I just tried the below code on my local machine using the URL which you were using (seen from the logs) and I'm getting the results as intended:
$url = 'http://book.douban.com/subject/1044915/';
$c = curl_init();
$curl_header = array(
'User-Agent: Mozilla/4.0 (compatible; MSIE 7.0; Windows NT 6.1 )',
curl_setopt($c, CURLOPT_URL, $url);
curl_setopt($c, CURLOPT_CUSTOMREQUEST, 'GET');
curl_setopt($c, CURLOPT_RETURNTRANSFER, 1);
curl_setopt($c, CURLOPT_HTTPHEADER, $curl_header);
curl_setopt($c, CURLOPT_CONNECTTIMEOUT, 30);
curl_setopt($c, CURLOPT_TIMEOUT, 30);
curl_setopt($c, CURLOPT_HEADER, 0);
$res = curl_exec($c);
echo "<H1>HERE ARE THE RESULTS</H1>";
I still believe you are missing some piece of information in your piece of code that's causing the 403 response on your side.
Hope it helps.