Yet Another opendnp3 fork -- an experimental fork of opendnp3, the de facto reference implementation of the DNP3 (IEEE-1815) protocol stack.

The upstream project reached end-of-life on September 1, 2022. This fork extends it with new protocol features, Python bindings, and modern CI.

For commercial or production use, consider Step Function I/O's DNP3 library — a modern, commercially supported Rust implementation with C, C++, Java, and .NET bindings.

Protocol — Master operations:

• Integrity / class / range / all-objects scans (periodic and on-demand)
• Select-before-operate and direct-operate commands (CROB, analog outputs)
• File transfer: read, write, delete, get info, directory listing, abort, authenticate
• Device attributes (Group 0)
• Analog input dead bands (Group 34)
• Freeze operations
• Cold/warm restart
• Time synchronization (LAN and serial modes)
• Link status check

Protocol — Outstation:

• Static and event reporting for all standard data types
• Unsolicited responses with configurable retries
• Command handling (select/operate, direct operate)
• File transfer handler interface
• Broadcast support
• Configurable event buffer and class assignment

Transports:

• TCP client and server
• Outstation TCP client mode (outstation connects to master)
• UDP
• Serial
• TLS (client and server, requires OpenSSL)

Bindings:

• Python (pybind11) — pip install yadnp3 (primary focus of this fork)
• Java (JNI) and .NET (C++/CLI) bindings exist from upstream but are not actively maintained in this fork

pip install yadnp3

import opendnp3

# Create a manager with 1 thread
manager = opendnp3.DNP3Manager(1)

# ... create channels, masters, outstations
# See python/tests/ for full examples

manager.Shutdown()

• CMake >= 3.11
• C++14 compiler (GCC, Clang, or MSVC 2015+)
• OpenSSL >= 1.1.1 (optional, for TLS)
• Python 3.9+ and pybind11 (optional, for Python bindings)

mkdir build && cd build
cmake .. -DDNP3_TLS=ON -DDNP3_TESTS=ON
cmake --build . --parallel $(nproc)
ctest --output-on-failure

docker build -f Dockerfile --build-arg PYTHON_VERSION=3.12 -t yadnp3-build .
docker create --name whl yadnp3-build
docker cp whl:/wheels/. ./dist/
docker rm whl
pip install dist/*.whl

yadnp3/
├── cpp/lib/              Core C++ library (~79k lines)
│   ├── include/opendnp3/ Public API headers
│   └── src/              Private implementation
├── cpp/tests/            Unit, integration, and interop tests
├── cpp/examples/         Example master/outstation applications
├── python/               Python bindings (pybind11, actively maintained)
├── java/                 Java bindings (JNI + Maven, upstream, not maintained)
├── dotnet/               .NET bindings (C++/CLI, upstream, not maintained)
├── generation/           Code generation (Scala/SBT)
├── Dockerfile            Linux wheel build
└── .github/workflows/    CI (build, test, wheel packaging)

Licensed under the Apache License 2.0.

Copyright (c) 2010-2011 Green Energy Corp Copyright (c) 2013-2022 Step Function I/O LLC Copyright (c) 2024-2026 f0rw4rd (yadnp3 fork) Copyright (c) 2010-2022 various contributors