Java中使用BouncyCastle PGP实用程序进行增量加密

Question

我正在尝试编写一个加密文件，它将使用gpg解密，并将以增量方式写入行，而不是在一个块中。我已经在GnuPG中生成了密钥，并且正在使用公钥加密。下面是我正在使用的加密方法：

  public static byte[] encrypt(byte[] clearData, PGPPublicKey encKey,
            String fileName,boolean withIntegrityCheck, boolean armor)
            throws IOException, PGPException, NoSuchProviderException {
        if (fileName == null) {
            fileName = PGPLiteralData.CONSOLE;
        }

        ByteArrayOutputStream encOut = new ByteArrayOutputStream();

        OutputStream out = encOut;
        if (armor) {
            out = new ArmoredOutputStream(out);
        }

        ByteArrayOutputStream bOut = new ByteArrayOutputStream();

        PGPCompressedDataGenerator comData = new PGPCompressedDataGenerator(
                PGPCompressedDataGenerator.ZIP);
        OutputStream cos = comData.open(bOut); // open it with the final
        // destination
        PGPLiteralDataGenerator lData = new PGPLiteralDataGenerator();

        // we want to generate compressed data. This might be a user option
        // later,
        // in which case we would pass in bOut.
        OutputStream pOut = lData.open(cos, // the compressed output stream
                PGPLiteralData.BINARY, fileName, // "filename" to store
                clearData.length, // length of clear data
                new Date() // current time
                );
        pOut.write(clearData);

        lData.close();
        comData.close();

        PGPEncryptedDataGenerator cPk = new PGPEncryptedDataGenerator(new BcPGPDataEncryptorBuilder(SymmetricKeyAlgorithmTags.AES_192).setSecureRandom(new SecureRandom()));


        cPk.addMethod(new BcPublicKeyKeyEncryptionMethodGenerator(encKey));

        byte[] bytes = bOut.toByteArray();

        OutputStream cOut = cPk.open(out, bytes.length);

        cOut.write(bytes); // obtain the actual bytes from the compressed stream

        cOut.close();

        out.close();

        return encOut.toByteArray();
    }

我有一个小的原型测试类来使用这种方法：

            PGPPublicKey pubKey = PGPEncryptionTools.readPublicKeyFromCol(new FileInputStream(appProp.getKeyFileName()));

        byte[] encryptbytes = PGPEncryptionTools.encrypt("\nthis is some test text".getBytes(), pubKey, null, true, false);
        byte[] encryptbytes2 = PGPEncryptionTools.encrypt("\nmore test text".getBytes(), pubKey, null, true, false);

        FileOutputStream fos = new FileOutputStream("C:/Users/me/workspace/workspace/spring-batch-project/resources/encryptedfile.gpg");
        fos.write(encryptbytes);
        fos.write(encryptbytes2);
        fos.flush();
        fos.close();

我怎样才能修改这段代码，使它既能加密两行，又能让GnuPG解密它们呢？

Answer 1

每次调用PGPEncryptionTools.Encrypt(...)方法时，都会生成多个独立的OpenPGP消息。要只输出单个OpenPGP消息（GnuPG也在一次运行中解密该消息），请将所有纯文本写入单个流（在代码中称为pout)，并且在将最后一个字节写入流之前不要关闭该消息。