OAuth Callback "Service"?

Question

Is there any service available that would allow someone to set up an OAuth callback service?

Example... I direct a user to Google to authenticate for Google Drive. This doesn't always originate from my website.. it could be from another application on a terminal, a user built website that's using my application, etc. The callback is www.callbackservice.com/callback/oauth (instead of something like www.mycompany.com/callback/oauth).

callbackservice.com now stores the OAuth 2.0 code for me to retrieve via cURL, etc..

Most of these services (at least google and ms) allow you to provide a session key (state) and credentials that could be used to retrieve the code. Then I just do another cURL to exchange for a token.

The purpose of this would be so that if for any reason my web server was down there would still be a service out there to keep things going. Or if my company was bought out they wouldn't need to rely on my web server to keep customers happy. They simply use their own systems.

Thanks for entertaining this.. I couldn't find anything about this online, which probably means that it isn't available for security reasons.