Programming Bitcoin in Rust

This repository contains a Rust implementation of the exercises and concepts from the book "Programming Bitcoin" by Jimmy Song. As a Rust developer, I am using the book to learn Bitcoin, but doing the same exercises in Rust, not by copying the python code, but understanding the logic and rebuilding.

Overview

"Programming Bitcoin" teaches the mathematical foundations of Bitcoin, including finite fields, elliptic curves, and the secp256k1 curve used in Bitcoin. This implementation follows the book's structure, chapter by chapter, with each chapter containing exercises that build upon the previous ones.

Project Structure

The code is organized by chapters, mirroring the book's progression:

• src/ch01/ - Finite Fields

  • Basic field arithmetic operations
  • FieldElement struct with addition, subtraction, multiplication, division, and exponentiation

• src/ch02/ - Elliptic Curves over Finite Fields

  • Point operations on elliptic curves
  • Point addition and scalar multiplication

• src/ch03/ - Elliptic Curves over secp256k1

  • Implementation of the secp256k1 curve used in Bitcoin
  • Large number handling with BigUint/BigInt for cryptographic operations

• src/ch04/ - Serialization

  • Serialization of secp256k1 points and signatures
  • SEC (Standards for Efficient Cryptography) format implementation

• src/ch05/ - Transactions

  • Bitcoin transaction parsing and structure
  • Variable-length integer encoding/decoding
  • Transaction input/output handling

• src/lib.rs - Library entry point

• src/main.rs - Executable entry point

• tests/ - Integration tests for each chapter

Dependencies

This project uses the following Rust crates:

• num-bigint and num-traits - Arbitrary-precision arithmetic for large numbers
• secp256k1 - secp256k1 elliptic curve cryptography library
• hex - Hexadecimal encoding/decoding
• serde and serde_json - Serialization/deserialization
• sha2 - SHA-256 hashing
• hmac - HMAC (Hash-based Message Authentication Code)
• rand - Random number generation
• bs58 - Base58 encoding (used in Bitcoin addresses)
• ripemd - RIPEMD-160 hashing
• reqwest - HTTP client for API interactions
• tokio - Asynchronous runtime
• dotenvy - Environment variable loading

Building and Running

Prerequisites

• Rust 1.70+ (install via rustup)

Build

cargo build

Run Tests

cargo test

Run the Executable

cargo run

CI/CD

This project uses GitHub Actions for continuous integration and deployment. The CI pipeline includes:

• Automated Testing: Runs cargo test on multiple Rust versions and operating systems
• Code Formatting: Ensures code follows Rust formatting standards with cargo fmt
• Linting: Checks for common issues with cargo clippy
• Security Auditing: Scans dependencies for vulnerabilities

CI Configuration

The CI workflow is defined in .github/workflows/ci.yml and includes jobs for:

• Building and testing on Linux, macOS, and Windows
• Code quality checks
• Dependency auditing

To set up CI/CD locally or contribute:

1. Ensure your code passes cargo fmt and cargo clippy
2. Run the full test suite with cargo test
3. Push to a branch to trigger CI checks

Key Concepts Implemented

• Finite Fields: Custom FieldElement struct supporting modular arithmetic
• Elliptic Curves: Point addition, doubling, and scalar multiplication
• secp256k1: Bitcoin's elliptic curve with proper large number handling
• Serialization: SEC format for public key compression and uncompressed formats
• Digital Signatures: ECDSA signature creation and verification
• Transactions: Bitcoin transaction structure, parsing, and validation
• Variable-Length Integers: CompactSize encoding for Bitcoin protocol
• Cryptographic Primitives: Modular inverse, exponentiation, and reduction

Learning Goals

This implementation serves as a learning tool to:

• Understand Bitcoin's mathematical foundations from finite fields to transaction validation
• Practice Rust programming with complex mathematical concepts and cryptography
• Implement cryptographic algorithms and protocols from scratch
• Compare Python and Rust approaches to the same problems
• Learn Bitcoin's serialization formats and transaction structure
• Gain experience with real-world cryptographic libraries and best practices

References

• Programming Bitcoin by Jimmy Song
• Bitcoin Wiki - Elliptic Curve Digital Signature Algorithm
• secp256k1 specification

License

This project is for educational purposes. The original book's code and concepts belong to Jimmy Song and O'Reilly Media. /home/wilfrid_k/projects/boss_challenge/programming_bitcoin/README.md