【记录】华数视频地址加密方式算法PHP版本

此处仅作记录。

<?php
function streamCode($enstr, $token = "wasu!@#48217#$@#1") {
  $klen = 4;
  if (strstr($enstr,".mp4")) {
    return $enstr;
  }
  $token = md5($token);
  $tm = $_SERVER['REQUEST_TIME'];
  $key1 = md5(substr($token, 0, 16));
  $key2 = md5(substr($token, 16, 32));
  $key3 = substr($enstr, 0, $klen);
  $key4 = $key1.md5($key1.$key3);
  $keylen = strlen($key4);
  $enstr = base64_decode(substr($enstr, $klen));
  $l16 = 0;
  $l14 = array();
  $l15 = array();
  $local13 = strlen($enstr);
  while ($l16 < 128){
    $l14[$l16] = $l16;
    $l15[$l16] = ord(substr($key4, $l16 % $keylen, 1)) & 0xff;
    $l16++;
  }
  $l16 = 0;
  $l17 = $l16;
  while ($l16 < 128) {
    $l17 = (($l17 + $l14[$l16]) + $l15[$l16]) % 128;
    $l19 = $l14[$l16];
    $l14[$l16] = $l14[$l17];
    $l14[$l17] = $l19;
    $l16++;
  }
  $l16 = 0;
  $l20 = array();
  $l17 = $l16;
  $l18 = $l17;
  while ($l16 < $local13) {
    $l18 = (($l18 + 1) % 128);
    $l17 = (($l17 + $l14[$l18]) % 128);
    $l19 = $l14[$l18];
    $l14[$l18] = $l14[$l17];
    $l14[$l17] = $l19;
    $l20[] = ((ord(substr($enstr, $l16, 1)) & 0xFF) ^ $l14[(($l14[$l18] + $l14[$l17]) % 128)]);
    $l16++;
  }
  $toStr = "";
  for($i = 0; $i < count($l20); $i++){
    $toStr .= chr($l20[$i]);
  }
  return strlen($toStr) > 26 ? substr($toStr, 26) : "";
}

function get_WasuVODUrl($url) {
  $play = parse_url($url);
  $tm = $_SERVER['REQUEST_TIME'];
  $timestamp = date("YmdHi", $tm);
  $token = sprintf("%s%s%s", "ccVOD@)!#\$WASUPC", $timestamp, $play['path']);
  return sprintf("http://clientvod.wasu.cn/%s/%s%s", $timestamp, md5($token), $play['path']);
}

$url = "";
$link = isset($_REQUEST['url']) ? $_REQUEST['url'] : "";
$enstr = empty($_REQUEST['enstr']) ? "" : $_REQUEST['enstr'];
if (strlen($enstr) > 32) {
  $url = streamCode($enstr);
} else if (strlen($link) > 15) {
  $url = @get_WasuVODUrl(base64_decode($link));
}
echo '{"url":"'.$url.'"}';
?>