The repo contains multiple cryptographic flows, to be executed in web and mobile applications (client side):
- Keypairoom: keyring generation flow
- Coconut: zero knowledge proof, attribute based credential, with user authentication, based on the Coconut paper
- Reflow Multisignature: anonymous homomorphic multisignature flow on BLS12381, solving rogue-attacks issue Reflow paper
Zencode is executed by the Zenroom VM running inside the client as a binary or a WASM assembly packages in NPM.
The language documentation is found on dev.zenroom.org.
The keypairoom directory contains the scripts used to create a keyring.
The coconut directory contains the scripts used to manage the zero knowledge proof flow, client side.
The reflow directory contains the scripts used used to manage the reflow Multisignature flow, client side.
The test directory contains unit tests (single scripts tested in local) and integration tests (shell scripts that call staging instances to test its api).
Below are detailed the crypto exchanges taking place in the repo.
sequenceDiagram
autonumber
participant U as 🤓User
participant C as 📱Client
participant S as Server
S->>S: Configured with secret salt
C->>U: Greets, asks email, name and challenges
U->>C: Answers email, name
C->>+S: Sends name and email to server (ASAP)
S->>S: Verifies email is not a duplicate
S->>S: Compute HMAC of email with secret salt
S->>-C: Sends HMAC (ASAP)
U->>C: User provides answers to challenges
C->>C: Generate SEED with PBKDF of HASH(answers) with HMAC
C->>S: (Optional) Generate KDF dictionary of individual answers
C->>C: Generate public keys from SEED
C->>S: Sends public keys
- 1: Secret salt is generated at server install and saved as an HEX string in its configuration
- 2: Interactive GUI poses all questions in one page: email, name and 5 challenges
- 4: As soon as User answers name and email, reactive page sends them to server (ASAP)
- 7: As soon as Client receives HMAC the Submit button is green
- 8: May happen in parallel while Client and Server are handshaking the HMAC (ASAP)
- 9: May need User confirmation that the answers given to challenges are OK
- 10: Useful to facilitate seed recovery: the server can check validity of single answers
- 12: Start with EDDSA public keys, seed is reused for more key types when needed
Client Zencode
Copyright (c) 2021-2022 Dyne.org foundation, Amsterdam
This program is free software: you can redistribute it and/or modify
it under the terms of the GNU Affero General Public License as
published by the Free Software Foundation, either version 3 of the
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but WITHOUT ANY WARRANTY; without even the implied warranty of
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