Bitcoin Node Handshake Project

This project demonstrates a handshake with a Bitcoin node using the Bitcoin P2P protocol. The handshake involves sending a version message and waiting for a verack message from the node.

Getting Started

Prerequisites

• Docker
• Docker Compose
• Go

Setup Bitcoin Node

To run a Bitcoin Core node using Docker, use the provided docker-compose.yml file.

The bitcoin node data will be stored in a directory called bitcoin-data at the root of the project.

Run the following command to start the Bitcoin node:

docker-compose up

Important: Wait for the Bitcoin node to start fully before launching the handshake project.

Running the Project

To build and run the project, use the provided Makefile. The Makefile includes commands for building, running, and testing the project.

• To build the project: make build
• To run the project: make run
• To test the project: make test

Project Overview

This project implements a handshake with a Bitcoin node by following the Bitcoin P2P protocol documentation.

Go Routines

The project uses two main goroutines for handling network communication:

1. Read Goroutine: Continuously reads messages from the Bitcoin node.
2. Send Goroutine: Handles sending messages to the Bitcoin node.

Connection Management

• The connection is closed once the verack message is sent and received.
• If an unknown command is received before verack, the connection will be closed.

Version Checking

The project includes version checking to ensure the received version message is valid. It verifies the magic bytes, command, checksum, and payload length.

Configuration

The configuration is directly put in the Go code, but ideally, it should be in a config.yaml file with more validation. This would make it easier to manage and validate configurations.

References

This project uses the Bitcoin P2P protocol documentation as a reference:

• Bitcoin P2P Protocol Documentation

Example Configuration

Here is an example of the configuration used in the project:

const (
    ProtocolVersion = 70016
    Services        = 1
    UserAgent       = "/Satoshi:0.21.0/"
    StartHeight     = 0
    NodeID          = 12345
    BTCNodeHost     = "127.0.0.1"
    BTCNodePort     = 8333
    Host            = "0.0.0.0"
    Port            = 8333
)

This setup allows the project to connect to a local Bitcoin node running on 127.0.0.1:8333.

Conclusion

This project demonstrates a basic handshake with a Bitcoin node using Go. It includes reading and sending messages using goroutines, managing the connection lifecycle, and validating messages according to the Bitcoin P2P protocol.