1

加密时出现问题导致错误：

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。我发誓我正在通过对字节数组进行空填充以确保它是 8 的倍数，从而将其设置为正确的块大小。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：本地主机上的 Tomcat v7.0 服务器（特别是 7.0.32）

---编辑---

程序还没有工作，（编辑：是的！Muahahahaha！）但是这个问题已经解决了。

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");
}

它现在可以很好地加密和解密。非常感谢你。

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1 回答 1

4

某些方面的奇怪代码。从代码不起作用的原因开始，您要确保 的大小encrypt是 8 的倍数，但您正在尝试加密byte[] b = Base64.encodeBase64URLSafe(encrypt);可能不是 8 的倍数。以下代码应该可以工作：

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，您在哪里this.encrypter = Cipher.getInstance("DESede/ECB/Nopadding", "BC");注意到字符串的“N​​opadding”部分？好吧，代码做你要求它做的事情......但是库可以为你做填充工作，你只需要告诉它。试试看this.encrypter = Cipher.getInstance("DESede/ECB/PKCS5Padding", "BC");它是否有效。

但实际上，为什么要在 ECB 模式下使用 3DES？除非原因是遗留问题（从我在这里看到的不太可能），否则没有任何意义。我相信您需要阅读更多有关密码学的内容。

于 2013-02-28T23:32:46.467 回答