytes(packetSize - 4));
response.Add(pss);
response.Add(cseq);
response.Add(sseq);
return(response);
}
public byte[] decryptMargin(byte[] packet)
{
ArrayUtils.copy(packet, 1, IV, 0, 16);
int decryptBuffer = packet.Length - 17;
byte[] packetToDecrypt = new byte[decryptBuffer];
ArrayUtils.copy(packet, 17, packetToDecrypt, 0, packet.Length - 17);
tf.setIV(IV);
tf.setKey(TF_Key);
byte[] decryptedBytes = new byte[packetToDecrypt.Length];
tf.decrypt(packetToDecrypt, decryptedBytes);
byte[] decryptedPacket = new byte[decryptedBytes.Length - 10];
ArrayUtils.copy(decryptedBytes, 10, decryptedPacket, 0, decryptedBytes.Length - 10);
return(decryptedPacket);
}
private int twofishDecrypt()
{
byte[] key = { 0x6C, 0xAB, 0x8E, 0xCC, 0xE7, 0x3C, 0x22, 0x47, 0xDB, 0xEB, 0xDE, 0x1A, 0xA8, 0xE7, 0x5F, 0xB8 };
byte[] iv = { 0x30, 0x30, 0x30, 0x30, 0x30, 0x30, 0x30, 0x30, 0x30, 0x30, 0x30, 0x30, 0x30, 0x30, 0x30, 0x30 };
byte[] cipherText = { 0x77, 0x7f, 0x54, 0xc6, 0xc9, 0x9e, 0x35, 0x56, 0x26, 0x4b, 0xc0, 0x17, 0x96, 0x33, 0x79, 0xe8 };
byte[] knownResult = { 0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07, 0x08, 0x09, 0x0a, 0x0b, 0x0c, 0x0d, 0x0e, 0x0f };
byte[] result = new byte[16];
MxoTwofish tf = new MxoTwofish();
tf.setIV(iv);
tf.setKey(key);
tf.decrypt(cipherText, result);
if (!ArrayUtils.equal(knownResult, result))
{
Output.Write("Failed\n");
return(0);
}
Output.Write("OK\n");
return(1);
}
public byte[] decryptMargin(byte[] packet)
{
if (packet.Length < 17)
{
// This happens - but shouldnt happen.
return(null);
}
ArrayUtils.copy(packet, 1, IV, 0, 16);
int decryptBuffer = packet.Length - 17;
byte[] packetToDecrypt = new byte[decryptBuffer];
ArrayUtils.copy(packet, 17, packetToDecrypt, 0, packet.Length - 17);
tf.setIV(IV);
tf.setKey(TF_Key);
byte[] decryptedBytes = new byte[packetToDecrypt.Length];
tf.decrypt(packetToDecrypt, decryptedBytes);
byte[] decryptedPacket;
if (decryptedBytes.Length > 10)
{
decryptedPacket = new byte[decryptedBytes.Length - 10];
}
else
{
decryptedPacket = new byte[decryptedBytes.Length];
}
ArrayUtils.copy(decryptedBytes, 10, decryptedPacket, 0, decryptedBytes.Length - 10);
return(decryptedPacket);
}
private int twofishDecrypt()
{
byte[] key = { 0x6C, 0xAB, 0x8E, 0xCC, 0xE7, 0x3C, 0x22, 0x47, 0xDB, 0xEB, 0xDE, 0x1A, 0xA8, 0xE7, 0x5F, 0xB8 };
byte[] iv = { 0x30, 0x30, 0x30, 0x30, 0x30, 0x30, 0x30, 0x30, 0x30, 0x30, 0x30, 0x30, 0x30, 0x30, 0x30, 0x30 };
byte[] cipherText = {0x77,0x7f,0x54,0xc6,0xc9,0x9e,0x35,0x56,0x26,0x4b,0xc0,0x17,0x96,0x33,0x79,0xe8};
byte[] knownResult = {0x00,0x01,0x02,0x03,0x04,0x05,0x06,0x07, 0x08 ,0x09, 0x0a, 0x0b, 0x0c, 0x0d, 0x0e, 0x0f};
byte[] result = new byte[16];
MxoTwofish tf = new MxoTwofish();
tf.setIV(iv);
tf.setKey(key);
tf.decrypt(cipherText,result);
if (!ArrayUtils.equal(knownResult, result)){
Output.Write("Failed\n");
return 0;
}
Output.Write("OK\n");
return 1;
}
