PHP模拟百度URL加密解密算法

    PHP模拟百度URL加密解密算法的代码如下

    <?php
    $time = time() . rand(1000, 9999);
    $data = "{$time}###https://www.lseventt.com"; // 被加密信息
    $key = '123'; // 密钥
    $encrypt = encrypt($data, $key);
    $decrypt = decrypt($encrypt, $key);
    echo $encrypt, "\n", $decrypt;
    function encrypt($data, $key) {
        $key = md5($key);
        $x = 0;
        $len = strlen($data);
        $l = strlen($key);
        for ($i = 0; $i < $len; $i++) {
            if ($x == $l) {
                $x = 0;
            }
            $char.= $key{$x};
            $x++;
        }
        for ($i = 0; $i < $len; $i++) {
            $str.= chr(ord($data{$i}) + (ord($char{$i})) % 256);
        }
        return base64_encode($str);
    }
    function decrypt($data, $key) {
        $key = md5($key);
        $x = 0;
        $data = base64_decode($data);
        $len = strlen($data);
        $l = strlen($key);
        for ($i = 0; $i < $len; $i++) {
            if ($x == $l) {
                $x = 0;
            }
            $char.= substr($key, $x, 1);
            $x++;
        }
        for ($i = 0; $i < $len; $i++) {
            if (ord(substr($data, $i, 1)) < ord(substr($char, $i, 1))) {
                $str.= chr((ord(substr($data, $i, 1)) + 256) - ord(substr($char, $i, 1)));
            } else {
                $str.= chr(ord(substr($data, $i, 1)) - ord(substr($char, $i, 1)));
            }
        }
        return $str;
    }