solana-examples

Solana Zero-Knowledge Proof Example Project

This project demonstrates how to use the RISC Zero zero-knowledge prover with Solana. It provides an example Solana program that implements a simple nonce increment system where users must provide valid ZK proofs to increment a nonce value on-chain.

Project Structure

The project consists of several key components:

• Solana Programs: Smart contracts that handle on-chain verification and state management

  • verifier_router: Routes proof verification requests to appropriate verifiers
  • groth16_verifier: The RISC Zero Groth16 verifier that performs the proof verification
  • solana-examples: Example program that uses the data from a RISC Zero Proof

• RISC Zero Guest Program: Off-chain program that generates proofs

  • Located in hello-world/methods/guest
  • Implements nonce increment logic that will be proven

• Host Program: Rust program that acts as the Solana client and submits data for proving

  • Located in hello-world/host
  • Initializes the Solana example program account on first run
  • Handles proof generation and submission to Solana

Prerequisites

• Rust and Cargo
• Solana Tools
• Anchor Framework
• Node.js and Yarn

Setup and Installation

1. Configure Local Environment:

# Configure Solana for localhost
solana config set --url localhost

# Generate a new keypair if needed
solana-keygen new

2. Start Local Validator:

# Run this in a separate terminal
solana-test-validator -r

3. Build and Deploy the Verifier Router System:

# Go to the Solana Verifier programs to deploy them locally
cd solana-verifier

# Install the dependencies for the scripts
yarn install

# Sync keys for local deploy
anchor keys sync

# Build the programs so that IDLs are generated
anchor build

# Generate client code for scripts before first run
yarn run client

# Deploy the programs locally
yarn run deploy

4. Build and Deploy the Example Project:

# Go to the Solana Examples directory for everything else
cd solana-examples

# Sync keys for local deploy
anchor keys sync

# Build the program
anchor build

# Deploy the program locally
anchor deploy

Running the Example

# Go to the Client program directory
cd hello-world

# Run the example program
RUST_LOG=info cargo run

This will:

• Generate a fresh keypair and request an airdrop (to demonstrate anyone can submit proofs)
• Initialize the Solana example program on the first run
• Generate a ZK proof for incrementing the nonce
• Submit the proof to the Solana program
• Verify the proof on-chain
• Update the nonce if verification succeeds

Understanding the Flow

1. Initialization

   • The Solana program initializes with a starting nonce of 0
   • It stores the RISC Zero image ID to ensure proofs come from an unmodified program

2. Proof Generation

   • User requests to increment nonce
   • Host program loads current nonce from Solana
   • Generates proof using RISC Zero guest program
   • Proof demonstrates user of the signing account has run the guest program

3. On-chain Verification

   • Host submits proof to Solana program
   • Program validates:
     • Proof is for correct image ID
     • Nonce value is incremented correctly
     • Sender's public key matches proof
   • If valid, nonce is incremented

Key Components

Solana Program (programs/solana-examples/src/lib.rs)

Handles on-chain state and verification logic:

• Stores current nonce and program image ID
• Verifies proofs through Verifier Router
• Updates state when proofs are valid

Guest Program (hello-world/methods/guest/src/main.rs)

Simple program that:

• Takes current nonce as input
• Increments nonce value
• Outputs incremented value and public key into the proofs journal

Host Program (hello-world/host/src/main.rs)

Orchestrates the proof system:

• Initializes the Solana example program if not currently initialized
• Reads current state from Solana
• Generates proofs using guest program
• Submits proofs to Solana program

Development Notes

• The Verifier Router system must be deployed before the example project
• Use solana logs to monitor program output during testing
• Program IDs are deterministic based on Anchor.toml configuration

Troubleshooting

If you encounter issues:

1. Verify local validator is running:

solana cluster-version

2. Check account balance:

solana balance

3. Reset local validator if needed:

solana-test-validator -r

4. Verify program deployment:

solana program show --programs --all