protected void engineInit(int opmode, Key key, AlgorithmParameterSpec params, SecureRandom random)
throws InvalidKeyException, InvalidAlgorithmParameterException {
CipherParameters param;
this.pbeSpec = null;
this.pbeAlgorithm = null;
this.engineParams = null;
//
// basic key check
//
if (!(key instanceof SecretKey)) {
throw new InvalidKeyException(
"Key for algorithm " + key.getAlgorithm() + " not suitable for symmetric enryption.");
}
if (key instanceof BCPBEKey) {
BCPBEKey k = (BCPBEKey) key;
if (k.getOID() != null) {
pbeAlgorithm = k.getOID().getId();
} else {
pbeAlgorithm = k.getAlgorithm();
}
if (k.getParam() != null) {
param = k.getParam();
pbeSpec = new PBEParameterSpec(k.getSalt(), k.getIterationCount());
} else if (params instanceof PBEParameterSpec) {
param = PBE.Util.makePBEParameters(k, params, cipher.getAlgorithmName());
pbeSpec = (PBEParameterSpec) params;
} else {
throw new InvalidAlgorithmParameterException("PBE requires PBE parameters to be set.");
}
if (k.getIvSize() != 0) {
ivParam = (ParametersWithIV) param;
}
} else if (params == null) {
param = new KeyParameter(key.getEncoded());
} else if (params instanceof IvParameterSpec) {
param =
new ParametersWithIV(
new KeyParameter(key.getEncoded()), ((IvParameterSpec) params).getIV());
ivParam = (ParametersWithIV) param;
} else {
throw new IllegalArgumentException("unknown parameter type.");
}
if ((ivLength != 0) && !(param instanceof ParametersWithIV)) {
SecureRandom ivRandom = random;
if (ivRandom == null) {
ivRandom = new SecureRandom();
}
if ((opmode == Cipher.ENCRYPT_MODE) || (opmode == Cipher.WRAP_MODE)) {
byte[] iv = new byte[ivLength];
ivRandom.nextBytes(iv);
param = new ParametersWithIV(param, iv);
ivParam = (ParametersWithIV) param;
} else {
throw new InvalidAlgorithmParameterException("no IV set when one expected");
}
}
switch (opmode) {
case Cipher.ENCRYPT_MODE:
case Cipher.WRAP_MODE:
cipher.init(true, param);
break;
case Cipher.DECRYPT_MODE:
case Cipher.UNWRAP_MODE:
cipher.init(false, param);
break;
default:
System.out.println("eeek!");
}
}