Eth-Chall-Env

A simplified version of paradigm-ctf-infrastructure for easier deployment of Ethereum CTF challenges.

Overview

This project provides a streamlined environment for deploying Ethereum CTF challenges. Compared to the original paradigm-ctf-infrastructure project, it removes complex features like databases and container distribution systems, retaining only the core blockchain environment and challenge deployment functionality. All components are consolidated into a single Docker container.

Key Features

• Private Blockchain Environment

  • Anvil as local Ethereum node
  • Configurable chain ID and account numbers
  • Support for blockchain forking and state management

• Challenge Deployment

  • Automated contract deployment process

• Account Management

  • Automatic player account and private key generation
  • Preset account balances
  • Secure key management

• Network Services

  • Exposed RPC endpoint (default port: 28545)
  • WebSocket connection support
  • Built-in RPC request filtering and security checks

Quick Start

Prerequisites

• Docker
• Python 3.11+
• Foundry toolchain

Installation

1. Clone the repository:

git clone https://github.com/your-username/eth-chall-env.git
cd eth-chall-env

2. Build Docker image:

docker compose build

3. Start services:

docker compose up

Usage Guide

1. After services start, access through:

   • Challenge interface: localhost:1337
   • RPC endpoint: localhost:28545

2. Deploy new challenge instance:

   • Connect to challenge interface
   • Select "launch new instance" option
   • Wait for deployment and get instance info

3. Interact with challenge:

   • Connect to private blockchain using provided RPC endpoint
   • Sign transactions with provided private key
   • Interact with deployed contracts

Project Structure

eth-chall-env/
├── ctf_launchers/     # Core launcher code
├── ctf_server/        # RPC proxy server
├── challenge/         # Challenge contracts
│   └── project/      # Foundry project
├── docker-compose.yml # Docker compose config
└── Dockerfile        # Docker build file

Configuration

The following parameters can be configured through environment variables:

• PUBLIC_HOST: RPC service public address (default: http://127.0.0.1)
• PROXY_PORT: RPC proxy port (default: 28545)
• ANVIL_PORT: Anvil node port (default: 18545)
• TIMEOUT: Instance timeout (default: 111440)
• FLAG: CTF flag value

Development Guide

1. Adding New Challenges:

   • Create new contracts under challenge/project/
   • Implement isSolved() interface
   • Write deployment scripts

2. Customizing Launcher:

   • Inherit from PwnChallengeLauncher class
   • Override get_anvil_instance() method for environment configuration
   • Customize deployment logic as needed

Security Considerations

• RPC endpoint is filtered to prevent unauthorized methods
• Private keys are securely generated and managed
• Instance isolation through Docker containerization
• Timeout mechanism to prevent resource exhaustion

Troubleshooting

Common issues and solutions:

1. Port conflicts:
   • Check if ports 1337 or 28545 are already in use
   • Modify port mappings in docker-compose.yml

Acknowledgements

This project is based on the excellent work done by the Paradigm team in their paradigm-ctf-infrastructure. We are grateful for their contributions to the Ethereum security community and for open-sourcing their CTF infrastructure.

License

This project is licensed under the MIT License.