学步园

//加密  
function string2secret($str)  
{  
 $key = "123";  
 $td = mcrypt_module_open(MCRYPT_DES,'','ecb','');  
 $iv = mcrypt_create_iv(mcrypt_enc_get_iv_size($td), MCRYPT_RAND);  
 $ks = mcrypt_enc_get_key_size($td);  
  
 $key = substr(md5($key), 0, $ks);  
 mcrypt_generic_init($td, $key, $iv);  
 $secret = mcrypt_generic($td, $str);  
 mcrypt_generic_deinit($td);  
 mcrypt_module_close($td);  
 return $secret;  
}  
  
//解密  
function secret2string($sec)  
{  
 $key = "123";  
 $td = mcrypt_module_open(MCRYPT_DES,'','ecb','');  
 $iv = mcrypt_create_iv(mcrypt_enc_get_iv_size($td), MCRYPT_RAND);  
 $ks = mcrypt_enc_get_key_size($td);  
  
 $key = substr(md5($key), 0, $ks);  
 mcrypt_generic_init($td, $key, $iv);  
 $string = mdecrypt_generic($td, $sec);  
 mcrypt_generic_deinit($td);  
 mcrypt_module_close($td);  
 return trim($string);  
}  
  
echo secret2string(string2secret("11111111111111111"));   //显示结果是11111111111111111  
echo string2secret("11111111111111111");    //显示乱码 

//需要mcryp扩展的支持。