public void Init(
bool forEncryption,
ICipherParameters parameters)
{
if (!(parameters is KeyParameter))
throw new ArgumentException("invalid parameter passed to SKIPJACK init - " + parameters.GetType().ToString());
byte[] keyBytes = ((KeyParameter)parameters).GetKey();
this.encrypting = forEncryption;
this.key0 = new int[32];
this.key1 = new int[32];
this.key2 = new int[32];
this.key3 = new int[32];
//
// expand the key to 128 bytes in 4 parts (saving us a modulo, multiply
// and an addition).
//
for (int i = 0; i < 32; i ++)
{
key0[i] = keyBytes[(i * 4) % 10] & 0xff;
key1[i] = keyBytes[(i * 4 + 1) % 10] & 0xff;
key2[i] = keyBytes[(i * 4 + 2) % 10] & 0xff;
key3[i] = keyBytes[(i * 4 + 3) % 10] & 0xff;
}
}
