Question

我试图在加密后但在写入之前将16字节安全生成的IV附加到每个文件上。这样我以后可以通过拉掉文件中的IV来解密它。到目前为止，这是我的代码：

public static void encrypt(byte[] file, String password, String fileName, String dir)
        throws Exception {
    SecureRandom r = new SecureRandom();
    //128 bit IV generated for each file
    byte[] iv = new byte[IV_LENGTH];
    r.nextBytes(iv);

    SecretKeySpec keySpec = new SecretKeySpec(password.getBytes(), "AES");

    IvParameterSpec ivspec = new IvParameterSpec(iv);
    Cipher cipher = Cipher.getInstance("AES/CBC/NoPadding");
    cipher.init(Cipher.ENCRYPT_MODE, keySpec, ivspec);

    FileOutputStream fos = new FileOutputStream(dir + fileName);
    CipherOutputStream cos = new CipherOutputStream(fos, cipher);

    // Have to append IV --------


    cos.write(file);

    fos.flush();
    cos.flush();
    cos.close();
    fos.close();

有关如何执行此操作的任何建议吗？

Answer 1

FileOutputStream fos = new FileOutputStream(dir + fileName);
fos.write(iv);

CipherOutputStream cos = new CipherOutputStream(fos, cipher);

应该做的伎俩。在设置密码之前，可以将IV写入文件。

将IV附加到加密文件上以便以后解密

1 个答案: