Hyli-noir

A TypeScript/JavaScript library providing Noir-based zero-knowledge proof functionality for the Hyli ecosystem. This library enables secure secret verification through cryptographic proofs without revealing sensitive information.

Features

• 🔐 Zero-Knowledge Secret Verification: Generate proofs that demonstrate knowledge of a password without revealing it
• 🛡️ Identity-Based Authentication: Combine user identity with password hashing for secure authentication
• 📦 Blob Transaction Support: Create and manage blob transactions containing encrypted secrets
• ⚡ Noir Circuit Integration: Built on Noir's zero-knowledge proof system with UltraHonk backend
• 🔧 TypeScript Support: Full TypeScript definitions and type safety

Installation

npm install hyli-noir

Peer Dependencies

This library requires the following peer dependencies:

npm install @aztec/[email protected] @noir-lang/[email protected] @noir-lang/[email protected]

Quick Start

import { check_secret } from 'hyli-noir';

// Hash a password
const hashedPassword = await check_secret.hash_password('my-secret-password');

// Generate identity hash
const identityHash = await check_secret.identity_hash('[email protected]', 'my-secret-password');

// Build a blob transaction
const blob = await check_secret.build_blob('[email protected]', 'my-secret-password');

// Generate a proof transaction
const proofTx = await check_secret.build_proof_transaction(
  '[email protected]',
  'my-secret-password',
  '0x1234567890abcdef...', // transaction hash
  0, // blob index
  1  // total blob count
);

API Reference

Core Functions

hash_password(password: string): Promise<Uint8Array>

Hashes a password using SHA-256.

Parameters:

• password - The password string to hash

Returns: Promise resolving to a 32-byte Uint8Array containing the SHA-256 hash

identity_hash(identity: string, password: string): Promise<string>

Creates a combined hash of identity and password for authentication.

Parameters:

• identity - The user's identity string
• password - The user's password string

Returns: Promise resolving to a hex-encoded string of the combined hash

build_blob(identity: string, password: string): Promise<Blob>

Creates a blob transaction containing a secret derived from identity and password.

Parameters:

• identity - The user's identity string
• password - The user's password string

Returns: Promise resolving to a Blob object containing the encrypted secret

build_proof_transaction(identity, password, tx_hash, blob_index, tx_blob_count, circuit?): Promise<ProofTransaction>

Generates a zero-knowledge proof transaction demonstrating knowledge of the password.

Parameters:

• identity - The user's identity string
• password - The user's password string
• tx_hash - The blob transaction hash string
• blob_index - The index of the blob in the transaction
• tx_blob_count - Total number of blobs in the transaction
• circuit - Optional compiled Noir circuit (defaults to check_secret circuit)

Returns: Promise resolving to a ProofTransaction containing the generated proof

register_contract(node, circuit?): Promise<void>

Registers the Noir contract with the node if not already registered.

Parameters:

• node - The NodeApiHttpClient instance
• circuit - Optional compiled Noir circuit (defaults to check_secret circuit)

Utility Functions

assert(condition: boolean, message: string): void

Throws an error if the condition is false.

sha256(data: Uint8Array): Promise<Uint8Array>

Computes SHA-256 hash of the input data.

stringToBytes(input: string): Uint8Array

Converts a string to Uint8Array using UTF-8 encoding.

encodeToHex(data: Uint8Array): string

Converts Uint8Array to hex string representation.

How It Works

The library implements a zero-knowledge proof system for secret verification:

1. Password Hashing: The user's password is hashed using SHA-256 to create a fixed-size secret
2. Identity Combination: The identity is concatenated with the hashed password using a colon separator
3. Final Hash: The combined value is hashed again to create the stored secret
4. Proof Generation: A zero-knowledge proof is generated that demonstrates knowledge of the password without revealing it
5. Verification: The proof can be verified against the stored hash without exposing the original password

Security Considerations

• Passwords are never stored in plain text
• The zero-knowledge proof system ensures password privacy
• All cryptographic operations use industry-standard algorithms (SHA-256)
• The system is designed to prevent replay attacks and unauthorized access

Development

Building Noir contract

In ./check-jwt/ folder if ./Prover.toml is present and well constructed

nargo execute

It builds and executes the circuit.

In ./check-secret/, to build without executing do

nargo build

Building library

bun run build

Publishing

bun run pub

License

MIT

Contributing

Contributions are welcome! Please feel free to submit a Pull Request.

Support

For issues and questions:

• GitHub Issues: https://github.com/hyli-org/hyli-noir/issues
• Repository: https://github.com/hyli-org/hyli-noir

Related Projects

• Hyli - The main Hyli ecosystem
• Noir - Zero-knowledge proof language