很多时候我们需要对数据进行加密解密,比如有些数据需要保存到cookie中,但又不能被用户轻易得到这些数据,这时我们就需要加密这些数据保存到cookie中,等我们需要使用它们的时候再解密。
加密的过程如下:
折叠展开PHP 代码
-
- $cookie_data = $this -> encrypt("nowamagic", $data);
- $cookie = array(
- 'name' => '$data',
- 'value' => $cookie_data,
- 'expire' => $user_expire,
- 'domain' => '',
- 'path' => '/',
- 'prefix' => ''
- );
- $this->input->set_cookie($cookie);
-
- public function encrypt($key, $plain_text) {
- $plain_text = trim($plain_text);
- $iv = substr(md5($key), 0,mcrypt_get_iv_size (MCRYPT_CAST_256,MCRYPT_MODE_CFB));
- $c_t = mcrypt_cfb (MCRYPT_CAST_256, $key, $plain_text, MCRYPT_ENCRYPT, $iv);
- return trim(chop(base64_encode($c_t)));
- }
使用的时候再解密:
折叠展开PHP 代码
- if( isset($_COOKIE['data']) ){
-
- $_SESSION['data'] = decrypt("nowamagic", $_COOKIE['data']);
- }
- function decrypt($key, $c_t) {
- $c_t = trim(chop(base64_decode($c_t)));
- $iv = substr(md5($key), 0,mcrypt_get_iv_size (MCRYPT_CAST_256,MCRYPT_MODE_CFB));
- $p_t = mcrypt_cfb (MCRYPT_CAST_256, $key, $c_t, MCRYPT_DECRYPT, $iv);
- return trim(chop($p_t));
- }