ZK HACK III - Puzzle 2 Recap

Transcript

foreign I want to say welcome to everyone who's arriving this is ZK hack3 and here we are in the session number five so as as you may know this is like a multi-week event we do two workshops a week over the span of almost a month and we are actually at the halfway mark today uh just over the halfway mark so yeah we have this amazing session for you today we're going to be doing just to kick off oh actually I have the agenda so I'll just I'll continue on um maybe to start I'll tell you a little bit about like what ZK hack is all about

or what you can do uh if you're here you're going to be joining a workshop but I don't know if you're familiar with our puzzle hacking competitions but you can also hack a puzzle you can win a prize so what these are like broken ZK protocols and the goal is to exploit the vulnerability and solve it as quickly as you can and then you know submit it for a prize uh here we are so this is the agenda for the day we're going to start the day with this sort of intro session and we're actually going to be announcing the winners of puzzle two T2 uh I know there was a few people who submitted kind of after the deadline this time around but we will also be around this time like over the next hour so publishing the solutions page so you can

see actually how to have solved uh puzzle T2 after this we're going to be hearing from risk zero they're going to be sharing their workshop building on-chain apps off chain using risk zero and then at the end of the session so in two hours from now we're going to be announcing the start of puzzle T3 and then there'll be a week to solve that I do want to highlight next like the the coming sessions as well uh if you're not signed up yet next or actually in two days on Thursday we have o of one Labs presenting Mina ZK apps and we also have the privacy and scaling Explorations group from the ethereum foundation who will be doing a workshop on building a ZK dial with uni rep protocol so if you

haven't yet sign up for those uh it's basically the same it's DK hack iii-6 oh you can already almost guess what the URL will be oh there it is and we've also added it in the chat and then on next week our finale is a workshop with Elio who will be presenting Leo language and Elio and we'll be doing sort of a final you know wrap up and winner ceremony awarding prizes to everyone who participated in the puzzles cool so if you're not familiar with our kind of website or where everything is this is the website check it out there you can find a schedule you can find

previous videos of you can find videos of previous workshops you can find the current puzzles you can find the previous puzzle solutions as well as the leaderboard so that's you're going to see kind of later today we're going to be updating the leaderboard with the new winners all right um so there's also this great Hub if you like want to see more if you want to learn more just generally about like the ZK hack project ZK Tech generally there's a ZK mesh newsletter you can sign up for off of the ZK hack this is just zekehack.dev you can also sign up for the wipe or you can watch a lot of the Whiteboard sessions these are like really good educational content in the field of ZK so if you're more beginner

that would be a really good thing to check out I hope you're already on the Discord that's where we live when we're not here on hoppin and you can also follow us on Twitter and just a note people always ask is this recorded yes it is recorded it will be on the on the YouTube channel of the zero knowledge podcast so if you want to find if you want to get that video quickly then be sure to subscribe to that uh channel uh otherwise we are sharing it in Discord and you'll also find it on our website after it airs we usually try to get the videos up as quickly as we can we try for the next day sometime for a little bit later but we're pretty quick all right so now I'd like to invite Kobe

and oh actually I'll first invite Kobe to the stage and then uh we can invite some other folks to the stage as well hello hi hi hi Kofi so for anyone who's not familiar Kobe always shows up to the zika hack videos as something the theme for this entire zika hack 3 seems to be planets what planet are you today do you know your Jupiter very nice I aggressively chose a guest giant yeah very nice cool cool okay do you want to share a little bit about the puzzle yes definitely so the puzzle this time was

designed and created by um then bonet's group in Stanford and it was around the qian attack so we can describe it more in detail soon but uh the context is that it's a kind of attack that's very relevant in the world of snarks because the kind of structure that you have when you do a trusted setup Blends it very it fits very well and the the structure that the qian attack targets and it allows you to basically gain knowledge about the secret tile that nobody should know because if they

know it they can create fake proofs so it was a pretty challenging puzzle we got 18 submissions in time and a few more not in time um but we did see that people it was a bit harder it was challenging even the fasted solvers took some time and we got Solutions trickling in and we got really really good write-ups we had to choose one that's really a few good ones should I Kobe should I should I invite a few of the other guests to the stage that would be amazing so I'm going to invite Aditi and Dan to

