PBES2Parameters alg = PBES2Parameters.getInstance(algId.getParameters());
PBKDF2Params func = PBKDF2Params.getInstance(alg.getKeyDerivationFunc().getParameters());
SecretKeyFactory keyFact = SecretKeyFactory.getInstance(alg.getKeyDerivationFunc().getAlgorithm().getId(), bcProvider);
SecretKey k = keyFact.generateSecret(new PBEKeySpec(password, func.getSalt(), func.getIterationCount().intValue(), SecretKeyUtil.getKeySize(alg.getEncryptionScheme().getAlgorithm())));
Cipher cipher = Cipher.getInstance(alg.getEncryptionScheme().getAlgorithm().getId(), bcProvider);
cipher.init(Cipher.UNWRAP_MODE, k, new IvParameterSpec(ASN1OctetString.getInstance(alg.getEncryptionScheme().getParameters()).getOctets()));