This project will reach end-of-life on September 1st, 2022. On this date:
- This repository will be archived, making it read-only.
- The Google Group will be locked, but will remain publicly searchable.
- The project homepage, this README, and group will be updated to indicate that the project is end-of-life.
We will consider bug fixes from the community or support requests from existing customers up until this date.
Please make appropriate plans if you are using this library in production, e.g.:
- Dedicate personnel to maintaining your own internal copy of the library.
- Consider a commercial library such as the one offered by Step Function I/O.
You can read about this decision in these blog posts:
⚠️ This is a fork. The upstream project reached end-of-life in 2022. This fork extends the library with SAv2 and SAv5 (Secure Authentication) support for the outstation role, targeting embedded Linux platforms (BeagleBone Black + Comms Cape).
This fork adds a complete implementation of DNP3 Secure Authentication Version 2 and Version 5
(IEEE 1815-2010 and IEEE 1815-2012) for the outstation role. The implementation is
self-contained and does not break backward compatibility — SA is disabled by default
and activated via OutstationParams. The active version is selected at runtime via the SAMode enum.
The SA subsystem consists of four new modules:
| Module | File | Responsibility |
|---|---|---|
SAKeyManager |
SAKeyManager.h/.cpp |
Key Status (g120v5), Key Change (g120v6), AES Key Unwrap (RFC 3394), HMAC-SHA256 confirmation |
SAChallenger |
SAChallenger.h/.cpp |
Generates g120v1 Challenge, validates g120v2 Reply MAC |
SAResponder |
SAResponder.h/.cpp |
Stores session keys (CDK/MDK) per user, computes HMAC for authenticated responses |
Group120Parser / Group120Builder |
Group120Parser.h/.cpp, Group120Builder.h/.cpp |
Serializes/deserializes Group 120 Variations 1–6 |
OutstationContext intercepts critical function codes and initiates the
challenge-response exchange before execution per IEEE 1815-2012 Table 7-1.
// Select SA version: SAMode::NONE (default), SAMode::SAV2, SAMode::SAV5
config.outstation.params.saMode = SAMode::SAV5;
// SAv2: AES-128 Update Key — 16 bytes (128-bit)
config.outstation.params.saUpdateKey = {
0x4D, 0x56, 0x4B, 0xEA, 0x57, 0x15, 0xDD, 0x96,
0x59, 0xEF, 0x99, 0xA8, 0x95, 0xBB, 0x83, 0x0A,
// remaining 16 bytes are unused for SAv2 (zero-padded)
};
// SAv5: AES-256 Update Key — 32 bytes (256-bit)
config.outstation.params.saUpdateKey = {
0x4D, 0x56, 0x4B, 0xEA, 0x57, 0x15, 0xDD, 0x96,
0x59, 0xEF, 0x99, 0xA8, 0x95, 0xBB, 0x83, 0x0A,
0x4D, 0x56, 0x4B, 0xEA, 0x57, 0x15, 0xDD, 0x96,
0x59, 0xEF, 0x99, 0xA8, 0x95, 0xBB, 0x83, 0x0A,
};| SA Version | Master Software | Hardware |
|---|---|---|
| SAv5 | Zenon SCADA v15 by COPA-DATA | BeagleBone Black + Comms Cape (Debian 12) |
| SAv2 | Geo SCADA Expert 2025 by Schneider Electric | BeagleBone Black + Comms Cape (Debian 12) |
| none | FreyrSCADA v21 | BeagleBone Black + Comms Cape (Debian 12) |
MAC Algorithms
| Algorithm | Status |
|---|---|
| HMAC-SHA-1 truncated to 10 bytes | ✅ Tested |
| HMAC-SHA-1 truncated to 8 bytes | ✅ Tested |
| HMAC-SHA-256 truncated to 8 bytes | ✅ Tested |
| HMAC-SHA-256 truncated to 16 bytes | ✅ Tested |
| AES-GMAC | ⚪ Not testable (not supported by zenon) |
Key Wrap Algorithms
| Algorithm | Status |
|---|---|
| AES-128 Key Wrap (RFC 3394) | ✅ Tested |
| AES-256 Key Wrap (RFC 3394) | ✅ Tested |
Modes
| Feature | Status |
|---|---|
| Pre-challenge (normal) mode | ✅ Supported |
| Aggressive mode | ✅ Supported for SAv2 ❌ Not implemented for SAv5 |
SA support requires OpenSSL (≥ 1.1.0) linked at build time (libssl, libcrypto).
CMakeLists already includes OpenSSL detection for both Linux and Windows targets.
Opendnp3 is a portable, scalable, and rigorously tested implementation of the DNP3 protocol stack written in C++11. The library is designed for high-performance applications like many concurrent TCP sessions or huge device simulations. It also embeds with a small footprint on Linux.
| Branch | Build | Code coverage | Quality |
|---|---|---|---|
| release-2.x |  |
- | |
| develop |  |
 |
The documentation can be found on the project homepage.
If you want to help contribute to the official guide its in this repo.
Licensed under the terms of the Apache 2.0 License.
Copyright (c) 2010, 2011 Green Energy Corp
Copyright (c) 2013 - 2020 Step Function I/O LLC
Copyright (c) 2020 - 2022 Step Function I/O LLC
Copyright (c) 2010 - 2022 various contributors