php加密解密处理类--参 考：Discuz论坛的passpor

<?php

02	/*===========================================================

03

= 版权协议：

04	= GPL (The GNU GENERAL PUBLIC LICENSE Version 2, June 1991)

05	=------------------------------------------------------------

06	= 文件名称：cls.sys_crypt.php

07	= 摘    要：php加密解密处理类

08	= 版    本：1.0

09	= 参    考：Discuz论坛的passport相关函数

10	=------------------------------------------------------------

11	= Script Written By PHPWMS项目组

12	= 最后更新：xinge

13	= 最后日期：2007-12-09

14	============================================================*/

15

16	class SysCrypt {

17

18	private $crypt_key;

19

20

// 构造函数

21	public function __construct($crypt_key) {

22	$this -> crypt_key = $crypt_key;

23

}

24

25	public function php_encrypt($txt) {

26	srand((double)microtime() * 1000000);

27	$encrypt_key = md5(rand(0,32000));

28

$ctr = 0;

29	$tmp = '';

30	for($i = 0;$i<code class="php functions">strlen($txt);$i++) {

31	$ctr = $ctr == <code class="php functions">strlen($encrypt_key) ? 0 : $ctr;

32	$tmp .= $encrypt_key[$ctr].($txt[$i]^$encrypt_key[$ctr++]);

33

}

34	return base64_encode(self::__key($tmp,$this -> crypt_key));

35

}

36

37	public function php_decrypt($txt) {

38	$txt = self::__key(base64_decode($txt),$this -> crypt_key);

39	$tmp = '';

40	for($i = 0;$i <code class="php functions">strlen($txt); $i++) {

41	$md5 = $txt[$i];

42	$tmp .= $txt[++$i] ^ $md5;

43

}

44	return $tmp;

45

}

46

47	private function __key($txt,$encrypt_key) {

48	$encrypt_key = md5($encrypt_key);

49

$ctr = 0;

50	$tmp = '';

51	for($i = 0; $i <code class="php functions">strlen($txt); $i++) {

52	$ctr = $ctr == <code class="php functions">strlen($encrypt_key) ? 0 : $ctr;

53	$tmp .= $txt[$i] ^ $encrypt_key[$ctr++];

54

}

55	return $tmp;

56

}

57

58	public function __destruct() {

59	$this -> crypt_key = null;

60

}

61

}

62

63

64	$sc = new SysCrypt('phpwms');

65	$text = '110';

66	print($sc -> php_encrypt($text));

67	print('<br>');

68	print($sc -> php_decrypt($sc -> php_encrypt($text)));

69

?>