How to use use file_get_contents() with the requester's IP?

[HaLo2FrEeEk]

I want to get a remote webpage using file_get_contents(), but I want to get the file using the IP of the person running the script, not the server's IP. Right now the file will be retrieved just fine but it uses my server's IP to do so. Requesting the page generates a unique key that is associated with the IP address, but I want my users to be able to download urls that I parse from the webpage (they contain the unique key). The only way I can think to do this is the somehow make the request as though it were from the running user's IP address. Is something like this possible, perhaps using a stream context? I tried but I just don't know enough about contexts, and Google / php.net is not helping.

[JKing]

What you are asking for sounds like IP spoofing to me.

[HaLo2FrEeEk]

You could think of it like that, but it's not.

It's a Youtube downloader. You put in the video ID and it gets the download URLs for all available resolutions. The URLs contain a key unique to the requesting IP. Since my server is doing the request, the key is matched to my server's IP. If I could have my server make the request but do so as though the request were coming from the running user's IP, then the IP would be matched to the user's IP and thus they would be able to download it directly.

[JKing]

If I could have my server make the request but do so as though the request were coming from the running user's IP

That's pretty much the definition of spoofing to me. I understand you have no malicious intent but I don't think this is the right way to achieve what you are trying to do.

What is the site you are trying to interface with? Do they have an API? Have you contacted them?

[HaLo2FrEeEk]

I said it was a Youtube downloader. I fetch and parse the contents of:

www.youtube.com/get_video_info?video_id=[ID]

Youtube generates a unique key for every request made and the key is only valid for the IP it was generated for.

I suppose I could use fpassthru or readfile to facilitate the download through my server, so my server would basically be a proxy, but I'd like to avoid that.