61–70 of 101 posts
I see a flaw with that prng scheme. Since AES is reversible, the 128-bit blocks that make up the output cannot repeat. The output is a permutation of distinct 128-bit blocks. Early in the sequence that only matters a tiny bit, but the longer it goes, the more that tells you about possible upcoming values.
https://security.stackexchange.com/questions/27776/block-cha...
I'd be curious if people on HN would want a zero knowledge survey and voting system inside Keybase, and if so, what would it look like? The background: we talk about it sometimes as a solution to a real problem: in certain teams and workplaces, people can be afraid to give honest feedback (who dares to submit an "anonymous" survey to HR?), but Keybase may be in a unique position to let people in a group give written…
I'd be curious if people on HN would want a zero knowledge survey and voting system inside Keybase, and if so, what would it look like? The background: we talk about it sometimes as a solution to a real problem: in certain teams and workplaces, people can be afraid to give honest feedback (who dares to submit an "anonymous" survey to HR?), but Keybase may be in a unique position to let people in a group give written…
There's a slight variation on this that I had pondered for designing a distributed election algorithm. I'm sure the idea is not novel, but it would be nice to know what work has been done on it. The goal is to fairly select some candidate from a set of candidates. Each candidate `Ci` generates a UUID `Ui`. The hash of their UUID `hash(Ui)` is published by each candidate. Once all hashes have been collected, each cand…
Earlier quoted context omitted.
This is generally referred to as a RANDAO in cryptoeconomics. The problem is that a candidate can decide not to reveal their preimage `Ui` and affect the outcome of the RANDAO in that way. https://github.com/randao/randao
Interesting! Thanks for the reference. I'm not sure how not revealing the pre-image would allow them to affect the result with any degree of predictability - it is equivalent to them selecting a different uuid, is it not? I'll try to read up and see if I can answer that question.
I'd be curious if people on HN would want a zero knowledge survey and voting system inside Keybase, and if so, what would it look like? The background: we talk about it sometimes as a solution to a real problem: in certain teams and workplaces, people can be afraid to give honest feedback (who dares to submit an "anonymous" survey to HR?), but Keybase may be in a unique position to let people in a group give written…
OT: One of the things I find interesting is that "zero knowledge" has become a buzzword. On the one hand it is frustrating, because when cryptographers say "zero knowledge" we mean something very specific and rigorously defined (a survey protocol cannot be zero knowledge because the results of a survey do reveal something about the respondents' inputs). On the other hand, the fact that non-experts are comfortable wit…
Earlier quoted context omitted.
Interesting! Thanks for the reference. I'm not sure how not revealing the pre-image would allow them to affect the result with any degree of predictability - it is equivalent to them selecting a different uuid, is it not? I'll try to read up and see if I can answer that question.
Say that all the other participants have revealed their pre-images, and you're the last one left you reveal your pre-image. Before you reveal it, you realize you alone have all the pre-images and can calculate the result. You calculate it, and realize you don't like the result. You could then decide to throw away your pre-image to force a new roll. If necessary, claim your computer crashed, your connection dropped, e…
Is this a problem with commitment schemes? I want a heads to come up. I add a couple of hacked members to the group, so there are 3 honest members, and lets say 3 coordinated dishonest members. Everyone shares their commitment hash, and the dishonest members share their actual commitments amongst themselves. Once everyone has the commitment hashes, the 3 honest members broadcast their commitment. The three dishonest…
2. All members submit a hashed value of that random value (the commitment).
3. All commitments are distributed to all members. At this point, no more commitments may be submitted.
4. All members reveal their random values to each other and validate each value against its hash.
5. All values are then used to deterministically calculate the coin flip.
A dishonest member will not receive any values used in the coin flip calculation before step 4. If a member decides to change their random value, the hashed value / commitment will be invalid.
@malgorithms, what are the colored bars from each participant? Is it a colored representation of the hashes?
Yes! Each horizontal row in the rectangles represents a participating device. The purple/blue rectangle that comes in first represents all the bytes of the commitments coming in. Since we constrain the size of the rectangle it makes (IMO) a cool visual effect as the rows squeeze to accommodate more data. Each little square inside it represents a byte, so we map bytes (0..255) to colors ranging from a blue to a purple…
This may not be the intended use of your application, but I organize a local bdsm group (if unfamiliar, do not Google this at work), and we appreciate the security offered very much. We can even think of a few "fun" uses of this new feature.
Speaking of NSFW stuff in Keybase… Since the end of January 2019 I’ve started to notice more and more profiles with suggestive pictures of underage humans and anime characters. I almost never log into my Keybase account, but frequently check my profile to see “friend” recommendations, then I log in and follow people who I think are interesting, mostly tech influencers. But since January-February I randomly get recomm…
What I don't get is the whole "Consider following" thing. But then, I don't use Keybase as social media, per se.
About the suspected pedophile network, you'd think that they'd be more discreet.