1 define('KEY', '123456');
2 $data = 'oehpetyFTdYwZ3frZi1KkgtizgQs'; // 被加密信息
3 $encrypt = encrypt($data);
4 $decrypt = decrypt($encrypt);
5 echo $encrypt, "\n", $decrypt;
6 function decrypt($data) {
7 $key = md5(KEY);
8 $x = 0;
9 $data = base64_decode($data);
10 $len = strlen($data);
11 $l = strlen($key);
12 $char = $str = '';
13 for ($i = 0; $i < $len; $i++) {
14 if ($x == $l) {
15 $x = 0;
16 }
17 $char .= substr($key, $x, 1);
18 $x++;
19 }
20 for ($i = 0; $i < $len; $i++) {
21 if (ord(substr($data, $i, 1)) < ord(substr($char, $i, 1))) {
22 $str .= chr((ord(substr($data, $i, 1)) + 256) - ord(substr($char, $i, 1)));
23 } else {
24 $str .= chr(ord(substr($data, $i, 1)) - ord(substr($char, $i, 1)));
25 }
26 }
27 return $str;
28 }
29
30 function encrypt($data) {
31 $key = md5(KEY);
32 $x = 0;
33 $len = strlen($data);
34 $l = strlen($key);
35 $char = $str = '';
36 for ($i = 0; $i < $len; $i++) {
37 if ($x == $l) {
38 $x = 0;
39 }
40 $char .= $key{$x};
41 $x++;
42 }
43 for ($i = 0; $i < $len; $i++) {
44 $str .= chr(ord($data{$i}) + (ord($char{$i})) % 256);
45 }
46 return base64_encode($str);
47 }
