org.bouncycastle.crypto.params.X448PrivateKeyParameters Maven / Gradle / Ivy
package org.bouncycastle.crypto.params;
import java.io.EOFException;
import java.io.IOException;
import java.io.InputStream;
import java.security.SecureRandom;
import org.bouncycastle.math.ec.rfc7748.X448;
import org.bouncycastle.util.Arrays;
import org.bouncycastle.util.io.Streams;
public final class X448PrivateKeyParameters
extends AsymmetricKeyParameter
{
public static final int KEY_SIZE = X448.SCALAR_SIZE;
public static final int SECRET_SIZE = X448.POINT_SIZE;
private final byte[] data = new byte[KEY_SIZE];
public X448PrivateKeyParameters(SecureRandom random)
{
super(true);
X448.generatePrivateKey(random, data);
}
public X448PrivateKeyParameters(byte[] buf)
{
this(validate(buf), 0);
}
public X448PrivateKeyParameters(byte[] buf, int off)
{
super(true);
System.arraycopy(buf, off, data, 0, KEY_SIZE);
}
public X448PrivateKeyParameters(InputStream input) throws IOException
{
super(true);
if (KEY_SIZE != Streams.readFully(input, data))
{
throw new EOFException("EOF encountered in middle of X448 private key");
}
}
public void encode(byte[] buf, int off)
{
System.arraycopy(data, 0, buf, off, KEY_SIZE);
}
public byte[] getEncoded()
{
return Arrays.clone(data);
}
public X448PublicKeyParameters generatePublicKey()
{
byte[] publicKey = new byte[X448.POINT_SIZE];
X448.generatePublicKey(data, 0, publicKey, 0);
return new X448PublicKeyParameters(publicKey, 0);
}
public void generateSecret(X448PublicKeyParameters publicKey, byte[] buf, int off)
{
byte[] encoded = new byte[X448.POINT_SIZE];
publicKey.encode(encoded, 0);
if (!X448.calculateAgreement(data, 0, encoded, 0, buf, off))
{
throw new IllegalStateException("X448 agreement failed");
}
}
private static byte[] validate(byte[] buf)
{
if (buf.length != KEY_SIZE)
{
throw new IllegalArgumentException("'buf' must have length " + KEY_SIZE);
}
return buf;
}
}