basic readme

README.md

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+# Fair and temper-proof random-number-generation in a distributed environment
+
+As long as you can contribute an unpredictable (random) number of your choosing, the algorithm will make sure the outcome is unpredictable.
+
+
+First a public "vote" is held, where everyone secretly generates an unpredictable number and shares a digest to later verify it (HMAC in this proposal).
+After receiving all HMACS, one sends out the number and starts receiving all the others and verifies them.
+Now we have random numbers that need to be combined in a predetermined way that mangles them seemingly randomly and temper proof (very expensive).
+For this a hashing chain is chosen.
+
+# Algo
+
+## init
+InitialState (IS) contains a unique(-ish) id, to uniquly identify this random number
++ any extra data thats usecase dependent. (like the set of cards we are choosing from)
+
+-> hashed to get a fixed sized SI
+SI = H(id + user data)
+
+## rng?
+use an unpredictable rng. Simple prng dont cut it, since their state can be reconstructed form very few numbers.
+(use system crng or seed own chacha crng with system crng ...)
+
+## hmac
+message is the rng (while possibly variable in size, should be same as output of H() )
+key is random
+
+send HMAC to everyone
+
+## collection
+wait for everyone elses HMAC
+send out secret message (rng) and key
+verify everyone elses message
+
+
+do not proceed until everything is verified.
+either hardblock if someone is not responding (to prevent a retry-attack) or exclude unresponsive/lying peer in next (retry) generation.
+
+## post processing
+
+combine IS with all the numbers
+
+for each M do
+  H(M + prevH)
+result = H(IS + prevH)
+