I am currently making a game with randomly made levels, but I have an interest in making everyone play the same level in a daily challenge section, like Spelunky.
At first I thought about letting the clients decide the seed based on their date, but dates can be locally spoofed.
I have access to a parse.com free account, so I can execute code in the cloud and expect results back. So then I considered asking cloud code for a hash based on the current date, but this could be spoofed to play a different level while sending the server the score for THAT level instead of the daily one.
Then I thought of encrypting the date in the server and decrypting it on the client, but then this might be problematic if I used symmetrical encryption. So... maybe use assymetrical encryption?
Am I missing a simpler solution here? This feels like I'm overcomplicating myself, but I'm not sure. Is there a generally accepted solution for this kind of problem? I haven't found anything after googling for a good while.