GitHub - eddieoz/btcmesh: BTC Mesh Relay is designed to send Bitcoin payments via LoRa Meshtastic.

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BTC Mesh Relay

Description

BTC Mesh Relay is a project designed to enable the broadcasting of Bitcoin raw transactions by sending them as chunked hexadecimal strings via LoRa Meshtastic direct messages. A dedicated client script (btcmesh_cli.py) will be used for sending, and a relay device running btcmesh_server.py will reassemble these chunks, decode, validate, and then relay the complete transaction to a configured Bitcoin RPC node. This system is intended for scenarios with limited or censored internet access but where LoRa Meshtastic network availability exists.

This project is currently under development.

Features (Planned & In-Progress)

  • Meshtastic Communication: Initializes and manages communication with a Meshtastic device.
  • Transaction Chunking & Reassembly: Allows large Bitcoin transactions to be sent in smaller chunks over LoRa by btcmesh_cli.py and reassembled by btcmesh_server.py.
  • Payload Handling: Relay server reassembles hexadecimal chunks. The connected Bitcoin Core node performs full transaction validation upon broadcast attempt. (Advanced pre-broadcast decoding and validation capabilities on the relay server via core/transaction_parser.py are planned for future enhancements).
  • Basic Transaction Validation: Currently, the relay server relies on the connected Bitcoin Core node for most transaction validation. (More extensive pre-broadcast sanity checks on the relay are planned).
  • Bitcoin RPC Integration: Connects to a Bitcoin Core RPC node to broadcast the validated raw transaction.
  • Logging: Comprehensive logging for both server and client operations.
  • Client Script (btcmesh_cli.py): Implemented command-line tool (btcmesh_cli.py) for users to send raw transactions.
  • TOR: Optionally relay the transaction to a node running inside Tor network. (onion server)

Project Structure

btcmesh/
├── btcmesh_cli.py         # Client script
├── btcmesh_server.py      # Server/Relay script
├── core/                  # Core logic for the server/relay
│   ├── __init__.py
│   ├── config_loader.py   # For loading .env and other configurations
│   ├── logger_setup.py    # For setting up consistent logging
│   ├── transaction_parser.py # For decoding raw Bitcoin transactions (Planned)
│   ├── rpc_client.py      # For interacting with Bitcoin RPC
│   └── reassembler.py     # For reassembling chunked messages
├── project/               # Project planning documents
│   ├── tasks.txt
│   └── reference_materials.md
├── logs/                  # Directory for log files (created at runtime)
├── tests/                 # Unit and integration tests
├── .env.example           # Example environment variable configuration file
├── requirements.txt       # Python dependencies
└── README.md              # This file

(Refer to project/tasks.txt for detailed ongoing tasks and user stories.)

Setup Instructions

  1. Clone the Repository:

    git clone https://github.com/eddieoz/btcmesh.git
cd btcmesh

  2. Create and Activate Conda Environment: It's recommended to use a Conda environment. If you don't have Conda, please install it first.

    conda create -n btcmesh python=3.11
conda activate btcmesh

    Or use venv

    python -m venv env
source env/bin/activate

  3. Install Dependencies:

    pip install -r requirements.txt

  4. Configure Environment (.env): The application is configured using a .env file in the project root. Copy the example file to create your own configuration:

    Then, edit the .env file to set your specific configurations. For example:

    • MESHTASTIC_SERIAL_PORT: Specifies the serial port for your Meshtastic device (e.g., /dev/ttyUSB0, /dev/ttyACM0 on Linux, or COM3 on Windows). If this is not set or is commented out, the application will attempt to auto-detect the Meshtastic device. 
      # MESHTASTIC_SERIAL_PORT=/dev/your/meshtastic_port
    • Bitcoin RPC Node Details: Required for the relay server (btcmesh_server.py). 
      BITCOIN_RPC_HOST=your_bitcoin_node_host
BITCOIN_RPC_PORT=your_bitcoin_node_port # e.g., 8332 for mainnet
BITCOIN_RPC_USER=your_rpc_username
BITCOIN_RPC_PASSWORD=your_rpc_password
# Optional: For transaction reassembly timeout
# REASSEMBLY_TIMEOUT_SECONDS=120
    • Connecting via Tor: If you wish to connect to your Bitcoin RPC node via Tor, simply set the BITCOIN_RPC_HOST to your node's .onion address. The application will automatically detect this and manage the Tor connection using the Tor binary provided in the tor/ directory of this project. You do not need to have Tor installed or running separately on your system. 
      # Example for Tor connection:
# BITCOIN_RPC_HOST=yourbitcoinrpcnode.onion

    OBS The TOR binary supplied is part of the Debian package. REPLACE it to make it compatible with your distribution. DOWNLOAD TOR ```

  5. Meshtastic Device Setup:

    • Ensure you have a Meshtastic device connected to the machine where btcmesh_server.py will run (and another for the client when btcmesh_cli.py is used).
    • The Meshtastic Python library, by default, attempts to auto-detect your device. You can specify the serial port explicitly by setting MESHTASTIC_SERIAL_PORT in your .env file.
    • Ensure your Bitcoin Core node is configured to accept RPC connections.
    • Configure the RPC host, port, user, and password in your .env file (see step 4).
    • Tor Connectivity: If BITCOIN_RPC_HOST is a .onion address, the script will automatically attempt to establish a connection through Tor using the bundled Tor executable (./tor/tor). No separate Tor installation or configuration is required by the user.

Configuration

The primary method for configuration is via a .env file in the project root (see "Configure Environment (.env)" in Setup Instructions).

Key settings configurable in .env:

  • Meshtastic device serial port (MESHTASTIC_SERIAL_PORT).
  • Bitcoin RPC connection details (BITCOIN_RPC_HOST, BITCOIN_RPC_PORT, BITCOIN_RPC_USER, BITCOIN_RPC_PASSWORD). This includes the ability to use a .onion address for BITCOIN_RPC_HOST to automatically route traffic through Tor using the project's bundled Tor executable.
  • Transaction reassembly timeout (REASSEMBLY_TIMEOUT_SECONDS).

Running the Server (btcmesh_server.py)

Once set up and configured, you can run the BTC Mesh Relay server:

The server will initialize the Meshtastic interface, connect to the Bitcoin RPC node (if configured), and start listening for incoming messages.

Running the Client (btcmesh_cli.py)

The client script is used to send a raw Bitcoin transaction to a relay server.

python btcmesh_cli.py --destination <SERVER_NODE_ID> --tx <RAW_TRANSACTION_HEX>

Replace <SERVER_NODE_ID> with the Meshtastic node ID of the machine running btcmesh_server.py (e.g., !abcdef12) and <RAW_TRANSACTION_HEX> with the full raw transaction hex string you intend to broadcast.

Use python btcmesh_cli.py --help for more options, such as --dry-run to simulate sending without actually transmitting over LoRa.

Running Tests

To run the automated tests:

python -m unittest discover -s tests -p 'test_*.py'

Contributing

Contributions are welcome! Please refer to the project's issue tracker and development plan in project/tasks.txt. Follow TDD/BDD principles when adding new features or fixing bugs.

License

This project is licensed under the MIT License.

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