PHP Java AES CBC加密不同的结果

Question

PHP功能:

$privateKey = "1234567812345678";
$iv = "1234567812345678";
$data = "Test string";

$encrypted = mcrypt_encrypt(MCRYPT_RIJNDAEL_128, $privateKey, $data, MCRYPT_MODE_CBC, $iv);

echo(base64_encode($encrypted));

Result: iz1qFlQJfs6Ycp+gcc2z4w==

---

Java函数

public static String encrypt() throws Exception{
try{
    String data = "Test string";
    String key = "1234567812345678";
    String iv = "1234567812345678";

    javax.crypto.spec.SecretKeySpec keyspec = new javax.crypto.spec.SecretKeySpec(key.getBytes(), "AES");
    javax.crypto.spec.IvParameterSpec ivspec = new javax.crypto.spec.IvParameterSpec(iv.getBytes());

    javax.crypto.Cipher cipher = javax.crypto.Cipher.getInstance("AES/CBC/NoPadding");
    cipher.init(javax.crypto.Cipher.ENCRYPT_MODE, keyspec, ivspec);
    byte[] encrypted = cipher.doFinal(data.getBytes());

    return new sun.misc.BASE64Encoder().encode(encrypted);

}catch(Exception e){
    return null;
}

}

返回null.

请注意,我们不允许更改PHP代码.有人可以帮助我们在Java中获得相同的结果吗？非常感谢.

Answer 1

你有什么事情,如果你并没有简单地吞掉可能更好的主意Exception是你的内部encrypt()程序.如果您的函数正在返回,null那么很明显发生了异常,您需要知道它是什么.

事实上,例外是:

javax.crypto.IllegalBlockSizeException: Input length not multiple of 16 bytes
    at com.sun.crypto.provider.CipherCore.finalNoPadding(CipherCore.java:854)
    at com.sun.crypto.provider.CipherCore.doFinal(CipherCore.java:828)
    at com.sun.crypto.provider.CipherCore.doFinal(CipherCore.java:676)
    at com.sun.crypto.provider.AESCipher.engineDoFinal(AESCipher.java:313)
    at javax.crypto.Cipher.doFinal(Cipher.java:2087)
    at Encryption.encrypt(Encryption.java:20)
    at Encryption.main(Encryption.java:6)

当然,你的纯文本只有11个Java字符长,在你的默认编码中,它将是11个字节.

您需要检查PHP mcrypt_encrypt函数实际执行的操作.由于它的工作原理,它显然使用了一些填充方案.您需要找出它是哪一个并在Java代码中使用它.

好的 - 我查了手册页mcrypt_encrypt.它说:

将使用给定的密码和模式加密的数据.如果数据的大小不是n * blocksize,则数据将被填充\0.

所以你需要在Java中复制它.这是一种方式:

import javax.crypto.Cipher;
import javax.crypto.spec.IvParameterSpec;
import javax.crypto.spec.SecretKeySpec;

public class Encryption
{
    public static void main(String args[]) throws Exception {
        System.out.println(encrypt());
    }

    public static String encrypt() throws Exception {
        try {
            String data = "Test string";
            String key = "1234567812345678";
            String iv = "1234567812345678";

            Cipher cipher = Cipher.getInstance("AES/CBC/NoPadding");
            int blockSize = cipher.getBlockSize();

            // We need to pad with zeros to a multiple of the cipher block size,
            // so first figure out what the size of the plaintext needs to be.
            byte[] dataBytes = data.getBytes();
            int plaintextLength = dataBytes.length;
            int remainder = plaintextLength % blockSize;
            if (remainder != 0) {
                plaintextLength += (blockSize - remainder);
            }

            // In java, primitive arrays of integer types have all elements
            // initialized to zero, so no need to explicitly zero any part of
            // the array.
            byte[] plaintext = new byte[plaintextLength];

            // Copy our actual data into the beginning of the array.  The
            // rest of the array is implicitly zero-filled, as desired.
            System.arraycopy(dataBytes, 0, plaintext, 0, dataBytes.length);

            SecretKeySpec keyspec = new SecretKeySpec(key.getBytes(), "AES");
            IvParameterSpec ivspec = new IvParameterSpec(iv.getBytes());

            cipher.init(Cipher.ENCRYPT_MODE, keyspec, ivspec);
            byte[] encrypted = cipher.doFinal(plaintext);

            return new sun.misc.BASE64Encoder().encode(encrypted);

        } catch (Exception e) {
            e.printStackTrace();
            return null;
        }
    }
}

当我跑步时,我得到:

iz1qFlQJfs6Ycp+gcc2z4w==

这是你的PHP程序得到的.

更新(2016年6月12日):从Java 8开始,JavaSE最终附带了一个记录的base64编解码器.而不是

return new sun.misc.BASE64Encoder().encode(encrypted);

你应该做点什么

return Base64.Encoder.encodeToString(encrypted);

或者,使用第三方库(例如commons-codec)进行base64编码/解码,而不是使用未记录的内部方法.