/**
* 常用对称加密算法类
* 支持密钥：64/128/256 bit（字节长度8/16/32）
* 支持算法：DES/AES（根据密钥长度自动匹配使用：DES:64bit AES:128/256bit）
* 支持模式：CBC/ECB/OFB/CFB
* 密文编码：base64字符串/十六进制字符串/二进制字符串流
* 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 $blocksize; ?
?
???/**
????* 构造函数
????*
????* @param string 密钥
????* @param string 模式
????* @param string 向量（"off":不使用 / "auto":自动 / 其他:指定值，长度同密钥）
????*/ ?
???public function __construct($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必须有向量 ?
???????????break; ?
???????case ‘cfb‘: ?
???????????$this->mode = MCRYPT_MODE_CFB; ?
???????????if ($iv == ‘off‘) die(‘CFB must give a IV‘); //CFB必须有向量 ?
???????????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 = $iv; ?
???????} ?
?
????
???} ?
?
?
???/**
????* 获取向量值
????* @param string 向量值编码（base64/hex/bin）
????* @return string 向量值
????*/ ?
???public function getIV($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 $ret; ?
???} ?
?
?
???/**
????* 加密
????* @param string 明文
????* @param string 密文编码（base64/hex/bin）
????* @return string 密文
????*/ ?
???public function encrypt($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 $ret; ?
??
???} ?
?
???/**
????* 解密 ?
????* @param string 密文
????* @param string 密文编码（base64/hex/bin）
????* @return string 明文
????*/ ?
???public function decrypt($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); ?
???????????$ret = trim($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; ?
???} ?
?
?
?
}
<?php
header(‘Content-Type:text/html;Charset=utf-8;‘); ?
?
include "xcrypt.php"; ?
?
echo ‘<pre>‘; ?
////////////////////////////////////// ?
$a = isset($_GET[‘a‘]) ? $_GET[‘a‘] : ‘测试123‘; ?
?
//密钥 ?
$key = ‘12345678123456781234567812345678‘; //256 bit ?
$key = ‘1234567812345678‘; //128 bit ?
$key = ‘12345678‘; //64 bit ?
?
//设置模式和IV ?
$m = new Xcrypt($key, ‘cbc‘, ‘auto‘); ?
?
//获取向量值 ?
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>‘;
对称加密php
原文地址：http://www.cnblogs.com/jackbo/p/7504159.html