Java 加密不会在 Android 上解密

Question

好的，所以当我加密任何东西时，让我们说在这种情况下是一个文件，用我的电脑。它可以很好地加密和解密所述文件。但是，如果用我的计算机加密文件，然后将它发送给我的 android 并运行我编写的相同解密代码，它不会正确解密文件。它没有显示任何错误，但是文件显然没有正确解密。

所以我了解到 Bouncy Castle 与 JVM/JDK 标准加密库完全不同，所以我不能 100% 确定这是否是问题所在。然而，这将是有道理的。问题是，如果是我不知道如何在我的 android 上使用 JVM/JDK 库进行加密。我不想在我的电脑上使用 Bouncy Castle 库。

public static void encrypt(File source, File dest, String password){
    try{
        FileInputStream inFile = new FileInputStream(source.getPath());
        FileOutputStream outFile = new FileOutputStream(dest.getPath());

        byte[] salt = new byte[8], iv = new byte[16];

        SecretKeyFactory factory = SecretKeyFactory.getInstance("PBKDF2WithHmacSHA1");
        KeySpec keySpec = new PBEKeySpec(password.toCharArray(), salt, 65536, 256);
        SecretKey secretKey = factory.generateSecret(keySpec);
        SecretKey secret = new SecretKeySpec(secretKey.getEncoded(), "AES");

        Cipher cipher = Cipher.getInstance("AES/CBC/PKCS5Padding");
        cipher.init(Cipher.ENCRYPT_MODE, secret, new IvParameterSpec(iv));

        byte[] input = new byte[64];
        int bytesRead;

        while((bytesRead = inFile.read(input)) != -1){
            byte[] output = cipher.update(input, 0, bytesRead);
            if(output != null){
                outFile.write(output);
            }
        }

        byte[] output = cipher.doFinal();
        if(output != null){
            outFile.write(output);
        }

        inFile.close();
        outFile.flush();
        outFile.close();
    }catch(Exception e){
        e.printStackTrace();
    }
}

public static void decrypt(File source, File dest, String password){
    try{
        byte[] salt = new byte[8], iv = new byte[16];

        SecretKeyFactory factory = SecretKeyFactory.getInstance("PBKDF2WithHmacSHA1");
        KeySpec keySpec = new PBEKeySpec(password.toCharArray(), salt, 65536, 256);
        SecretKey tmp = factory.generateSecret(keySpec);
        SecretKey secret = new SecretKeySpec(tmp.getEncoded(), "AES");

        Cipher cipher = Cipher.getInstance("AES/CBC/PKCS5Padding");
        cipher.init(Cipher.DECRYPT_MODE, secret, new IvParameterSpec(iv));
        FileInputStream fis = new FileInputStream(source.getPath());
        FileOutputStream fos = new FileOutputStream(dest.getPath());
        byte[] in = new byte[64];
        int read;
        while((read = fis.read(in)) != -1){
            byte[] output = cipher.update(in, 0, read);
            if(output != null){
                fos.write(output);
            }
        }

        byte[] output = cipher.doFinal();
        if(output != null){
            fos.write(output);
        }
        fis.close();
        fos.flush();
        fos.close();
    }catch(Exception e){
        e.printStackTrace();
    }
}

结果也将能够使用我的计算机使用标准 JVM/JDK 加密库加密任何文件，并且也能够使用我的 android 解密相同的文件。

但是，如果除了 Bouncy Castle 之外还有其他可以与 android 一起使用的库，我愿意提供想法。

Answer 1

我也遇到过类似的问题。首先检查您的加密和解密设置是否正确。

如果没问题，那么您应该将加密文本转换为 Base64 或类似编码。

然后在手机上先解码Base64编码再解密文件。

出现此问题的原因是，某些字符不适合在媒体之间保存或传输。它们也会受到底层操作系统的影响。即使有一点改变，你的整个解密文本也会改变，这里可能就是这种情况

安卓代码

public static void decrypt(File source, File dest, String password){
    try{
        Base64InputStream fis = new Base64InputStream(new DataInputStream(new FileInputStream(source.getPath())), Base64.DEFAULT);
        FileOutputStream fos = new FileOutputStream(dest.getPath());


        byte[] salt = new byte[8], iv = new byte[16];

