php实现AES/CBC/PKCS5Padding加密解密（又叫：对称加密）

配合java程序接口的架接，java那边需要我这边对传过去的值进行AES对称加密，接口返回的结果也是加密过的（就要用到解密），然后试了很多办法，也一一对应了AES的key密钥值，偏移量（IV）的值，都还是不能和java加密解密的结果一样。接着我就去找了一些文档，结果发现PHP里面补码方式只有：ZeroPadding这一种方式，而java接口那边是用PKCS5Padding补码方式，发现了问题所在，就编写了如下PHP实现AES/CBC/PKCS5Padding的加密解密方式。如有错误，还请指正！
对接农业银行接口的数据加密

class MagicCrypt {
    private $iv = "9457e5f423704b15";//密钥偏移量IV，可自定义
    private $encryptKey = "cff054d1d7c84036a3dc160f";//AESkey，可自定义

    //加密
    public function encrypt($encryptStr) {
        $localIV = $this->iv;
        $encryptKey = $this->encryptKey;

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

        //print "module = $module <br/>" ;

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

        //Padding
        $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

        //encrypt
        $encrypted = @mcrypt_generic($module, $encryptStr);

        //Close
        @mcrypt_generic_deinit($module);
        @mcrypt_module_close($module);

        return base64_encode($encrypted);

    }

    //解密
    public function decrypt($encryptStr) {
        $localIV = $this->iv;
        $encryptKey = $this->encryptKey;

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

        //print "module = $module <br/>" ;

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

        $encryptedData = base64_decode($encryptStr);
        $encryptedData = @mdecrypt_generic($module, $encryptedData);
        //去补码,缺少这个PHP解密后面会有问号乱码
        $pad = ord($encryptedData{strlen($encryptedData) - 1});
        if ($pad > strlen($encryptedData)) {
            return false;
        }
        return substr($encryptedData, 0, -1 * $pad);
    }
}

参考https://www.cnblogs.com/lonmyblog/p/7885974.html