package org.bouncycastle.jcajce.provider.asymmetric.util;
import org.bouncycastle.crypto.BlockCipher;
import org.bouncycastle.crypto.BufferedBlockCipher;
import org.bouncycastle.jce.spec.IESParameterSpec;
public class IESUtil
{
public static IESParameterSpec guessParameterSpec(BufferedBlockCipher iesBlockCipher, byte[] nonce)
{
if (iesBlockCipher == null)
{
return new IESParameterSpec(null, null, 128);
}
else
{
BlockCipher underlyingCipher = iesBlockCipher.getUnderlyingCipher();
if (underlyingCipher.getAlgorithmName().equals("DES") ||
underlyingCipher.getAlgorithmName().equals("RC2") ||
underlyingCipher.getAlgorithmName().equals("RC5-32") ||
underlyingCipher.getAlgorithmName().equals("RC5-64"))
{
return new IESParameterSpec(null, null, 64, 64, nonce);
}
else if (underlyingCipher.getAlgorithmName().equals("SKIPJACK"))
{
return new IESParameterSpec(null, null, 80, 80, nonce);
}
else if (underlyingCipher.getAlgorithmName().equals("GOST28147"))
{
return new IESParameterSpec(null, null, 256, 256, nonce);
}
return new IESParameterSpec(null, null, 128, 128, nonce);
}
}
}