protected int engineGetKeySize(Key key) {
if (!(key instanceof IESKey)) {
throw new IllegalArgumentException("must be passed IE key");
}
IESKey ieKey = (IESKey) key;
if (ieKey.getPrivate() instanceof DHPrivateKey) {
DHPrivateKey k = (DHPrivateKey) ieKey.getPrivate();
return k.getX().bitLength();
} else if (ieKey.getPrivate() instanceof ECPrivateKey) {
ECPrivateKey k = (ECPrivateKey) ieKey.getPrivate();
return k.getD().bitLength();
}
throw new IllegalArgumentException("not an IE key!");
}
protected void engineInit(int opmode, Key key, AlgorithmParameterSpec params, SecureRandom random)
throws InvalidKeyException, InvalidAlgorithmParameterException {
if (!(key instanceof IESKey)) {
throw new InvalidKeyException("must be passed IES key");
}
if (params == null && (opmode == Cipher.ENCRYPT_MODE || opmode == Cipher.WRAP_MODE)) {
//
// if nothing is specified we set up for a 128 bit mac, with
// 128 bit derivation vectors.
//
byte[] d = new byte[16];
byte[] e = new byte[16];
if (random == null) {
random = new SecureRandom();
}
random.nextBytes(d);
random.nextBytes(e);
params = new IESParameterSpec(d, e, 128);
} else if (!(params instanceof IESParameterSpec)) {
throw new InvalidAlgorithmParameterException("must be passed IES parameters");
}
IESKey ieKey = (IESKey) key;
CipherParameters pubKey;
CipherParameters privKey;
if (ieKey.getPublic() instanceof ECPublicKey) {
pubKey = ECUtil.generatePublicKeyParameter(ieKey.getPublic());
privKey = ECUtil.generatePrivateKeyParameter(ieKey.getPrivate());
} else {
pubKey = DHUtil.generatePublicKeyParameter(ieKey.getPublic());
privKey = DHUtil.generatePrivateKeyParameter(ieKey.getPrivate());
}
this.engineParams = (IESParameterSpec) params;
IESParameters p =
new IESParameters(
engineParams.getDerivationV(),
engineParams.getEncodingV(),
engineParams.getMacKeySize());
this.state = opmode;
buffer.reset();
switch (opmode) {
case Cipher.ENCRYPT_MODE:
case Cipher.WRAP_MODE:
cipher.init(true, privKey, pubKey, p);
break;
case Cipher.DECRYPT_MODE:
case Cipher.UNWRAP_MODE:
cipher.init(false, privKey, pubKey, p);
break;
default:
System.out.println("eeek!");
}
}