php 3des加密解密是一个在数据传输中常用的一个简单的加密方式了,下面我整理了一个php 3des加密解密类程序有需要了解的朋友可进入参考.

3DES(或称为Triple DES)是三重数据加密算法(TDEA,Triple Data Encryption Algorithm)块密码的通称,它相当于是对每个数据块应用三次DES加密算法,由于计算机运算能力的增强,原版DES密码的密钥长度变得容易被暴力破解,3DES即是设计用来提供一种相对简单的方法,即通过增加DES的密钥长度来避免类似的攻击,而不是设计一种全新的块密码算法.

php 3des加密解密类程序代码如下:

1. <?php
2. class Crypt3Des {
3. var $key;
4. function Crypt3Des($key){
5. $this->key = $key;
6. }
7. function encrypt($input){
8. $size = mcrypt_get_block_size(MCRYPT_3DES,'ecb');
9. $input = $this->pkcs5_pad($input, $size);
10. $key = str_pad($this->key,24,'0');
11. $td = mcrypt_module_open(MCRYPT_3DES, '', 'ecb', '');
12. $iv = @mcrypt_create_iv (mcrypt_enc_get_iv_size($td), MCRYPT_RAND);
13. @mcrypt_generic_init($td, $key, $iv);
14. $data = mcrypt_generic($td, $input);
15. mcrypt_generic_deinit($td);
16. mcrypt_module_close($td);
17. //$data = base64_encode($this->PaddingPKCS7($data));
18. $data = base64_encode($data);
19. return $data;
20. }
21. function decrypt($encrypted){
22. $encrypted = base64_decode($encrypted);
23. $key = str_pad($this->key,24,'0');
24. $td = mcrypt_module_open(MCRYPT_3DES,'','ecb','');
25. $iv = @mcrypt_create_iv(mcrypt_enc_get_iv_size($td),MCRYPT_RAND);
26. $ks = mcrypt_enc_get_key_size($td);
27. @mcrypt_generic_init($td, $key, $iv);
28. $decrypted = mdecrypt_generic($td, $encrypted);
29. mcrypt_generic_deinit($td);
30. mcrypt_module_close($td);
31. $y=$this->pkcs5_unpad($decrypted);
32. return $y;
33. }
34. function pkcs5_pad ($text, $blocksize) {
35. $pad = $blocksize - (strlen($text) % $blocksize);
36. return $text . str_repeat(chr($pad), $pad);
37. }
38. function pkcs5_unpad($text){
39. $pad = ord($text{strlen($text)-1});
40. if ($pad > strlen($text)) {
41. return false;
42. }
43. if (strspn($text, chr($pad), strlen($text) - $pad) != $pad){
44. return false;
45. }
46. return substr($text, 0, -1 * $pad);
47. }
48. //开源代码phpfensi.com
49. function PaddingPKCS7($data) {
50. $block_size = mcrypt_get_block_size(MCRYPT_3DES, MCRYPT_MODE_CBC);
51. $padding_char = $block_size - (strlen($data) % $block_size);
52. $data .= str_repeat(chr($padding_char),$padding_char);
53. return $data;
54. }
55. }
56. ?>

用法:

$crypt = new Crypt3Des('密钥');

$a = '待加密字符串';

$code = $crypt->encrypt($a);//加密

echo $crypt->decrypt($code);//解密