package org.bouncycastle.openpgp.operator.bc;
import java.io.OutputStream;
import java.security.SecureRandom;
import org.bouncycastle.crypto.BlockCipher;
import org.bouncycastle.crypto.BufferedBlockCipher;
import org.bouncycastle.crypto.io.CipherOutputStream;
import org.bouncycastle.openpgp.PGPException;
import org.bouncycastle.openpgp.operator.PGPDataEncryptor;
import org.bouncycastle.openpgp.operator.PGPDataEncryptorBuilder;
import org.bouncycastle.openpgp.operator.PGPDigestCalculator;
public class BcPGPDataEncryptorBuilder
implements PGPDataEncryptorBuilder
{
private SecureRandom random;
private boolean withIntegrityPacket;
private int encAlgorithm;
public BcPGPDataEncryptorBuilder(int encAlgorithm)
{
this.encAlgorithm = encAlgorithm;
if (encAlgorithm == 0)
{
throw new IllegalArgumentException("null cipher specified");
}
}
/**
* Determine whether or not the resulting encrypted data will be protected using an integrity packet.
*
* @param withIntegrityPacket true if an integrity packet is to be included, false otherwise.
* @return the current builder.
*/
public BcPGPDataEncryptorBuilder setWithIntegrityPacket(boolean withIntegrityPacket)
{
this.withIntegrityPacket = withIntegrityPacket;
return this;
}
/**
* Provide a user defined source of randomness.
*
* @param random the secure random to be used.
* @return the current builder.
*/
public BcPGPDataEncryptorBuilder setSecureRandom(SecureRandom random)
{
this.random = random;
return this;
}
public int getAlgorithm()
{
return encAlgorithm;
}
public SecureRandom getSecureRandom()
{
if (random == null)
{
random = new SecureRandom();
}
return random;
}
public PGPDataEncryptor build(byte[] keyBytes)
throws PGPException
{
return new MyPGPDataEncryptor(keyBytes);
}
private class MyPGPDataEncryptor
implements PGPDataEncryptor
{
private final BufferedBlockCipher c;
MyPGPDataEncryptor(byte[] keyBytes)
throws PGPException
{
BlockCipher engine = BcImplProvider.createBlockCipher(encAlgorithm);
try
{
c = BcUtil.createStreamCipher(true, engine, withIntegrityPacket, keyBytes);
}
catch (IllegalArgumentException e)
{
throw new PGPException("invalid parameters: " + e.getMessage(), e);
}
}
public OutputStream getOutputStream(OutputStream out)
{
return new CipherOutputStream(out, c);
}
public PGPDigestCalculator getIntegrityCalculator()
{
if (withIntegrityPacket)
{
return new SHA1PGPDigestCalculator();
}
return null;
}
public int getBlockSize()
{
return c.getBlockSize();
}
}
}