让GPG解密工作在Java（BouncyCastle）-GettingGPGDecryptionToWorkInJava(BouncyCastle)

8  

If anyone is interested to know how to encrypt and decrypt gpg files using bouncy castle openPGP library, check the below java code:

如果有人有兴趣知道如何使用bouncy castle openPGP库加密和解密gpg文件，请检查以下java代码：

The below are the 4 methods you going to need:

以下是您需要的4种方法：

The below method will read and import your secret key from .asc file:

以下方法将从.asc文件中读取并导入您的密钥：

public static PGPSecretKey readSecretKeyFromCol(InputStream in, long keyId) throws IOException, PGPException {
    in = PGPUtil.getDecoderStream(in);
    PGPSecretKeyRingCollection pgpSec = new PGPSecretKeyRingCollection(in, new BcKeyFingerprintCalculator());

    PGPSecretKey key = pgpSec.getSecretKey(keyId);

    if (key == null) {
        throw new IllegalArgumentException("Can't find encryption key in key ring.");
    }
    return key;
}

The below method will read and import your public key from .asc file:

以下方法将从.asc文件中读取并导入您的公钥：

@SuppressWarnings("rawtypes")
    public static PGPPublicKey readPublicKeyFromCol(InputStream in) throws IOException, PGPException {
        in = PGPUtil.getDecoderStream(in);
        PGPPublicKeyRingCollection pgpPub = new PGPPublicKeyRingCollection(in, new BcKeyFingerprintCalculator());
        PGPPublicKey key = null;
        Iterator rIt = pgpPub.getKeyRings();
        while (key == null && rIt.hasNext()) {
            PGPPublicKeyRing kRing = (PGPPublicKeyRing) rIt.next();
            Iterator kIt = kRing.getPublicKeys();
            while (key == null && kIt.hasNext()) {
                PGPPublicKey k = (PGPPublicKey) kIt.next();
                if (k.isEncryptionKey()) {
                    key = k;
                }
            }
        }
        if (key == null) {
            throw new IllegalArgumentException("Can't find encryption key in key ring.");
        }
        return key;
    }

The below 2 methods to decrypt and encrypt gpg files:

以下2种解密和加密gpg文件的方法：

public void decryptFile(InputStream in, InputStream secKeyIn, InputStream pubKeyIn, char[] pass) throws IOException, PGPException, InvalidCipherTextException {
        Security.addProvider(new BouncyCastleProvider());

        PGPPublicKey pubKey = readPublicKeyFromCol(pubKeyIn);

        PGPSecretKey secKey = readSecretKeyFromCol(secKeyIn, pubKey.getKeyID());

        in = PGPUtil.getDecoderStream(in);

        JcaPGPObjectFactory pgpFact;


        PGPObjectFactory pgpF = new PGPObjectFactory(in, new BcKeyFingerprintCalculator());

        Object o = pgpF.nextObject();
        PGPEncryptedDataList encList;

        if (o instanceof PGPEncryptedDataList) {

            encList = (PGPEncryptedDataList) o;

        } else {

            encList = (PGPEncryptedDataList) pgpF.nextObject();

        }

        Iterator itt = encList.getEncryptedDataObjects();
        PGPPrivateKey sKey = null;
        PGPPublicKeyEncryptedData encP = null;
        while (sKey == null && itt.hasNext()) {
            encP = itt.next();
            secKey = readSecretKeyFromCol(new FileInputStream("PrivateKey.asc"), encP.getKeyID());
            sKey = secKey.extractPrivateKey(new BcPBESecretKeyDecryptorBuilder(new BcPGPDigestCalculatorProvider()).build(pass));
        }
        if (sKey == null) {
            throw new IllegalArgumentException("Secret key for message not found.");
        }

        InputStream clear = encP.getDataStream(new BcPublicKeyDataDecryptorFactory(sKey));

        pgpFact = new JcaPGPObjectFactory(clear);

        PGPCompressedData c1 = (PGPCompressedData) pgpFact.nextObject();

        pgpFact = new JcaPGPObjectFactory(c1.getDataStream());

        PGPLiteralData ld = (PGPLiteralData) pgpFact.nextObject();
        ByteArrayOutputStream bOut = new ByteArrayOutputStream();

        InputStream inLd = ld.getDataStream();

        int ch;
        while ((ch = inLd.read()) >= 0) {
            bOut.write(ch);
        }

        //System.out.println(bOut.toString());

        bOut.writeTo(new FileOutputStream(ld.getFileName()));
        //return bOut;

    }

    public static void encryptFile(OutputStream out, String fileName, PGPPublicKey encKey) throws IOException, NoSuchProviderException, PGPException {
        Security.addProvider(new BouncyCastleProvider());