        SecretKeyFactory factory = SecretKeyFactory.getInstance("PBKDF2WithHmacSHA1");
        KeySpec keySpec = new PBEKeySpec(password.toCharArray(), salt, 65536, 256);
        SecretKey tmp = factory.generateSecret(keySpec);
        SecretKey secret = new SecretKeySpec(tmp.getEncoded(), "AES");

        Cipher cipher = Cipher.getInstance("AES/CBC/PKCS5Padding");
        cipher.init(Cipher.DECRYPT_MODE, secret, new IvParameterSpec(iv));

        byte[] in = new byte[64];
        int read;
        while((read = fis.read(in)) != -1){
            byte[] output = cipher.update(in, 0, read);
            if(output != null){
                fos.write(output);
            }
        }

        byte[] output = cipher.doFinal();
        if(output != null){
            fos.write(output);
        }
        fis.close();
        fos.flush();
        fos.close();
    }catch(Exception e){
        e.printStackTrace();
    }
}

常规 JVM

public static void encrypt(File source, File dest, String password){
    try{
        FileInputStream inFile = new FileInputStream(source.getPath());
        OutputStream outFile = Base64.getEncoder().wrap(new FileOutputStream(dest.getPath()));

        byte[] salt = new byte[8], iv = new byte[16];

        SecretKeyFactory factory = SecretKeyFactory.getInstance("PBKDF2WithHmacSHA1");
        KeySpec keySpec = new PBEKeySpec(password.toCharArray(), salt, 65536, 256);
        SecretKey secretKey = factory.generateSecret(keySpec);
        SecretKey secret = new SecretKeySpec(secretKey.getEncoded(), "AES");

        Cipher cipher = Cipher.getInstance("AES/CBC/PKCS5Padding");
        cipher.init(Cipher.ENCRYPT_MODE, secret, new IvParameterSpec(iv));

        byte[] input = new byte[64];
        int bytesRead;

        while((bytesRead = inFile.read(input)) != -1){
            byte[] output = cipher.update(input, 0, bytesRead);
            if(output != null){
                outFile.write(output);
            }
        }

        byte[] output = cipher.doFinal();
        if(output != null){
            outFile.write(output);
        }

        inFile.close();
        outFile.flush();
        outFile.close();
    }catch(Exception e){
        e.printStackTrace();
    }
}

public static void decrypt(File source, File dest, String password){
    try{
        InputStream fis = Base64.getDecoder().wrap(new FileInputStream(source.getPath()));
        //FileInputStream fis = new FileInputStream(source.getPath());
        FileOutputStream fos = new FileOutputStream(dest.getPath());

        byte[] salt = new byte[8], iv = new byte[16];

        SecretKeyFactory factory = SecretKeyFactory.getInstance("PBKDF2WithHmacSHA1");
        KeySpec keySpec = new PBEKeySpec(password.toCharArray(), salt, 65536, 256);
        SecretKey tmp = factory.generateSecret(keySpec);
        SecretKey secret = new SecretKeySpec(tmp.getEncoded(), "AES");

        Cipher cipher = Cipher.getInstance("AES/CBC/PKCS5Padding");
        cipher.init(Cipher.DECRYPT_MODE, secret, new IvParameterSpec(iv));

        byte[] in = new byte[64];
        int read;
        while((read = fis.read(in)) != -1){
            byte[] output = cipher.update(in, 0, read);
            if(output != null){
                fos.write(output);
            }
        }

        byte[] output = cipher.doFinal();
        if(output != null){
            fos.write(output);
        }
        fis.close();
        fos.flush();
        fos.close();
    }catch(Exception e){
        e.printStackTrace();
    }
}