Re:Timelock Encryption made possible and easy to use
by heinrich5991 on Tuesday August 16, 2022 @12:38AM
(#32479251)
> To me the beautiful thing about trying to get randomness is that as long as you have one random source then you have randomness. I.e. non-random XOR random => random.
Only if the sources choose their numbers independently of each other. If the non-random is a function of the random source (e.g. the identity), then the result isn't random, it's a constant 0.
Re:Timelock Encryption made possible and easy to use
by anomalroil on Tuesday August 16, 2022 @02:45AM
(#32479877)
Also, be careful of a "last player attack" when XORing randomness: if your last source could spy on the state of your buffer, or on all other randomness sources, it can trivially craft a string that would XOR to a specific value once XORed with the other sources.
To me the beautiful thing about trying to get randomness is that as long as you have one random source then you have randomness. I.e. non-random XOR random => random.
So, you use X sources, as long as one of them is truly random then you are golden. Even if most are compromised it shouldn’t matter. Use on device security chip randomness, use user input, use external party providers etc. it all helps! (But be careful to errors when implementing, that’s hard to do!)