        ByteArrayOutputStream bOut = new ByteArrayOutputStream();

        PGPCompressedDataGenerator comData = new PGPCompressedDataGenerator(PGPCompressedData.ZIP);

        PGPUtil.writeFileToLiteralData(comData.open(bOut), PGPLiteralData.BINARY, new File(fileName));

        comData.close();

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

        cPk.addMethod(new BcPublicKeyKeyEncryptionMethodGenerator(encKey));

        byte[] bytes = bOut.toByteArray();

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

        cOut.write(bytes);

        cOut.close();

        out.close();
    }

Now here is how to invoke/run the above:

现在这里是如何调用/运行上面的：

try {
             decryptFile(new FileInputStream("encryptedFile.gpg"), new FileInputStream("PrivateKey.asc"), new FileInputStream("PublicKey.asc"), "yourKeyPassword".toCharArray());

            PGPPublicKey pubKey = readPublicKeyFromCol(new FileInputStream("PublicKey.asc"));

            encryptFile(new FileOutputStream("encryptedFileOutput.gpg"), "fileToEncrypt.txt", pubKey);




        } catch (PGPException e) {
            fail("exception: " + e.getMessage(), e.getUnderlyingException());
        }

2  

I've decided to go with a much different approach, which is to forego the use of bouncy castle altogether and simply use a runtime process instead. For me this solution is working and completely removes the complexity surrounding bouncy castle:

我决定采用一种截然不同的方法，即完全放弃使用充气城堡，而只是简单地使用运行时过程。对我来说，这个解决方案正在发挥作用，完全消除了充气城堡的复杂性：

String[] gpgCommands = new String[] {
        "gpg",
        "--passphrase",
        "password",
        "--decrypt",
        "test-files/accounts.txt.gpg"
};

Process gpgProcess = Runtime.getRuntime().exec(gpgCommands);
BufferedReader gpgOutput = new BufferedReader(new InputStreamReader(gpgProcess.getInputStream()));
BufferedReader gpgError = new BufferedReader(new InputStreamReader(gpgProcess.getErrorStream()));

After doing that you need to remember to drain your input stream as your process is execing or your program will probably hang depending on how much you're outputing. See my answer in this thread (and also that of Cameron Skinner and Matthew Wilson who got me on the proper path) for a bit more context: Calling GnuPG in Java via a Runtime Process to encrypt and decrypt files - Decrypt always hangs

执行此操作后，您需要记住在进程执行时耗尽输入流，否则程序可能会挂起，具体取决于您输出的数量。看看我在这个帖子中的答案（以及Cameron Skinner和Matthew Wilson的答案，让我走上正确的道路）以获得更多上下文：通过运行时进程在Java中调用GnuPG来加密和解密文件 - Decrypt始终挂起

1  

The first Google result is this. It looks like you are trying to decrypt ElGamal data, but you are not passing in an ElGamal key.

谷歌的第一个结果就是这个。看起来您正在尝试解密ElGamal数据，但您没有传入ElGamal密钥。

There are two easy possibilities:

有两种简单的可能性：

• Your keyring collection has multiple keyrings.
• 您的钥匙圈系列有多个钥匙圈。
• Your keyring has subkeys.
• 你的密钥环有子密钥。

You've picked DSA with ElGamal encryption, so I suspect at least the latter: Subkeys are signed by the master key; ElGamal is not a signing algorithm (I don't know if DSA and ElGamal can use the same key, but it's generally seen as a good idea to use different keys for different purposes).

你已经选择了带有ElGamal加密的DSA，所以我怀疑至少是后者：子键是由主密钥签名的; ElGamal不是签名算法（我不知道DSA和ElGamal是否可以使用相同的密钥，但通常认为使用不同密钥用于不同目的是个好主意）。

I think you want something like this (also, secretKeyRing should probably be renamed to secretKeyRingCollection):

我想你想要这样的东西（另外，secretKeyRing应该可以重命名为secretKeyRingCollection）：

PGPSecretKey secretKey = secretKeyRing.getSecretKey(publicKeyEncryptedData.getKeyID());

0  

To any one looking for an alternative solution, see https://stackoverflow.com/a/42176529/7550201

对于寻找替代解决方案的任何人，请参阅https://stackoverflow.com/a/42176529/7550201

final InputStream plaintextStream = BouncyGPG
           .decryptAndVerifyStream()
           .withConfig(keyringConfig)
           .andRequireSignatureFromAllKeys("sender@example.com")
           .fromEncryptedInputStream(cipherTextStream)

Long story short: Bouncycastle is programming is often a lot of cargo cult programming and I wrote a library to change that.

长话短说：Bouncycastle编程通常是很多货物编程，我写了一个库来改变它。