Programmable HSMs, with verifiable software (e.g. via a key ceremony), removes the need to trust a shard holder to do counting correctly. You know what software they're running, so you can verify it works as designed.
Making encryption more convenient for everyone is definitely a good thing. Some people will always have that paranoia around letting keys out of their hand, but for the rest of us this protocol aims to reduce the need to trust any one service with your key material by distributing it across independent distrusting services.
TL;DR we're sharing an open-source encryption key recovery protocol that provides high security coupled with a user-friendly design, to make encryption further accessible to larger numbers of people. What we've built leverages programmable HSMs, distributed cryptography, and a user-friendly PIN-based recovery process to simplify key recovery without compromising security.
I'm not a cryptographer- what's the attack/failure mode of "standard HSM key recovery, but the 'PIN' sent to each realm is actually HMAC(some_identifier_for_each_realm, PIN), and each realm stores just one share of the secret"- i.e. what motivates the use of OPRF here instead of just HMAC to prevent a realm from basically pass-the-hash-ing the user's PIN to get shares from other realms?
The issue if realms stored HMAC(realm_id + PIN), where PINs are presumed to be low-entropy, then an individual realm could brute-force the PIN. Specifically, an adversary with access to a single realm's database could enumerate PINs, run them through the HMAC along with the realm ID, and test locally whether that's the correct PIN. That would already be bad because users might reuse PINs across services. Then, if the adversary had valid auth tokens for other realms, they would be able to use that PIN to recover the secret shares from other realms and reconstruct the secret.
The Juicebox protocol is designed to prevent this. A realm can't individually test whether or not a PIN is correct.
Note: I'm a former employee of/contributor to Juicebox.
What work does "individually" do in this last sentence? Can 2 evil services collaborate (or more realistically 2 non-evil services get breached) to extract part of the secret? What is the mechanism keeping me from setting up n realms and extracting secrets from their shared info?
Yes, that is the work "individually" is doing here – multiple realms (services) could collude to combine shards and attempt to extract secrets.
However, programmable HSMs, with verifiable software (e.g. via a key ceremony), minimize this form of collusion. The shards they hold can't be extracted by a malicious operator, at least without substantial effort (requiring HSM hardware vulnerabilities).
Besides "how do we use this" any word on the authors of this project? I did a very cursory search of the two contributors and there was very little I could find that would reassure me in using such a sensitive tool. Could well be my heightened paranoia after recent events.
Juicebox's design of distributing secrets to n independent services sounds similar to Lit Protocol's threshold signature schemes. Is this in the same problem space or no?
It’s a different problem space. Lit seems very focused on the MPC use case. They are using some similar, albeit less strong cryptographic techniques, but at their core (based on https://developer.litprotocol.com/v3/resources/how-it-works) they seem focused on MPC, blockchain applications, and more social key distribution.
Juicebox is very focused on how does an individual user manage their private key for one service, in a simple and user-friendly way, without any compromise in security. Think like your keys for Signal, WhatsApp, or any other E2EE service. It could also be used to manage a wallet private key for a noncustodial wallet.
As far as I can tell, Lit also manages all the nodes available to you (even if they don’t personally run them). There’s not a freedom for you to run your own nodes. This is the most important thing for this kind of distributed cryptography to be used securely, and something Juicebox supports by default – all our server code is available on GitHub and we encourage people to host their own realms to build networks with appropriate trust characteristics.
It's the same space but most "solutions" in the space (like Lit Protocol) are actually custodial solutions parading as non-custodial. If you look closer at Lit Protocol, you will see that their nodes are unknown and unamed providers. Reading between the lines, it's just Lit hosting everything.
I actually just has a call with David from Lit Protocol. He patiently explained some of the nuanced pieces of Lit Protocol. A lot of this information is out there but they are moving so fast that it's hard to find. They are going to update their docs to make it more apparent but they have named their providers and appear to have a robust distributed network for key storage. Sorry for the hasty comment! It looks like Lit Protocol is one of the few non-custodial and resilient systems out there.
Savant is a home automation company, based heavily on the Apple platform. A Mac Mini or Linux host is used as the server to control your home, in tandem with our custom AV switches, lighting systems, and HVAC systems. Once setup, your home can be controlled from our iOS apps, our traditional remotes, or our new Android based universal remote.
I'm a Software Engineer at Savant, and working there is definitely a great experience. You may fill one of these roles below, but you'll get to work on a wide variety of projects, regardless your role. To give you a brief picture, day-to-day, I will work on firmware, Mac apps, iOS apps, Node.js web apps, and daemon processes that run on Mac and Linux.
We're looking to fill the following roles ASAP:
- Senior iOS Developer
- Junior iOS Developer
- Android Developer
- Android Platform Software Engineer
- Firmware Engineer
- Linux Software Engineer
- Media Software Engineer
- Web UI Developer
- Junior/Mid-Level Web Developer
Support the older rev for a while (with multiple devices, not upgrading, blobs). When apple stops supporting an older device, next major release shifts the target to whatever the minimum iOS was on the next newest device when it shipped (usually just a few revs higher). This way, we support whatever hardware apple supports on every possible iOS. iOS 5 will make this trickier.
Also, if there are significant bugs on apples part in a particular iOS that hamper our app, we'll drop it early.
