[李景山php]每天laravel-20160829|McryptEncrypter-3

    /**     * Run the mcrypt decryption routine for the value.     *     * @param  string  $value     * @param  string  $iv     * @return string     *     * @throws \Illuminate\Contracts\Encryption\DecryptException     */    protected function mcryptDecrypt($value, $iv)    {        try {            return mcrypt_decrypt($this->cipher, $this->key, $value, MCRYPT_MODE_CBC, $iv);        } catch (Exception $e) {            throw new DecryptException($e->getMessage());        }    }//run function to decryption routine    // this is a wrap about the mcrypt_decrypt    /**     * Add PKCS7 padding to a given value.     *     * @param  string  $value     * @return string     */    protected function addPadding($value)    {        $pad = $this->block - (strlen($value) % $this->block);// this is a number        return $value.str_repeat(chr($pad), $pad);// get this wale repeat this    }// bad pad function    /**     * Remove the padding from the given value.     *     * @param  string  $value     * @return string     */    protected function stripPadding($value)    {        $pad = ord($value[($len = strlen($value)) - 1]);        return $this->paddingIsValid($pad, $value) ? substr($value, 0, $len - $pad) : $value;    }// remove the padding from the given value.    // check this value    /**     * Determine if the given padding for a value is valid.     *     * @param  string  $pad     * @param  string  $value     * @return bool     */    protected function paddingIsValid($pad, $value)    {        $beforePad = strlen($value) - $pad;        return substr($value, $beforePad) == str_repeat(substr($value, -1), $pad);    }// check pad valid    /**     * Get the IV size for the cipher.     *     * @return int     */    protected function getIvSize()    {        return mcrypt_get_iv_size($this->cipher, MCRYPT_MODE_CBC);    }// get the iv size    /**     * Get the random data source available for the OS.     *     * @return int     */    protected function getRandomizer()// get the random    {        if (defined('MCRYPT_DEV_URANDOM')) {            return MCRYPT_DEV_URANDOM;        }        if (defined('MCRYPT_DEV_RANDOM')) {            return MCRYPT_DEV_RANDOM;        }        mt_srand();        return MCRYPT_RAND;    }}