package org.bouncycastle.jcajce.provider.asymmetric.ec;
import java.io.ByteArrayOutputStream;
import java.security.AlgorithmParameters;
import java.security.InvalidAlgorithmParameterException;
import java.security.InvalidKeyException;
import java.security.Key;
import java.security.NoSuchAlgorithmException;
import java.security.PrivateKey;
import java.security.PublicKey;
import java.security.SecureRandom;
import java.security.spec.AlgorithmParameterSpec;
import javax.crypto.BadPaddingException;
import javax.crypto.Cipher;
import javax.crypto.CipherSpi;
import javax.crypto.IllegalBlockSizeException;
import javax.crypto.NoSuchPaddingException;
import javax.crypto.ShortBufferException;
import org.bouncycastle.crypto.InvalidCipherTextException;
import org.bouncycastle.crypto.KeyEncoder;
import org.bouncycastle.crypto.agreement.ECDHBasicAgreement;
import org.bouncycastle.crypto.digests.SHA1Digest;
import org.bouncycastle.crypto.engines.AESEngine;
import org.bouncycastle.crypto.engines.DESedeEngine;
import org.bouncycastle.crypto.engines.IESEngine;
import org.bouncycastle.crypto.generators.ECKeyPairGenerator;
import org.bouncycastle.crypto.generators.EphemeralKeyPairGenerator;
import org.bouncycastle.crypto.generators.KDF2BytesGenerator;
import org.bouncycastle.crypto.macs.HMac;
import org.bouncycastle.crypto.paddings.PaddedBufferedBlockCipher;
import org.bouncycastle.crypto.params.AsymmetricKeyParameter;
import org.bouncycastle.crypto.params.ECDomainParameters;
import org.bouncycastle.crypto.params.ECKeyGenerationParameters;
import org.bouncycastle.crypto.params.ECKeyParameters;
import org.bouncycastle.crypto.params.ECPublicKeyParameters;
import org.bouncycastle.crypto.params.IESParameters;
import org.bouncycastle.crypto.params.IESWithCipherParameters;
import org.bouncycastle.crypto.parsers.ECIESPublicKeyParser;
import org.bouncycastle.jcajce.provider.asymmetric.util.ECUtil;
import org.bouncycastle.jcajce.provider.asymmetric.util.IESUtil;
import org.bouncycastle.jce.interfaces.ECKey;
import org.bouncycastle.jce.interfaces.ECPrivateKey;
import org.bouncycastle.jce.interfaces.ECPublicKey;
import org.bouncycastle.jce.interfaces.IESKey;
import org.bouncycastle.jce.provider.BouncyCastleProvider;
import org.bouncycastle.jce.spec.IESParameterSpec;
import org.bouncycastle.util.Strings;
public class IESCipher
extends CipherSpi
{
private IESEngine engine;
private int state = -1;
private ByteArrayOutputStream buffer = new ByteArrayOutputStream();
private AlgorithmParameters engineParam = null;
private IESParameterSpec engineSpec = null;
private AsymmetricKeyParameter key;
private SecureRandom random;
private boolean dhaesMode = false;
private AsymmetricKeyParameter otherKeyParameter = null;
public IESCipher(IESEngine engine)
{
this.engine = engine;
}
public int engineGetBlockSize()
{
if (engine.getCipher() != null)
{
return engine.getCipher().getBlockSize();
}
else
{
return 0;
}
}
public int engineGetKeySize(Key key)
{
if (key instanceof ECKey)
{
return ((ECKey)key).getParameters().getCurve().getFieldSize();
}
else
{
throw new IllegalArgumentException("not an EC key");
}
}
public byte[] engineGetIV()
{
return null;
}
public AlgorithmParameters engineGetParameters()
{
if (engineParam == null && engineSpec != null)
{
try
{
engineParam = AlgorithmParameters.getInstance("IES", BouncyCastleProvider.PROVIDER_NAME);
engineParam.init(engineSpec);
}
catch (Exception e)
{
throw new RuntimeException(e.toString());
}
}
return engineParam;
}
public void engineSetMode(String mode)
throws NoSuchAlgorithmException
{
String modeName = Strings.toUpperCase(mode);
if (modeName.equals("NONE"))
