Cipher createCipher(String cipherName) throws PGPException {
try {
return helper.createCipher(cipherName);
} catch (NoSuchAlgorithmException e) {
throw new PGPException("cannot create cipher: " + e.getMessage(), e);
} catch (NoSuchPaddingException e) {
throw new PGPException("cannot create cipher: " + e.getMessage(), e);
} catch (NoSuchProviderException e) {
throw new PGPException("cannot create cipher: " + e.getMessage(), e);
}
}
Cipher createKeyWrapper(int encAlgorithm) throws PGPException {
try {
switch (encAlgorithm) {
case SymmetricKeyAlgorithmTags.AES_128:
case SymmetricKeyAlgorithmTags.AES_192:
case SymmetricKeyAlgorithmTags.AES_256:
return helper.createCipher("AESWrap");
case SymmetricKeyAlgorithmTags.CAMELLIA_128:
case SymmetricKeyAlgorithmTags.CAMELLIA_192:
case SymmetricKeyAlgorithmTags.CAMELLIA_256:
return helper.createCipher("CamelliaWrap");
default:
throw new PGPException("unknown wrap algorithm: " + encAlgorithm);
}
} catch (NoSuchAlgorithmException e) {
throw new PGPException("cannot create cipher: " + e.getMessage(), e);
} catch (NoSuchPaddingException e) {
throw new PGPException("cannot create cipher: " + e.getMessage(), e);
} catch (NoSuchProviderException e) {
throw new PGPException("cannot create cipher: " + e.getMessage(), e);
}
}
public OutputEncryptor build(final char[] password) throws OperatorCreationException {
final Cipher cipher;
SecretKey key;
if (random == null) {
random = new SecureRandom();
}
final AlgorithmIdentifier encryptionAlg;
final byte[] salt = new byte[20];
final int iterationCount = 1024;
random.nextBytes(salt);
try {
if (algorithm.on(PKCSObjectIdentifiers.pkcs_12PbeIds)) {
PBEKeySpec pbeSpec = new PBEKeySpec(password);
SecretKeyFactory keyFact = helper.createSecretKeyFactory(algorithm.getId());
PBEParameterSpec defParams = new PBEParameterSpec(salt, iterationCount);
key = keyFact.generateSecret(pbeSpec);
cipher = helper.createCipher(algorithm.getId());
cipher.init(Cipher.ENCRYPT_MODE, key, defParams);
encryptionAlg =
new AlgorithmIdentifier(algorithm, new PKCS12PBEParams(salt, iterationCount));
} else if (algorithm.equals(PKCSObjectIdentifiers.id_PBES2)) {
SecretKeyFactory keyFact =
helper.createSecretKeyFactory(PKCSObjectIdentifiers.id_PBKDF2.getId());
key =
keyFact.generateSecret(
new PBEKeySpec(
password,
salt,
iterationCount,
keySizeProvider.getKeySize(new AlgorithmIdentifier(keyEncAlgorithm))));
cipher = helper.createCipher(keyEncAlgorithm.getId());
cipher.init(Cipher.ENCRYPT_MODE, key, random);
PBES2Parameters algParams =
new PBES2Parameters(
new KeyDerivationFunc(
PKCSObjectIdentifiers.id_PBKDF2, new PBKDF2Params(salt, iterationCount)),
new EncryptionScheme(
keyEncAlgorithm,
ASN1Primitive.fromByteArray(cipher.getParameters().getEncoded())));
encryptionAlg = new AlgorithmIdentifier(algorithm, algParams);
} else {
throw new OperatorCreationException("unrecognised algorithm");
}
return new OutputEncryptor() {
public AlgorithmIdentifier getAlgorithmIdentifier() {
return encryptionAlg;
}
public OutputStream getOutputStream(OutputStream out) {
return new CipherOutputStream(out, cipher);
}
public GenericKey getKey() {
if (isPKCS12(encryptionAlg.getAlgorithm())) {
return new GenericKey(
encryptionAlg, PBEParametersGenerator.PKCS5PasswordToBytes(password));
} else {
return new GenericKey(
encryptionAlg, PBEParametersGenerator.PKCS12PasswordToBytes(password));
}
}
};
} catch (Exception e) {
throw new OperatorCreationException("unable to create OutputEncryptor: " + e.getMessage(), e);
}
}