the stage hey everyone hi hey we'll just wait for IDT to also get up uh yeah Kobe do you wanna I mean maybe just continue on what you were saying I know I just interrupted you a little bit there ah no not at all so just saying that we got really good write-ups and um yeah it seems that people have figured out all the possible ways to solve it and the the various tricks that are needed to make this efficient and solve it in 20 minutes instead of a few days which was uh really impressive to see and uh yeah I

think then an adity could tell a bit more about the context of or the puzzle yeah maybe I can go first and then you can can add so uh congratulations everyone who solved it amazing to see all the solutions I really enjoyed look we both we actually really enjoyed looking over your write-ups so that was that was fantastic um maybe the the thing to say here is uh what this what this puzzle shows is when you set up this powers of Tau that are needed for snarks and other applications it's actually important to be careful how you choose your curve if it so happens that your group has a moderate size Factor you know the size of the group minus one or the size of the group plus one has a moderate size Factor then you can speed up the computation of this

grid log just like you saw in this puzzle so I guess people who did the puzzle learned a little bit about discrete log algorithms learned how to use the pairing and yeah I was really excited to see that so many of you solved it so yeah congratulations everyone one thing we did learn about this particular puzzle this one took like there was you actually had to run some sort of computation right this was unique we hadn't done that before had we Kobe no we this was the first time it's kind of a rate limiting on how many attempts you can do right totally I'm curious like yeah what was the how was the decision made on on how to like

do that you know was there like I think I think we had a bit of back and forth wasn't like one of the original builds like two hours long to run or something like that we had to like lower it yeah DT can talk about that uh yeah so basically on the tags which is like the discrete log even though it's pretty fast uh like just because the group was decently big it would like take actually not not to us like more than a few days so like we uh leave it like we did a few things to improve that the first was like improve the exponent function like we made a more efficient one and the other thing we did which was like Dan's idea was like we actually revealed a few more bits uh related to the answer so that was eventually what helped us like

you know really bring down the the runtime of the puzzle yeah very cool well thank you yeah one other cool thing that uh yeah just and just one thing that I remembered actually when they when they worked on it Tricia and Aditi they actually found a bug in artworks uh which was really interesting so it was fixed a few days after the puzzle started but they had to implement a bunch of stuff from artworks and have people use that so that was a nice contribution to the open source community so that's really cool yeah so it's always great when a puzzle

leads to uh unusual applications so that we can expose bugs in code and yeah it's great that uh there are developers by the way reacted really well and fixed the problem right away very cool all right so I think we are now at the point where we're going to be giving out the prizes to the winners so why don't we do that so the way this works is we have different tiers of prizes the first we'll be getting 2 000 usdc second place will get a thousand usdc the third will get 500 and we also have a special price for the best write-up all of these prizes will be uh distributed on the finale this is different from previous editions but uh you'll be getting it next week

um yeah so I think we can start the drum roll I think Kobe do you want to read out the winners as they come yeah that's it okay so in third place we have a new entry yeah so um yeah I'm not sure how to read the name but uh thank you that was really interesting and uh you made some good comments and as to how we we could communicate things uh more clearly and but congrats like you you solved it really fast and uh and yeah good going cool all right in second place we have

yeah so we we know you we we already saw you in the first puzzle and in previous puzzles uh congrats congrats and in first place this time around we have yeah and yes again a returning winner um so it's uh Nicholas from Ledger and um yeah we will also say that the he was pretty good in another manner yeah so we always give out a write-up we usually it's kind of rare that it's actually going to someone in the top three but I think a DTU we after looking through them this was the one that was uh really highlighted so the winner for the solution write-up

is also uh how do you say it's Nico no I believe it's Nicholas Nicholas okay I'd love to see I mean some of these handles are so awesome I wonder how people pronounce them in their head for me it's been like Neos NEOS Ledger anyway yeah so I think that straight up was super interesting it was very extensive it described all the details and it even described the bug in the artworks which was really fun to see so I went to anyone that wants to understand how that Tech needs to be performed from zero to n this write-up is extremely educational so I recommend everyone to read it when we once we put it on the side

very cool Kobe when can we expect to see that so when we launch puzzle 3 at the end of the workshop today okay then we will also see the leaderboard the solutions and um the write-up yeah Perfect all right thanks everybody and yeah thanks congratulations so much everyone [Music]