# Legal, Licensing, and Third-Party Material

> What is licensed how, what we may redistribute, and how we stay clean while
> doing adversarial interoperability.

## 1. The project's licenses

| Component | License | Rationale |
|---|---|---|
| `kernel/**` (e.g. `open-iov-vfio.ko`) | **GPL-2.0** (`MODULE_LICENSE("GPL v2")`) | The Linux kernel exports the interfaces we need (VFIO, mdev, IOMMU, DMA) under `EXPORT_SYMBOL_GPL`. GPL-2.0 is the legally correct choice. |
| `userspace/**`, `tools/**`, `scripts/**`, `config/**`, `docs/**` | **BSD-3-Clause** | Maximizes reuse and adoption — the project's mission. |
| Third-party submodules and imported trees | their own licenses | Not relicensed; used under their terms. |

Per-file `SPDX-License-Identifier` headers always govern.

The split is deliberate: the kernel side gets a clean legal footing; everything
vendor-facing, embeddable and reusable stays permissive. Commercial adoption is
welcome and requires no license fee.

## 2. How we learn the interfaces

Open-IOV is built by **reverse engineering and decompilation**: we study the
behaviour of vendor drivers and firmware — in VMs, on hardware, and by
disassembling published firmware images and analysed binaries — and we
reimplement the interfaces we discover. What this project publishes is our
own work: behaviour descriptions, numeric identifiers, layouts, emulation
code, and the evidence behind each observation.

In this repository you will find:

* **GSP firmware images** (`firmware/**/*.fwimage.bin`) — fetched from public
  distribution channels (e.g. `linux-firmware`); used to understand and
  emulate the firmware interface.
* **Decompiled firmware artifacts** (`firmware/**/decompiled/`) — our own
  analysis output; kept for study and cited in the wiki.
* **Reformatted interface tables** — IDs, structures and message layouts that
  we derived, published in `wiki/` and in this documentation tree.

**Our rule:** publish *our work product* (facts, layouts, behaviours, code and
evidence). Do not copy third-party source or documentation into this project,
do not point readers at material we cannot redistribute, and do not
redistribute third-party binaries as project content beyond what their terms
allow.

## 3. Adversarial interoperability and the law

We implement the *interface contract* so that unmodified NVIDIA software can
talk to our device. We do not:

* copy NVIDIA driver code into our kernel module,
* patch NVIDIA drivers or firmware,
* defeat licensing for NVIDIA's own products (our device is our device; no
  impersonation of a licensed product identity).

Where interoperability requires knowledge of structures and constants, we
obtain them from publicly distributed headers and from observation of the
unmodified guest in a lab, and we document the evidence. This is the same
discipline used by other interoperable implementations of closed interfaces.

If you believe a specific artifact in this repository is improperly included,
open an issue: we would rather over-comply than argue.

## 4. Contributions

* Inbound = outbound: contributions to BSD-3-Clause files are BSD-3-Clause;
  contributions to GPL-2.0 files are GPL-2.0.
* By contributing you confirm you have the right to do so and that the
  contribution does not contain third-party material under incompatible terms.
* Write original code. Describe behaviour, cite the evidence, and reimplement
  interfaces from observation rather than copying anyone's source.
* Do not commit firmware or ISO images unless they are explicitly permitted and
  listed in `.gitattributes`/LFS policy.

## 5. Export, safety and platform notes

* GPU firmware and drivers may be subject to export regulations in your
  jurisdiction; users are responsible for compliance.
* Security-sensitive deployments should follow the security evaluation doc and
  the platform's attestation mechanisms (e.g. TrenchBoot).
* Nothing in this project's licensing changes the licenses of the host
  distribution's NVIDIA driver, the guest's driver, or any hypervisor.