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尝试解密文件时,java CipherInputStream为空

我正在尝试编写一些助手方法来处理读取和写入加密文件的问题。我有两种方法可以成功地实现这一点,并返回一个InputStream或一个OutputStream(实际上是密码版本),我可以使用它来读取或写入文件。我已经证实,当使用对象流包装并用于将加密对象读写到文件时,这些方法非常有效

然而,当我试图读取加密文本文件时,问题就出现了。我可以验证我输入的字符串是否被加密并写入正确的文件,但当我尝试从该文件读回时,BufferedReader会报告一个EOF(null)。输入流。available()方法返回0。我可以保证文件在那里,正在被找到,并且InputStream本身不是空的。有人能告诉我是什么原因吗

读/写加密对象的工作非常出色(这里的CorruptedStreamException很好):

        private static void testWriteObject() {
    String path = "derp.derp";
    Derp start = new Derp("Asymmetril: " + message, 12543, 21.4, false);
    FilesEnDe.writeEncryptedObject(key, "derp.derp", start);
    echo("original");
    echo(">"+start);

    Object o;
    try {
        ObjectInputStream ois = new ObjectInputStream(ResourceManager.getResourceStatic(path));
        o = ois.readObject();
        echo("encrypted");
        echo(">"+o);
        ois.close();
    } catch (Exception e) {
        e.printStackTrace();
    }

    o = FilesEnDe.readEncryptedObject(key, path);
    echo("decrypted");
    echo(">"+o);
}

输出:

original
>Asymmetril: WE CAME, WE SAW, WE CONQUERED.; 12543; 21.4; false
[RM] > Trying to load resource: derp.derp
java.io.StreamCorruptedException
[RM] > Trying to load resource: derp.derp
decrypted
>Asymmetril: WE CAME, WE SAW, WE CONQUERED.; 12543; 21.4; false

尝试解密文本文件不会(请注意,加密的文本是可读的):

private static void testWriteFile() {
    String path = "EncryptedOut.txt";
    BufferedReader bis1, bis2;

    try {
        BufferedOutputStream os = new BufferedOutputStream(FilesEnDe.getEncryptedOutputStream(key, path));
        os.write(message.getBytes());
        os.flush();
                    os.close();
    } catch (IOException e1) {
        e1.printStackTrace();
    }

    echo("original");
    echo(">"+message);

    try {
        bis1 = new BufferedReader (new InputStreamReader(ResourceManager.getResourceStatic(path)));
        echo("encrypted");
        echo(">" + bis1.readLine());
        bis1.close();
    } catch (IOException e) {
        e.printStackTrace();
    }

    try {
        InputStream is = FilesEnDe.getEncryptedInputStream(key, path);
        InputStreamReader isr = new InputStreamReader(is);
        bis2 = new BufferedReader (isr);
        echo("bits in stream? " + is.available());

        echo("decrypted");
        echo(">"+bis2.readLine());
        bis2.close();
    } catch (IOException e) {
        e.printStackTrace();
    }
    }

输出:

original
>WE CAME, WE SAW, WE CONQUERED.
encrypted
>¤ƒ]£¬Vß4E?´?ùûe
[RM] > Trying to load resource: EncryptedOut.txt
bytes in stream? 0
decrypted
>null

用于创建CipherInputStream的代码:

    public static InputStream getEncryptedInputStream(String key, String path) {
    try {
        InputStream is = ResourceManager.getResourceStatic(path);
        SecretKeySpec keyspec = new SecretKeySpec(getHash(key),"AES");
        Cipher c = Cipher.getInstance("AES");
        c.init(Cipher.DECRYPT_MODE, keyspec);
        return new CipherInputStream(is,c);
    } catch (NoSuchAlgorithmException e) {
        e.printStackTrace();
    } catch (NoSuchPaddingException e) {
        e.printStackTrace();
    } catch (InvalidKeyException e) {
        e.printStackTrace();
    }
    return null;
    }

当我尝试使用CIPHERINPUTSTREAM解密文件并检索原始字符串时,就会出现问题


共 (2) 个答案

  1. # 1 楼答案

    However, the problem arises when I try to read from an encrypted text file.

    没有“加密文本文件”这样的东西。加密的结果是二进制的,而不是文本

    I can verify that the String I feed it is being encrypted and written to the correct file, but when I try to read back from this file, the BufferedReader reports an EOF (null).

    你不应该使用BufferedReader.它不是文本,而是二进制的。使用BufferedInputStream.

  2. # 2 楼答案

    无论我是通过PrintWriter还是BufferedOutputStream写作,也不管我是否使用阅读器阅读。结果,我忘了关闭创建文件的OutputStream。我一加上那一行,一切都开始运转了。感谢Antoniosss建议我重做我的方法中损坏的部分。我想知道为什么Eclipse没有提到关于它的资源泄漏