[PHP知识库]PHP对称加密解密AES/CBC/PKCS5Padding与JAVA互通

php实现AES/CBC/PKCS5Padding加密解密与java代码运行等到结果一致，php版本为5.6。期间尝试过很多方法得到的加密解密结果都与java的不一致，最后写出以下方法，亲测有效，主要原因就是php的填充方式一定要选对。

两种语言的密钥和偏移量需要一致。

java代码：

 private static final String KEY_ALGORITHM = "AES";
  private static String CHARSET_ENCODING = "UTF-8";
  private static final String CIPHER_ALGORITHM_CBC = "AES/CBC/PKCS5Padding";
  private String key;//密钥
  private String iv;//偏移量

  public AESCrypt(String appSecret)
    throws Exception
  {
    Utilities.isNotNull(appSecret, "appSecret");
    if (appSecret.length() != 40) {
      throw new Exception("appSecret长度不正确");
    }
    this.key = appSecret.substring(0, 24);
    this.iv = appSecret.substring(24);
  }
//AES加密
  public String enAESCrypt(String sSrc)
    throws Exception
  {
	  Exception ex1;
    try
    {
      Cipher cipher = Cipher.getInstance("AES/CBC/PKCS5Padding");
      byte[] raw = this.key.getBytes();
      SecretKeySpec skeySpec = new SecretKeySpec(raw, "AES");
      IvParameterSpec iv = new IvParameterSpec(this.iv.getBytes());

      cipher.init(1, skeySpec, iv);
      byte[] encrypted = cipher.doFinal(sSrc.getBytes(CHARSET_ENCODING));

      return Base64.encodeBase64String(encrypted);
    } catch (Exception ex) {
      ex.printStackTrace();
      ex1=ex;
      
    }throw new Exception("加密异常:" + ex1.getMessage());
  }

//AES加密
  public String deAESCrypt(String sSrc)
    throws Exception
  {
	  Exception ex1;
    try
    {
      byte[] raw = this.key.getBytes("ASCII");
      SecretKeySpec skeySpec = new SecretKeySpec(raw, "AES");
      Cipher cipher = Cipher.getInstance("AES/CBC/PKCS5Padding");
      IvParameterSpec iv = new IvParameterSpec(this.iv.getBytes());
      cipher.init(2, skeySpec, iv);
      byte[] encrypted = Base64.decodeBase64(sSrc);

      byte[] original = cipher.doFinal(encrypted);
      return new String(original, CHARSET_ENCODING);
    } catch (Exception ex) {
      ex.printStackTrace();
      ex1=ex;
    }throw new Exception("解密异常:" + ex1.getMessage());
  }

php版：

 //AES加密
    private function encrypt($encryptStr, $encryptKey,$localIV) {

        $module = mcrypt_module_open(MCRYPT_RIJNDAEL_128, '', MCRYPT_MODE_CBC, $localIV);

        mcrypt_generic_init($module, $encryptKey, $localIV);

        $block = mcrypt_get_block_size(MCRYPT_RIJNDAEL_128, MCRYPT_MODE_CBC);
        $pad = $block - (strlen($encryptStr) % $block); //Compute how many characters need to pad
        $encryptStr .= str_repeat(chr($pad), $pad); // After pad, the str length must be equal to block or its integer multiples

        $encrypted = mcrypt_generic($module, $encryptStr);

        mcrypt_generic_deinit($module);
        mcrypt_module_close($module);
        return base64_encode($encrypted);

    }

    //AES解密
    function decrypt($code,$key,$iv) {

        $td = mcrypt_module_open(MCRYPT_RIJNDAEL_128, '', MCRYPT_MODE_CBC, '');

        mcrypt_generic_init($td, $key, $iv);

        $str = mdecrypt_generic($td, base64_decode($code));

        mcrypt_get_block_size(MCRYPT_RIJNDAEL_128, MCRYPT_MODE_CBC);

        mcrypt_generic_deinit($td);

        mcrypt_module_close($td);

        return $this->strippadding($str);

    }

    private function strippadding($string) {

        $slast = ord(substr($string, -1));

        $slastc = chr($slast);

        $pcheck = substr($string, -$slast);

        if (preg_match("/$slastc{" . $slast . "}/", $string)) {

            $string = substr($string, 0, strlen($string) - $slast);

            return $string;

        } else {

            return false;

        }

    }