Verus Hash Solana Implementation

This project implements the VerusHash v2.2 algorithm for use within the Solana blockchain environment. It consists of:

1. verus crate: A Rust crate containing the core VerusHash logic, adapted to be compilable for both native host targets (using optimized intrinsics if available) and the Solana SBF (Solana Bytecode Format) target (using a portable C implementation).
2. program crate: A Solana program (smart contract) written in Rust that exposes an instruction to verify a VerusHash solution on-chain. It uses the verus crate for the hashing logic.
3. client crate: A command-line client application that interacts with the deployed Solana program. It uses the verus crate (native host version) to search for a valid nonce that satisfies a given difficulty target and then submits this solution to the on-chain program for verification.
4. origin-impl directory: Contains the original C/C++ source code from the VerusCoin repository for reference.
5. verus/c directory: Contains the C/C++ source code adapted for the Solana SBF environment (portable, no stdlib dependencies, etc.).

Development & Testing Workflow

The current development cycle involves building the on-chain program, deploying it to a local validator (or testnet/devnet), and then running the client to test the interaction.

Prerequisites:

• Rust toolchain installed (rustup)
• Solana CLI tool suite installed
• A running Solana validator (e.g., solana-test-validator)

Steps:

1. Build the Solana Program: Compile the program crate into the SBF bytecode.

   cargo build-sbf
   # This command compiles the program and places the output (`program.so`) in the `target/deploy/` directory.
   

2. Deploy the Program: Deploy the compiled program to your target Solana cluster (local validator, devnet, etc.). You'll need the program's keypair (e.g., program/target/deploy/program-keypair.json generated by cargo build-sbf if it doesn't exist, or provide your own).

   Example using the default keypair location and deploying to localhost:

   # Make sure your Solana CLI is configured for the target cluster (e.g., localhost)
   # solana config set --url localhost
   
   # Deploy the program
   solana program deploy target/deploy/program.so --program-id program/target/deploy/program-keypair.json

   Note: Replace --program-id with the actual path to your program's keypair file if it differs.

   Take note of the Program ID output by the deploy command. You may need to update PROGRAM_ID constant in client/src/main.rs if it changes or if you are deploying with a specific ID.

3. Build the Client: Navigate to the client directory and build the client application.

   cd client
   cargo build

4. Run the Client: Execute the client application. It will connect to the RPC endpoint specified in client/src/main.rs (defaulting to localhost), search for a valid nonce using the native VerusHash implementation, and then send a transaction to the deployed program to verify the solution on-chain.

   cargo run

   The client will print output indicating whether the nonce search was successful and whether the on-chain verification passed or failed.

This cycle (modify code -> build program -> deploy -> build client -> run client) is repeated as needed during development and testing.