Question

我有以下测试代码来加密和解密字符串。如果我在test（）中省略了我的密钥的包装和解包代码，它工作正常，但是当我尝试包装我的密钥，然后再次打开它并将其用于解密时，它失败了，我没有得到“测试“返回作为生成的解密字符串，但改为” J “。

有人看到我正在做的包装和展开错误吗？感谢。

private static void test() throws Exception {

    // create wrap key
    KeyGenerator keyGenerator = KeyGenerator.getInstance("AESWrap");
    keyGenerator.init(256);
    Key wrapKey = keyGenerator.generateKey();

    SecretKey key = generateKey(PASSPHRASE);
    Cipher cipher;

    // wrap key
    cipher = Cipher.getInstance("AESWrap");
    cipher.init(Cipher.WRAP_MODE, wrapKey);
    byte[] wrappedKeyBytes = cipher.wrap(key);

    // unwrap key again
    cipher.init(Cipher.UNWRAP_MODE, wrapKey);
    key = (SecretKey)cipher.unwrap( wrappedKeyBytes, "AES/CTR/NOPADDING", Cipher.SECRET_KEY);

    // encrypt
    cipher = Cipher.getInstance("AES/CTR/NOPADDING");
    cipher.init(Cipher.ENCRYPT_MODE, key, generateIV(cipher), random);
    byte[] b = cipher.doFinal("Test".toString().getBytes());

    // decrypt
    cipher = Cipher.getInstance("AES/CTR/NOPADDING");
    cipher.init(Cipher.DECRYPT_MODE, key, generateIV(cipher), random);
    b = cipher.doFinal(b);

    System.out.println(new String(b));  
    // should output "Test", but outputs �J�� if wrapping/unwrapping

}

以上代码中调用的两个辅助方法：

private static IvParameterSpec generateIV(Cipher cipher) throws Exception {
    byte [] ivBytes = new byte[cipher.getBlockSize()];
    random.nextBytes(ivBytes);    // random = new SecureRandom();
    return new IvParameterSpec(ivBytes);
}

private static SecretKey generateKey(String passphrase) throws Exception {
    PBEKeySpec keySpec = new PBEKeySpec(passphrase.toCharArray(), salt.getBytes(), iterations, keyLength);
    SecretKeyFactory keyFactory = SecretKeyFactory.getInstance(PBE_ALGORITHM); //"PBEWITHSHA256AND256BITAES-CBC-BC"
    return keyFactory.generateSecret(keySpec);
}

Answer 1

看起来你通过调用generateIV（）两次给cipher.init（Cipher.ENCRYPT_MODE，...）和cipher.init（Cipher.DECRYPT_MODE，...）提供了不同的IV。

包装和解包加密密钥失败（javax.crypto）

1 个答案: