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A trapdoor back door would require knowing some secret value. It is very much possible that this secret value could remain secret by not being written down in a
by garmaine 7y ago
A trapdoor back door would require knowing some secret value. It is very much possible that this secret value could remain secret by not being written down in any electronic document. It would exist on some code breaking hardware, but like the cocoa cola recipe it could be known by only a few people in the world and still be useful.
- ev0lv 7y agoSomewhere exists a hardware key that breaks the blockchain encryption. This is a sweet movie idea.
- bonestamp2 7y agoSeems like the typical heist movie at first, but the main action arc is just to steal the hardware key. Steeling the actual (digital) coins is then the most boring part of the film.
- whoopdedo 7y agoThat's why you make the thieves be white-hats hired by the government to steal the key. Then it becomes a cloak-and-dagger affair where you have to unravel who's working for who and which side is really the bad guy. And decrypting cryptocoins is too obscure. For maximum effect, make the key able to break all encryption.
- chowells 7y agoSomeone already made Sneakers.
- 0xcde4c3db 7y agoI think that's the joke.
- chowells 7y agoYes? When someone puts some effort into making an indirect reference like that, they appreciate their work having been noticed. That's the role my comment was performing.
- garmaine 7y agoWe know this not to be true. The origins of the secp256k1 curve used to be nothing up my sleeve numbers for the parameters which matter.
- nullc 7y agoThe construction of the NIST curves essentially preludes trapdoors. It doesn't completely preclude having a purposefully weak curve based on some publicly unknown weakness. ... but at the same time it also doesn't preclude the the curves having been selected to be stronger against some publicly unknown weakness (as was done with DES). [Not that I'd recommend them.]
- deleted 7y ago[deleted]
- garmaine 7y agoGreg, do we know that to be true of all use cases though?
- nullc 7y agoWould you clarifying your question a bit? My comment was pointing out that those NIST curves like P-256 and P-224 can't have a trapdoor-- meaning a hidden secret key that allows the NSA and only the NSA to compromise the use-- in the curve themselves. Some application of the curve could have its own trapdoor, as dualECdrbg did.
- garmaine 7y agoWell the NIST curves use random primes, and they're not the obvious, largest possible primes that meet the necessary security requirements. So maybe they were chosen according to their susceptibility to some unknown attack (or, charitably, their non-susceptibility). I think we agree up to this point. But when the space of potential attacks is an unknown-unknown, can we really constrain with confidence what attacks might exist? Maybe the prime group was chosen to have some relationship to a composite group for which the NSA knows the prime factors? I know this doesn't jive with our current understanding of number theory, but the point is it is hard to speculate about unknown-unknowns. Can we be certain that every crazy thing we think of is ruled out by our proven, not conjectured understanding of number theory?