PHP對稱加密算法（DES/AES）類
/**
- 常用對稱加密算法類
- 支持密鑰：64/128/256 bit（字節長度8/16/32）
- 支持算法：DES/AES（根據密鑰長度自動匹配使用：DES:64bit AES:128/256bit）
- 支持模式：CBC/ECB/OFB/CFB
- 密文編碼：base64字符串/十六進制字符串/二進制字符串流
- 填充方式: PKCS5Padding（DES）
- @author: linvo
- @version: 1.0.0
@date: 2013/1/10 */
class Xcrypt{private $mcrypt;
private $key;
private $mode;
private $iv;
private $blocksize;/**
- 構造函數
- @param string 密鑰
- @param string 模式
@param string 向量（"off":不使用 / "auto":自動 / 其他:指定值，長度同密鑰） */
public function __construct($key, $mode = 'cbc', $iv = "off"){
switch (strlen($key)){
case 8:$this->mcrypt = MCRYPT_DES; break;case 16:
$this->mcrypt = MCRYPT_RIJNDAEL_128; break;case 32:
$this->mcrypt = MCRYPT_RIJNDAEL_256; break;default:
die("Key size must be 8/16/32");}
$this->key = $key;
switch (strtolower($mode)){
case 'ofb':$this->mode = MCRYPT_MODE_OFB; if ($iv == 'off') die('OFB must give a IV'); //OFB必須有向量 break;case 'cfb':
$this->mode = MCRYPT_MODE_CFB; if ($iv == 'off') die('CFB must give a IV'); //CFB必須有向量 break;case 'ecb':
$this->mode = MCRYPT_MODE_ECB; $iv = 'off'; //ECB不需要向量 break;case 'cbc':
default:$this->mode = MCRYPT_MODE_CBC;}
switch (strtolower($iv)){
case "off":$this->iv = null; break;case "auto":
$source = PHP_OS=='WINNT' ? MCRYPT_RAND : MCRYPT_DEV_RANDOM; $this->iv = mcrypt_create_iv(mcrypt_get_block_size($this->mcrypt, $this->mode), $source); break;default:
$this->iv = $iv;}
}
/**
- 獲取向量值
- @param string 向量值編碼（base64/hex/bin）
@return string 向量值 */
public function getIV($code = 'base64'){
switch ($code){
case 'base64':$ret = base64_encode($this->iv); break;case 'hex':
$ret = bin2hex($this->iv); break;case 'bin':
default:$ret = $this->iv;}
return $ret;
}/**
- 加密
- @param string 明文
- @param string 密文編碼（base64/hex/bin）
@return string 密文 */
public function encrypt($str, $code = 'base64'){
if ($this->mcrypt == MCRYPT_DES) $str = $this->_pkcs5Pad($str);if (isset($this->iv)) {
$result = mcrypt_encrypt($this->mcrypt, $this->key, $str, $this->mode, $this->iv);} else {
@$result = mcrypt_encrypt($this->mcrypt, $this->key, $str, $this->mode);}
switch ($code){
case 'base64':$ret = base64_encode($result); break;case 'hex':
$ret = bin2hex($result); break;case 'bin':
default:$ret = $result;}
return $ret;
}
/**
- 解密
- @param string 密文
- @param string 密文編碼（base64/hex/bin）
@return string 明文 */
public function decrypt($str, $code = "base64"){
$ret = false;switch ($code){
case 'base64':$str = base64_decode($str); break;case 'hex':
$str = $this->_hex2bin($str); break;case 'bin':
default:
}if ($str !== false){
if (isset($this->iv)) { $ret = mcrypt_decrypt($this->mcrypt, $this->key, $str, $this->mode, $this->iv); } else { @$ret = mcrypt_decrypt($this->mcrypt, $this->key, $str, $this->mode); } if ($this->mcrypt == MCRYPT_DES) $ret = $this->_pkcs5Unpad($ret);}
return $ret;
}private function _pkcs5Pad($text){
$this->blocksize = mcrypt_get_block_size($this->mcrypt, $this->mode);
$pad = $this->blocksize - (strlen($text) % $this->blocksize);
return $text . str_repeat(chr($pad), $pad);
}private function _pkcs5Unpad($text){
$pad = ord($text{strlen($text) - 1});
if ($pad > strlen($text)) return false;
if (strspn($text, chr($pad), strlen($text) - $pad) != $pad) return false;
$ret = substr($text, 0, -1 * $pad);
return $ret;
}private function _hex2bin($hex = false){
$ret = $hex !== false && preg_match('/^[0-9a-fA-F]+$/i', $hex) ? pack("H*", $hex) : false;
return $ret;
}
}
</pre>
使用示例：
<?php
header('Content-Type:text/html;Charset=utf-8;');include "xcrypt.php";
echo '<pre>';
//////////////////////////////////////
$a = isset($_GET['a']) ? $_GET['a'] : '測試123';//密鑰
$key = '12345678123456781234567812345678'; //256 bit
$key = '1234567812345678'; //128 bit
$key = '12345678'; //64 bit//設置模式和IV
$m = new Xcrypt($key, 'cbc', 'auto');//獲取向量值
echo '向量：';
var_dump($m->getIV());//加密
$b = $m->encrypt($a, 'base64');
//解密
$c = $m->decrypt($b, 'base64');echo '加密后：';
var_dump($b);
echo '解密后：';
var_dump($c);/////////////////////////////////////////
echo '</pre>'; </pre>