private void initFromSpec(OAEPParameterSpec pSpec) throws NoSuchPaddingException {
MGF1ParameterSpec mgfParams = (MGF1ParameterSpec) pSpec.getMGFParameters();
Digest digest = DigestFactory.getDigest(mgfParams.getDigestAlgorithm());
if (digest == null) {
throw new NoSuchPaddingException(
"no match on OAEP constructor for digest algorithm: " + mgfParams.getDigestAlgorithm());
}
cipher =
new OAEPEncoding(
new RSABlindedEngine(), digest, ((PSource.PSpecified) pSpec.getPSource()).getValue());
paramSpec = pSpec;
}
protected void engineInit(int opmode, Key key, AlgorithmParameterSpec params, SecureRandom random)
throws InvalidKeyException, InvalidAlgorithmParameterException {
CipherParameters param;
if (params == null || params instanceof OAEPParameterSpec) {
if (key instanceof RSAPublicKey) {
if (privateKeyOnly && opmode == Cipher.ENCRYPT_MODE) {
throw new InvalidKeyException("mode 1 requires RSAPrivateKey");
}
param = RSAUtil.generatePublicKeyParameter((RSAPublicKey) key);
} else if (key instanceof RSAPrivateKey) {
if (publicKeyOnly && opmode == Cipher.ENCRYPT_MODE) {
throw new InvalidKeyException("mode 2 requires RSAPublicKey");
}
param = RSAUtil.generatePrivateKeyParameter((RSAPrivateKey) key);
} else {
throw new InvalidKeyException("unknown key type passed to RSA");
}
if (params != null) {
OAEPParameterSpec spec = (OAEPParameterSpec) params;
paramSpec = params;
if (!spec.getMGFAlgorithm().equalsIgnoreCase("MGF1")
&& !spec.getMGFAlgorithm().equals(PKCSObjectIdentifiers.id_mgf1.getId())) {
throw new InvalidAlgorithmParameterException(
"unknown mask generation function specified");
}
if (!(spec.getMGFParameters() instanceof MGF1ParameterSpec)) {
throw new InvalidAlgorithmParameterException("unkown MGF parameters");
}
Digest digest = DigestFactory.getDigest(spec.getDigestAlgorithm());
if (digest == null) {
throw new InvalidAlgorithmParameterException(
"no match on digest algorithm: " + spec.getDigestAlgorithm());
}
MGF1ParameterSpec mgfParams = (MGF1ParameterSpec) spec.getMGFParameters();
Digest mgfDigest = DigestFactory.getDigest(mgfParams.getDigestAlgorithm());
if (mgfDigest == null) {
throw new InvalidAlgorithmParameterException(
"no match on MGF digest algorithm: " + mgfParams.getDigestAlgorithm());
}
cipher =
new OAEPEncoding(
new RSABlindedEngine(),
digest,
mgfDigest,
((PSource.PSpecified) spec.getPSource()).getValue());
}
} else {
throw new InvalidAlgorithmParameterException(
"unknown parameter type: " + params.getClass().getName());
}
if (!(cipher instanceof RSABlindedEngine)) {
if (random != null) {
param = new ParametersWithRandom(param, random);
} else {
param = new ParametersWithRandom(param, new SecureRandom());
}
}
bOut.reset();
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:
throw new InvalidParameterException("unknown opmode " + opmode + " passed to RSA");
}
}