package org.bouncycastle.openpgp.operator.jcajce;
import java.io.IOException;
import java.security.MessageDigest;
import java.security.NoSuchAlgorithmException;
import org.bouncycastle.bcpg.BCPGKey;
import org.bouncycastle.bcpg.MPInteger;
import org.bouncycastle.bcpg.PublicKeyPacket;
import org.bouncycastle.bcpg.RSAPublicBCPGKey;
import org.bouncycastle.openpgp.PGPException;
import org.bouncycastle.openpgp.operator.KeyFingerPrintCalculator;
public class JcaKeyFingerprintCalculator
implements KeyFingerPrintCalculator
{
public byte[] calculateFingerprint(PublicKeyPacket publicPk)
throws PGPException
{
BCPGKey key = publicPk.getKey();
if (publicPk.getVersion() <= 3)
{
RSAPublicBCPGKey rK = (RSAPublicBCPGKey)key;
try
{
MessageDigest digest = MessageDigest.getInstance("MD5");
byte[] bytes = new MPInteger(rK.getModulus()).getEncoded();
digest.update(bytes, 2, bytes.length - 2);
bytes = new MPInteger(rK.getPublicExponent()).getEncoded();
digest.update(bytes, 2, bytes.length - 2);
return digest.digest();
}
catch (NoSuchAlgorithmException e)
{
throw new PGPException("can't find MD5", e);
}
catch (IOException e)
{
throw new PGPException("can't encode key components: " + e.getMessage(), e);
}
}
else
{
try
{
byte[] kBytes = publicPk.getEncodedContents();
MessageDigest digest = MessageDigest.getInstance("SHA1");
digest.update((byte)0x99);
digest.update((byte)(kBytes.length >> 8));
digest.update((byte)kBytes.length);
digest.update(kBytes);
return digest.digest();
}
catch (NoSuchAlgorithmException e)
{
throw new PGPException("can't find SHA1", e);
}
catch (IOException e)
{
throw new PGPException("can't encode key components: " + e.getMessage(), e);
}
}
}
}