/** * 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); } 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; } } 使用示例：
<?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>';
