Question

加密导致错误时出现问题：

javax.crypto.IllegalBlockSizeException: data not block size aligned
    at org.bouncycastle.jcajce.provider.symmetric.util.BaseBlockCipher.engineDoFinal(Unknown Source)
    at javax.crypto.Cipher.doFinal(Cipher.java:2086)
    at com.lcp.sso.logic.SsoCipher.encode(SsoCipher.java:89)

对象的构造函数：

public MyCipher() throws NoSuchAlgorithmException, NoSuchProviderException, NoSuchPaddingException, InvalidKeyException, UnsupportedEncodingException {
    Security.addProvider(new BouncyCastleProvider());
    KeyGenerator keyGen = KeyGenerator.getInstance("DESede", "BC");
    keyGen.init(new SecureRandom());
    SecretKey keySpec = keyGen.generateKey();

    this.sharedKey = keySpec.getEncoded().toString();
    this.encrypter = Cipher.getInstance("DESede/ECB/Nopadding", "BC");
    this.encrypter.init(Cipher.ENCRYPT_MODE, keySpec);
    this.decrypter = Cipher.getInstance("DESede/ECB/Nopadding", "BC");
    this.decrypter.init(Cipher.DECRYPT_MODE, keySpec);
}

发生错误的方法：

public String encode(String arg_text) throws IllegalBlockSizeException, BadPaddingException {
    byte[] encrypt = arg_text.getBytes();

    if(encrypt.length % 8 != 0){ //not a multiple of 8
        //create a new array with a size which is a multiple of 8
        byte[] padded = new byte[encrypt.length + 8 - (encrypt.length % 8)];

        //copy the old array into it
        System.arraycopy(encrypt, 0, padded, 0, encrypt.length);
        encrypt = padded;
    }

    byte[] b = Base64.encodeBase64URLSafe(encrypt);
    return Base64.encodeBase64String(encrypter.doFinal(b));
}

在那里调用最后一个方法时会发生错误。我发誓我正在使它成为正确的块大小，在那里，通过空填充字节数组来确保它是8的倍数。我只是不知道出了什么问题！

我正在使用：
Eclipse版本：Juno Service Release 1
服务器：Localhost的Tomcat v7.0服务器（特别是7.0.32）

--- 编辑 ---

程序尚未运行，（编辑：是的！Muahahahaha！）但问题已解决。

对象的构造函数：

public MyCipher() throws NoSuchAlgorithmException, NoSuchProviderException, NoSuchPaddingException, InvalidKeyException, UnsupportedEncodingException, InvalidParameterSpecException, InvalidAlgorithmParameterException {
    Security.addProvider(new BouncyCastleProvider());
    KeyGenerator keyGen = KeyGenerator.getInstance("DES", "BC");
    keyGen.init(new SecureRandom());
    SecretKey keySpec = keyGen.generateKey();

    this.sharedKey = new String( Base64.encodeBase64URLSafe( keySpec.getEncoded() ) );
    this.encrypter = Cipher.getInstance("DES/CBC/PKCS5Padding", "BC");
    this.encrypter.init(Cipher.ENCRYPT_MODE, keySpec);

    AlgorithmParameters params = this.encrypter.getParameters();
    byte[] iv = params.getParameterSpec(IvParameterSpec.class).getIV();
    IvParameterSpec ivSpec = new IvParameterSpec(iv);

    this.sharedIV = new String( Base64.encodeBase64URLSafe( iv ) );
    this.decrypter = Cipher.getInstance("DES/CBC/PKCS5Padding", "BC");
    this.decrypter.init(Cipher.DECRYPT_MODE, keySpec, ivSpec);
}

加密方法是：

public String encode(String arg_text) throws IllegalBlockSizeException, BadPaddingException, UnsupportedEncodingException {
    byte[] encrypt = arg_text.getBytes();
    return new String( Base64.encodeBase64URLSafe(encrypter.doFinal(encrypt)), "US-ASCII");
}

现在正在努力加密和解密就好了。非常感谢你。

Answer 1

某些方面的奇怪代码。由于您的代码不起作用的原因，您确保encrypt的大小是8的倍数，但您正在尝试加密byte[] b = Base64.encodeBase64URLSafe(encrypt);，这可能不是8的倍数。以下代码应该有效：

public String encode(String arg_text) throws IllegalBlockSizeException, BadPaddingException {
    byte[] encrypt = arg_text.getBytes();

    if(encrypt.length % 8 != 0){ //not a multiple of 8
        //create a new array with a size which is a multiple of 8
        byte[] padded = new byte[encrypt.length + 8 - (encrypt.length % 8)];

        //copy the old array into it
        System.arraycopy(encrypt, 0, padded, 0, encrypt.length);
        encrypt = padded;
    }

    return new String(Base64.encodeBase64URLSafe(encrypter.doFinal(b)), "US-ASCII");
}

现在，有this.encrypter = Cipher.getInstance("DESede/ECB/Nopadding", "BC");的地方你注意到字符串的“Nopadding”部分吗？好吧，代码执行你要求它做的...但是库可以为你做填充工作，你只需要告诉它。请尝试this.encrypter = Cipher.getInstance("DESede/ECB/PKCS5Padding", "BC");，看看它是否有效。

但实际上，为什么要在ECB模式下使用3DES？除非原因是遗产（这在我看到的内容中不太可能），否则没有意义。我相信你需要阅读更多有关密码学的内容。

我阻塞填充，仍然得到“数据不是块大小对齐”

1 个答案: