- /**
- * Commonly used symmetric encryption algorithms
- * Supported keys: 64/128/256 bit (byte length 8/16/32)
- * Supported algorithms: DES/AES (automatically matched according to key length: DES: 64bit AES :128/256bit)
- * Supported modes: CBC/ECB/OFB/CFB
- * Ciphertext encoding: base64 string/hex string/binary string stream
- * Padding method: PKCS5Padding (DES)
- *
- * @author: linvo
- * @version: 1.0.0
- * @date: 2013/1/10
- */
- class Xcrypt{
-
- private $mcrypt;
- private $key;
- private $mode;
- private $iv;
- private $blocksize;
-
- /**
- * Constructor
- *
- * @param string key
- * @param string mode
- * @param string vector ("off": not used / "auto": automatic / other: specified value, the same length as the key)
- */
- public function __construct($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 = $iv;
- }
-
-
- }
-
-
- /**
- * Get vector value
- * @param string vector value encoding (base64/hex/bin)
- * @return string vector value
- */
- public function getIV($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 $ret;
- }
-
-
- /**
- * Encryption
- * @param string plain text
- * @param string cipher text encoding (base64/hex/bin)
- * @return string cipher text
- */
- public function encrypt($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 $ret;
-
- }
-
- /**
- * Decryption
- * @param string ciphertext
- * @param string ciphertext encoding (base64/hex/bin)
- * @return string plaintext
- */
- public function decrypt($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 $ret;
- }
-
-
-
- }
-
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使用示例:
- header('Content-Type:text/html;Charset=utf-8;');
-
- include "xcrypt.php";
-
- echo '
'; </li>
<li>////////////////////////////////////// </li>
<li>$a = isset($_GET['a']) ? $_GET['a'] : '测试123'; </li>
<li> </li>
<li>//密钥 </li>
<li>$key = '12345678123456781234567812345678'; //256 bit </li>
<li>$key = '1234567812345678'; //128 bit </li>
<li>$key = '12345678'; //64 bit </li>
<li> </li>
<li>//设置模式和IV </li>
<li>$m = new Xcrypt($key, 'cbc', 'auto'); </li>
<li> </li>
<li>//获取向量值 </li>
<li>echo '向量:'; </li>
<li>var_dump($m->getIV()); </li>
<li> </li>
<li>//加密 </li>
<li>$b = $m->encrypt($a, 'base64'); </li>
<li>//解密 </li>
<li>$c = $m->decrypt($b, 'base64'); </li>
<li> </li>
<li>echo '加密后:'; </li>
<li>var_dump($b); </li>
<li>echo '解密后:'; </li>
<li>var_dump($c); </li>
<li> </li>
<li> </li>
<li>///////////////////////////////////////// </li>
<li>echo ' ';
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