Encrypt that Save file

I am working on the Xbox save file tonight. It is one of the last major (?? maybe) items that are lying on my list awaiting time to be done. Tonight is the night. I have been feeling quite unwell today, but tonight i am on a nice eve keeled coding spat.

So i am working on something that actualy works already, the save game. Only i want to offer prizes out for top scores etc once the game goes live. Not that i will be able to advertsie that in game :(  But that is anotehr story and complaint. Onto the happier thoughts.

To see scores of course i want them to be shared and have spent a large amount of time getting that working seemlessly. I am happy with that, but i already knew from another Dev that people were hacking the save game files. They are in fact relatively easy to hack being Xml format. So i have decided i want to encrypt my save files so that it will at least stop the occasional hacker. I also have a verification system in place to hopefully stop the next level of hacker up. Time wioll tell if all this actually works well enough to stop people hacking top scores into the save file. I sure hope it delays them more than a month, till i give out the T-Shirt and Hat prizes etc.

Still it is a lot of work to stop these unplayed for scores. Wish me luck that i make it hard enough to at least put them off for a while. I mean, is a T-Shirt worth hacking the scores for? Obviously i don't know. It is after all only a small group of people that even sees them, never mind plays them.

Laters.

Encryption For Competition

Tonight i started on encrypting my save game data. The reason i need to encrypt it is so i can  run a competition or two when my new game A Shooter comes out. I want to run a  few competitions based on the score that people can achieve. so rewarding the best players (or most dedicated). However i know people will cheat when there is a prize on the line.

So i worked out what algorythm i will use to encrypt the data, but i am a little disconcerted at this point. Ya see, it doesn't matter how much time i put into encrypting the data, it will always be crackable. There are several well known and documented ways to do this and all of them will work given enough time and dedication. So the question is, just how robust will it be? I know that it is only going to be an Xblig game, so will probably be overlooked by many people. Though i know some people will regard it as more of a challenge than actualy playing my game. Once cracked of course the unscrupulous hacker can insert any score he feels like.

So what do i do? How long do i spend on this, how many layers of self and extra checking should i put into it? I certainly don't have the answer at the moment. Needless to say, if i get to run a top score competition, then i will need to feel it has some level of validity.

G'night