我正在尝试从非 Apple 设备加载以下资源：
http://a1285.phobos.apple.com/us/r30/Music/e2/62/81/mzm.fiyyuoea.aac.p.m4a
该 URL 由 iTunes 搜索 API 提供。它在 iPhone 浏览器上运行良好，但我的 Linux Chrome 浏览器收到 403 Forbidden 响应。
我试图用 Curl 欺骗 User-Agent 标头：
curl -v -A 'Mozilla/5.0 (iPhone; U; CPU iPhone OS 3_0 like Mac OS X; en-us) AppleWebKit/528.18 (KHTML, like Gecko) Version/4.0 Mobile/7A341 Safari/528.16' http://a1285.phobos.apple.com/us/r30/Music/e2/62/81/mzm.fiyyuoea.aac.p.m4a
但我仍然得到 403 Forbidden。这个文件可以在 iPhone 浏览器上正常播放。Apple 如何知道在不查看 User-Agent 标头的情况下阻止我的设备？
编辑：
这是可以加载资源的机器的 curl 输出：
curl -vI http://a1285.phobos.apple.com/us/r30/Music/e2/62/81/mzm.fiyyuoea.aac.p.m4a
* About to connect() to a1285.phobos.apple.com port 80 (#0)
* Trying 23.67.251.59... connected
* Connected to a1285.phobos.apple.com (23.67.251.59) port 80 (#0)
> HEAD /us/r30/Music/e2/62/81/mzm.fiyyuoea.aac.p.m4a HTTP/1.1
> User-Agent: curl/7.21.4 (universal-apple-darwin11.0) libcurl/7.21.4 OpenSSL/0.9.8r zlib/1.2.5
> Host: a1285.phobos.apple.com
> Accept: */*
>
< HTTP/1.1 200 OK
HTTP/1.1 200 OK
< Server: Apache
Server: Apache
< Last-Modified: Wed, 12 Sep 2012 07:32:54 GMT
Last-Modified: Wed, 12 Sep 2012 07:32:54 GMT
< ETag: "ff7b1-4c97c32e92716"
ETag: "ff7b1-4c97c32e92716"
< Accept-Ranges: bytes
Accept-Ranges: bytes
< Content-Length: 1046449
Content-Length: 1046449
< X-Server: nk11p00it-web038
X-Server: nk11p00it-web038
< Date: Sun, 21 Jul 2013 07:50:18 GMT
Date: Sun, 21 Jul 2013 07:50:18 GMT
< Connection: keep-alive
Connection: keep-alive
< Content-Type: audio/mp4
Content-Type: audio/mp4
<
* Connection #0 to host a1285.phobos.apple.com left intact
* Closing connection #0
这是我的机器无法加载资源的 curl 输出：
curl -vI http://a1285.phobos.apple.com/us/r30/Music/e2/62/81/mzm.fiyyuoea.aac.p.m4a
* About to connect() to a1285.phobos.apple.com port 80 (#0)
* Trying 124.40.233.83...
* connected
* Connected to a1285.phobos.apple.com (124.40.233.83) port 80 (#0)
> HEAD /us/r30/Music/e2/62/81/mzm.fiyyuoea.aac.p.m4a HTTP/1.1
> User-Agent: curl/7.27.0
> Host: a1285.phobos.apple.com
> Accept: */*
>
* additional stuff not fine transfer.c:1037: 0 0
* HTTP 1.1 or later with persistent connection, pipelining supported
< HTTP/1.1 403 Forbidden
HTTP/1.1 403 Forbidden
< Server: AkamaiGHost
Server: AkamaiGHost
< Mime-Version: 1.0
Mime-Version: 1.0
< Content-Length: 359
Content-Length: 359
< Expires: Sun, 21 Jul 2013 07:56:14 GMT
Expires: Sun, 21 Jul 2013 07:56:14 GMT
< Date: Sun, 21 Jul 2013 07:56:14 GMT
Date: Sun, 21 Jul 2013 07:56:14 GMT
< Connection: keep-alive
Connection: keep-alive
< Content-Type: audio/mp4
Content-Type: audio/mp4
<
* Connection #0 to host a1285.phobos.apple.com left intact
* Closing connection #0