protected byte calculateByte(byte b) {
if (counter > 0 && counter % 1024 == 0) {
BlockCipher base = cfbEngine.getUnderlyingCipher();
base.init(false, key);
byte[] nextKey = new byte[32];
base.processBlock(C, 0, nextKey, 0);
base.processBlock(C, 8, nextKey, 8);
base.processBlock(C, 16, nextKey, 16);
base.processBlock(C, 24, nextKey, 24);
key = new KeyParameter(nextKey);
base.init(true, key);
byte[] iv = cfbEngine.getCurrentIV();
base.processBlock(iv, 0, iv, 0);
cfbEngine.init(forEncryption, new ParametersWithIV(key, iv));
}
counter++;
return cfbEngine.calculateByte(b);
}
public void init(boolean forEncryption, CipherParameters params) throws IllegalArgumentException {
counter = 0;
cfbEngine.init(forEncryption, params);
this.forEncryption = forEncryption;
if (params instanceof ParametersWithIV) {
params = ((ParametersWithIV) params).getParameters();
}
if (params instanceof ParametersWithRandom) {
params = ((ParametersWithRandom) params).getParameters();
}
if (params instanceof ParametersWithSBox) {
params = ((ParametersWithSBox) params).getParameters();
}
key = (KeyParameter) params;
}
public int processBlock(byte[] in, int inOff, byte[] out, int outOff)
throws DataLengthException, IllegalStateException {
this.processBytes(in, inOff, cfbEngine.getBlockSize(), out, outOff);
return cfbEngine.getBlockSize();
}
public int getBlockSize() {
return cfbEngine.getBlockSize();
}
public String getAlgorithmName() {
String name = cfbEngine.getAlgorithmName();
return name.substring(0, name.indexOf('/')) + "/G" + name.substring(name.indexOf('/') + 1);
}
public void reset() {
counter = 0;
cfbEngine.reset();
}