{
dhaesMode = false;
}
else if (modeName.equals("DHAES"))
{
dhaesMode = true;
}
else
{
throw new IllegalArgumentException("can't support mode " + mode);
}
}
public int engineGetOutputSize(int inputLen)
{
int len1, len2, len3;
len1 = engine.getMac().getMacSize();
if (key != null)
{
len2 = 1 + 2 * (((ECKey)key).getParameters().getCurve().getFieldSize() + 7) / 8;
}
else
{
throw new IllegalStateException("cipher not initialised");
}
if (engine.getCipher() == null)
{
len3 = inputLen;
}
else if (state == Cipher.ENCRYPT_MODE || state == Cipher.WRAP_MODE)
{
len3 = engine.getCipher().getOutputSize(inputLen);
}
else if (state == Cipher.DECRYPT_MODE || state == Cipher.UNWRAP_MODE)
{
len3 = engine.getCipher().getOutputSize(inputLen - len1 - len2);
}
else
{
throw new IllegalStateException("cipher not initialised");
}
if (state == Cipher.ENCRYPT_MODE || state == Cipher.WRAP_MODE)
{
return buffer.size() + len1 + len2 + len3;
}
else if (state == Cipher.DECRYPT_MODE || state == Cipher.UNWRAP_MODE)
{
return buffer.size() - len1 - len2 + len3;
}
else
{
throw new IllegalStateException("cipher not initialised");
}
}
public void engineSetPadding(String padding)
throws NoSuchPaddingException
{
String paddingName = Strings.toUpperCase(padding);
// TDOD: make this meaningful...
if (paddingName.equals("NOPADDING"))
{
}
else if (paddingName.equals("PKCS5PADDING") || paddingName.equals("PKCS7PADDING"))
{
}
else
{
throw new NoSuchPaddingException("padding not available with IESCipher");
}
}
// Initialisation methods
public void engineInit(
int opmode,
Key key,
AlgorithmParameters params,
SecureRandom random)
throws InvalidKeyException, InvalidAlgorithmParameterException
{
AlgorithmParameterSpec paramSpec = null;
if (params != null)
{
try
{
paramSpec = params.getParameterSpec(IESParameterSpec.class);
}
catch (Exception e)
{
throw new InvalidAlgorithmParameterException("cannot recognise parameters: " + e.toString());
}
}
engineParam = params;
engineInit(opmode, key, paramSpec, random);
}
public void engineInit(
int opmode,
Key key,
AlgorithmParameterSpec engineSpec,
SecureRandom random)
throws InvalidAlgorithmParameterException, InvalidKeyException
{
otherKeyParameter = null;
// Use default parameters (including cipher key size) if none are specified
if (engineSpec == null)
{
this.engineSpec = IESUtil.guessParameterSpec(engine);
}
else if (engineSpec instanceof IESParameterSpec)
{
this.engineSpec = (IESParameterSpec)engineSpec;
}
else
{
throw new InvalidAlgorithmParameterException("must be passed IES parameters");
}
// Parse the recipient's key
if (opmode == Cipher.ENCRYPT_MODE || opmode == Cipher.WRAP_MODE)
{
if (key instanceof ECPublicKey)
{
this.key = ECUtil.generatePublicKeyParameter((PublicKey)key);
}
else if (key instanceof IESKey)
{
IESKey ieKey = (IESKey)key;
this.key = ECUtil.generatePublicKeyParameter(ieKey.getPublic());
this.otherKeyParameter = ECUtil.generatePrivateKeyParameter(ieKey.getPrivate());
}
else
{
throw new InvalidKeyException("must be passed recipient's public EC key for encryption");
}
}
else if (opmode == Cipher.DECRYPT_MODE || opmode == Cipher.UNWRAP_MODE)
{
if (key instanceof ECPrivateKey)
{
this.key = ECUtil.generatePrivateKeyParameter((PrivateKey)key);
}
else if (key instanceof IESKey)
{
IESKey ieKey = (IESKey)key;
this.otherKeyParameter = ECUtil.generatePublicKeyParameter(ieKey.getPublic());
this.key = ECUtil.generatePrivateKeyParameter(ieKey.getPrivate());
}
else
{
throw new InvalidKeyException("must be passed recipient's private EC key for decryption");
}
}
else
{
throw new InvalidKeyException("must be passed EC key");
}
this.random = random;
