<?php
/*
 * Created on 2018-9-1
 *
 * To change the template for this generated file go to
 * Window - Preferences - PHPeclipse - PHP - Code Templates
 */
 /**
 用法：
 Security::encrypt($str,$key);
 Security::decrypt($str,$key);
 */
 class Security {
  public static function encrypt($input, $key) {
   $size = mcrypt_get_block_size(MCRYPT_RIJNDAEL_128, MCRYPT_MODE_ECB);
   $input = Security::pkcs5_pad($input, $size);
   $td = mcrypt_module_open(MCRYPT_RIJNDAEL_128, '', MCRYPT_MODE_ECB, '');
   $iv = mcrypt_create_iv (mcrypt_enc_get_iv_size($td), MCRYPT_RAND);
   mcrypt_generic_init($td, $key, $iv);
   $data = mcrypt_generic($td, $input);
   mcrypt_generic_deinit($td);
   mcrypt_module_close($td);
   $data = base64_encode($data);
   return $data;
  }
  private static function pkcs5_pad ($text, $blocksize) {
   $pad = $blocksize - (strlen($text) % $blocksize);
   return $text . str_repeat(chr($pad), $pad);
  }
  public static function decrypt($sStr, $sKey) {
   $decrypted= mcrypt_decrypt(
    MCRYPT_RIJNDAEL_128,
    $sKey,
    base64_decode($sStr),
    MCRYPT_MODE_ECB
   );
   $dec_s = strlen($decrypted);
   $padding = ord($decrypted[$dec_s-1]);
   $decrypted = substr($decrypted, 0, -$padding);
   return $decrypted;
  }
 }
//用法示例：
$str = "www.jb51.net";
$key = "123456";
echo "原始字符串：".$str."<br/>";
$pwdstr = Security::encrypt($str,$key);
echo "加密后：".$pwdstr."<br/>";
$destr = Security::decrypt($pwdstr,$key);
echo "解密结果：".$destr;
?>