PHP 中的 256 位 AES 解密

Question

我在 Java 中有一个工作示例，如何使用密钥解密（256 位 AES）字符串。我需要在 PHP 中复制解密算法，并且几乎可以使用它。

这是用 Java 解密的消息：

CSM(MCL/KEX RCV/10001031 ORG/Comdata KYN/dsNAX6hFtKvfceT KEY/C062E276949D83554D7B5198C52C4C55ED1C65370FA71F8220538A0C3BA23172)

然而，当我调用它给出的 PHP 方法时

10001031 ORG/Comdata KYN/dsNAX6hFtKvfceT KEY/C062E276949D83554D7B5198C52C4C55ED1C65370FA71F8220538A0C3BA23172)

正如您所见，它并不遥远，但 PHP 方法不会返回前 17 个字符（即“CSM（MCL/KEX RCV/”位）。

我在这里错过了一些琐碎的事情吗？

这是 PHP 类：

class OpensslAES
{
    const METHOD = 'aes-256-cbc';

    public static function encrypt($message, $key)
    {
        if (mb_strlen($key, '8bit') !== 32) {
            throw new Exception("Needs a 256-bit key!");
        }
        $ivsize = openssl_cipher_iv_length(self::METHOD);
        $iv = openssl_random_pseudo_bytes($ivsize);

        $ciphertext = openssl_encrypt(
            $message,
            self::METHOD,
            $key,
            OPENSSL_RAW_DATA,
            $iv
        );

        return $iv.$ciphertext;
    }

    public static function decrypt($message, $key)
    {
        if (mb_strlen($key, '8bit') !== 32) {
            throw new Exception("Needs a 256-bit key!");
        }
        $ivsize = openssl_cipher_iv_length(self::METHOD);
        $iv = mb_substr($message, 0, $ivsize, '8bit');
        $ciphertext = mb_substr($message, $ivsize, null, '8bit');

        return openssl_decrypt(
            $ciphertext,
            self::METHOD,
            $key,
            OPENSSL_RAW_DATA,
            $iv
        );
    }
}

$class = new OpensslAES();

var_dump($class->decrypt(base64_decode("cBVlMjBttr7DKW8fhHtqJOLyMBNrgxpIJsgFFPjkA/4MWxMIudOnYzS4WuxIhUjtgGgk4CzrkJ1G60R4OWBljNTMA9ATPKh9PXe7wXAwJfE9zc698bQv4lDkXRME+q4xCb3bK/UGQ/BPVIkmRYdHcBvIHXNzGd36Nn40giigY/g="), hex2bin("SECRET_KEY_GOES_HERE")));

这是 Java 类：

package javaapplication1;

import org.apache.commons.codec.binary.Base64;
import org.apache.commons.codec.binary.StringUtils;
import org.apache.commons.codec.binary.Hex;

import java.security.InvalidAlgorithmParameterException;
import java.security.InvalidKeyException;
import java.security.NoSuchAlgorithmException;
import java.security.SecureRandom;

import javax.crypto.BadPaddingException;
import javax.crypto.Cipher;
import javax.crypto.IllegalBlockSizeException;
import javax.crypto.KeyGenerator;
import javax.crypto.NoSuchPaddingException;
import javax.crypto.SecretKey;
import javax.crypto.spec.IvParameterSpec;
import javax.crypto.spec.SecretKeySpec;

import javax.xml.bind.DatatypeConverter;

public class JavaApplication1 {

    public static void main(String[] args) {
        byte[] ENCRYPTION_KEY = JavaApplication1.toByteArray("SECRET_KEY_GOES_HERE");
        String INPUT = new String("cBVlMjBttr7DKW8fhHtqJOLyMBNrgxpIJsgFFPjkA/4MWxMIudOnYzS4WuxIhUjtgGgk4CzrkJ1G60R4OWBljNTMA9ATPKh9PXe7wXAwJfE9zc698bQv4lDkXRME+q4xCb3bK/UGQ/BPVIkmRYdHcBvIHXNzGd36Nn40giigY/g=");

        try {
            System.out.println(JavaApplication1.decryptStringAES(INPUT, ENCRYPTION_KEY));
        } catch (Exception exception) {
            System.out.println("Error occured: " + exception);
        }
    }

    public static byte[] toByteArray(String s) {
        return DatatypeConverter.parseHexBinary(s);
    }

    public static String decryptStringAES(String input, byte[] key) throws Exception {
        byte[] IV = JavaApplication1.toByteArray("00000000000000000000000000000000");

        byte[] inputBytes = Base64.decodeBase64(input.getBytes());
        Cipher decryptCipher = Cipher.getInstance("AES/CBC/PKCS5Padding");
        decryptCipher.init(Cipher.DECRYPT_MODE, new SecretKeySpec(key, "AES"), new
        IvParameterSpec(IV));
        byte[] decrypt = decryptCipher.doFinal(inputBytes);
        return new String(decrypt);
    }
}

Answer 1

您的 Java 实现期望 IV 始终为零，而您的 PHP 实现期望 IV 被添加到消息的前面。

如果您希望您的 PHP 实现与您的 Java 代码兼容，那么您可以像这样进行更改：

class OpensslAES
{
    const METHOD = 'aes-256-cbc';

    public static function encrypt($message, $key)
    {
        if (mb_strlen($key, '8bit') !== 32) {
            throw new Exception("Needs a 256-bit key!");
        }
        $ivsize = openssl_cipher_iv_length(self::METHOD);
        $iv = hex2bin('00000000000000000000000000000000');

        return openssl_encrypt(
            $message,
            self::METHOD,
            $key,
            OPENSSL_RAW_DATA,
            $iv
        );
    }

    public static function decrypt($message, $key)
    {
        if (mb_strlen($key, '8bit') !== 32) {
            throw new Exception("Needs a 256-bit key!");
        }
        $ivsize = openssl_cipher_iv_length(self::METHOD);
        $iv = hex2bin('00000000000000000000000000000000');

        return openssl_decrypt(
            $message,
            self::METHOD,
            $key,
            OPENSSL_RAW_DATA,
            $iv
        );
    }
}

$class = new OpensslAES();

var_dump($class->decrypt(base64_decode("cBVlMjBttr7DKW8fhHtqJOLyMBNrgxpIJsgFFPjkA/4MWxMIudOnYzS4WuxIhUjtgGgk4CzrkJ1G60R4OWBljNTMA9ATPKh9PXe7wXAwJfE9zc698bQv4lDkXRME+q4xCb3bK/UGQ/BPVIkmRYdHcBvIHXNzGd36Nn40giigY/g="), hex2bin("SECRET_KEY_GOES_HERE")));