<?php/*** 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）**/class Descrypt{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 $ret;}}?>===================================================================================================================DEMO：<?phpheader('Content-Type:text/html;Charset=utf-8;');include('descrpty.php');echo '<pre>';//////////////////////////////////////$a = isset($_GET['a']) ? $_GET['a'] : 'zhangtao';//密钥//$key = '12345678123456781234567812345678'; //256 bit//$key = '1234567812345678'; //128 bit$key = '12345678'; //64 bit//设置模式和IV$m = new Descrypt($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>';?>