this.state = opmode;
buffer.reset();
}
public void engineInit(
int opmode,
Key key,
SecureRandom random)
throws InvalidKeyException
{
try
{
engineInit(opmode, key, (AlgorithmParameterSpec)null, random);
}
catch (InvalidAlgorithmParameterException e)
{
throw new IllegalArgumentException("can't handle supplied parameter spec");
}
}
// Update methods - buffer the input
public byte[] engineUpdate(
byte[] input,
int inputOffset,
int inputLen)
{
buffer.write(input, inputOffset, inputLen);
return null;
}
public int engineUpdate(
byte[] input,
int inputOffset,
int inputLen,
byte[] output,
int outputOffset)
{
buffer.write(input, inputOffset, inputLen);
return 0;
}
// Finalisation methods
public byte[] engineDoFinal(
byte[] input,
int inputOffset,
int inputLen)
throws IllegalBlockSizeException, BadPaddingException
{
if (inputLen != 0)
{
buffer.write(input, inputOffset, inputLen);
}
final byte[] in = buffer.toByteArray();
buffer.reset();
// Convert parameters for use in IESEngine
IESParameters params = new IESWithCipherParameters(engineSpec.getDerivationV(),
engineSpec.getEncodingV(),
engineSpec.getMacKeySize(),
engineSpec.getCipherKeySize());
final ECDomainParameters ecParams = ((ECKeyParameters)key).getParameters();
final byte[] V;
if (otherKeyParameter != null)
{
try
{
if (state == Cipher.ENCRYPT_MODE || state == Cipher.WRAP_MODE)
{
engine.init(true, otherKeyParameter, key, params);
}
else
{
engine.init(false, key, otherKeyParameter, params);
}
return engine.processBlock(in, 0, in.length);
}
catch (Exception e)
{
throw new BadPaddingException(e.getMessage());
}
}
if (state == Cipher.ENCRYPT_MODE || state == Cipher.WRAP_MODE)
{
// Generate the ephemeral key pair
ECKeyPairGenerator gen = new ECKeyPairGenerator();
gen.init(new ECKeyGenerationParameters(ecParams, random));
EphemeralKeyPairGenerator kGen = new EphemeralKeyPairGenerator(gen, new KeyEncoder()
{
public byte[] getEncoded(AsymmetricKeyParameter keyParameter)
{
return ((ECPublicKeyParameters)keyParameter).getQ().getEncoded();
}
});
// Encrypt the buffer
try
{
engine.init(key, params, kGen);
return engine.processBlock(in, 0, in.length);
}
catch (Exception e)
{
throw new BadPaddingException(e.getMessage());
}
}
else if (state == Cipher.DECRYPT_MODE || state == Cipher.UNWRAP_MODE)
{
// Decrypt the buffer
try
{
engine.init(key, params, new ECIESPublicKeyParser(ecParams));
return engine.processBlock(in, 0, in.length);
}
catch (InvalidCipherTextException e)
{
throw new BadPaddingException(e.getMessage());
}
}
else
{
throw new IllegalStateException("cipher not initialised");
}
}
public int engineDoFinal(
byte[] input,
int inputOffset,
int inputLength,
byte[] output,
int outputOffset)
throws ShortBufferException, IllegalBlockSizeException, BadPaddingException
{
byte[] buf = engineDoFinal(input, inputOffset, inputLength);
System.arraycopy(buf, 0, output, outputOffset, buf.length);
return buf.length;
}
/**
* Classes that inherit from us
*/
static public class ECIES
extends IESCipher
{
public ECIES()
{
super(new IESEngine(new ECDHBasicAgreement(),
new KDF2BytesGenerator(new SHA1Digest()),
new HMac(new SHA1Digest())));
}
}
static public class ECIESwithDESede
extends IESCipher
{
public ECIESwithDESede()
{
super(new IESEngine(new ECDHBasicAgreement(),
new KDF2BytesGenerator(new SHA1Digest()),
new HMac(new SHA1Digest()),
new PaddedBufferedBlockCipher(new DESedeEngine())));
}
}
static public class ECIESwithAES
extends IESCipher
{
public ECIESwithAES()
{
super(new IESEngine(new ECDHBasicAgreement(),
new KDF2BytesGenerator(new SHA1Digest()),
new HMac(new SHA1Digest()),
new PaddedBufferedBlockCipher(new AESEngine())));
}
}
}