This is a library to assist with implementing custom HTTP Gamestats servers as used by some games formerly hosted by the GameSpy network.
Since my experience with the protocol is limited to Nintendo DS games, there are bound to be some design assumptions I've made along the way which may not always hold. If this library doesn't support a particular game's usage, please send a pull request or open an issue. Please send packet captures with any pull requests or new issues so I can verify your fix.
In general, you'll want to perform URL rewriting in your global.asax handler to forward the game's .asp requests to the .ashx file where you implement your gamestats logic. In the .ashx handler, instead of implementing IHttpHandler, you will inherit from GamestatsBase.GamestatsHandler and add a constructor where you provide the game-specific secret constants. (These constants will be contained within the game binary and helping you find them is outside the scope of this project.)
Please see the included (albeit incomplete) Tetris DS example and the more robust Poké Classic Framework project for examples of this library in use.
This is still a work in progress and I make no promises that there won't be breaking changes in the future.