<div align="center">

  <img src="logo-horizontal.svg" alt="Konduit" height="52"/>

  <br/><br/>

  **TCP-Native VPN. Works Where UDP Doesn't.**

  [![License: Proprietary](https://img.shields.io/badge/license-Proprietary-red)](LICENSE)
  [![Platform](https://img.shields.io/badge/platform-Linux%20%7C%20Windows%20%7C%20Android-lightgrey)]()
  [![Status](https://img.shields.io/badge/status-Beta-orange)]()

</div>

---

Konduit is a modern VPN built around a single principle: **TCP transport that works when UDP is blocked.**

WireGuard is excellent — until your ISP throttles or blocks UDP. Konduit solves that without the complexity of OpenVPN or the fragility of UDP-wrapping hacks. It runs fully in userspace, requires no elevated privileges, and gets out of your way.

## Why Konduit?

Most VPNs treat TCP as a fallback. Konduit is designed for TCP from the ground up, which means:

- No HEAD-OF-LINE blocking from tunneling UDP into TCP
- Reliable behaviour on restrictive corporate and mobile networks
- WireGuard-level simplicity without the UDP dependency

## Features

- **TCP-native protocol** — designed for TCP, not retrofitted
- **Server-controlled routing** — administrators enforce routing policy; clients cannot bypass it
- **Userspace implementation** — no kernel modules, no root required
- **Hot config reload** — update server configuration without dropping connections
- **QR code provisioning** — scan once, connect instantly
- **Cross-platform** — Linux, Windows, Android (macOS and iOS coming soon)
- **Modern cryptography** — X25519 key exchange, ChaCha20-Poly1305 data channel
- **SOCKS5 chaining** — egress-dial (`use_proxy`) to reach the server through your own proxy, or a post-tunnel listener (`listen_socks`) for per-app routing — see [SOCKS Modes](docs/socks-modes.md)
- **Memory safe** — written entirely in Rust

## Download

Releases are published on the [Releases](../../releases) page. Each release includes:

| Artifact | Platform | Purpose |
|---|---|---|
| `konduit-server-*-linux-x86_64` | Linux | VPN server |
| `konduit-*-linux-x86_64` | Linux | CLI client |
| `konduit-ctl-*-linux-x86_64` | Linux | Server provisioning tool |
| `Konduit-*-x86_64.AppImage` | Linux | GUI client (AppImage) |
| `konduit-cli-*-windows-x86_64.zip` | Windows | CLI client + wintun.dll |
| `konduit-gui-*-windows-x86_64.zip` | Windows | GUI client |
| `konduit-*-android.aab` | Android | Android app (sideload via bundletool) |

### Linux (CLI)

```bash
# Download konduit and konduit-ctl from the Releases page, then:
chmod +x konduit konduit-ctl

# Bootstrap a server
echo "your secret mantra" | ./konduit-ctl bootstrap -l vpn.example.com:443 -p -

# Connect a client
./konduit connect --config client.toml
```

### Linux (GUI)

Download the `.AppImage`, make it executable, and run it:

```bash
chmod +x Konduit-*-x86_64.AppImage
./Konduit-*-x86_64.AppImage
```

### Windows

Extract the zip and run `konduit.exe` (CLI) or `Konduit.exe` (GUI). `wintun.dll` must remain alongside the executable.

### Android

Download from [Google Play](https://play.google.com/store/apps/details?id=eu.k_ops.konduit) or sideload the `.aab` using [bundletool](https://github.com/google/bundletool).

### macOS · iOS

Coming soon.

## Setup

**GUI clients**
- [Linux GUI Quickstart](docs/gui-quickstart-linux.md) — AppImage, privileges, autostart
- [Windows GUI Quickstart](docs/gui-quickstart-windows.md) — extract, UAC, WinTun, autostart

**CLI & server**
- [Client Quickstart](docs/client-quickstart.md) — download, configure, connect, run as a systemd service
- [Server Quickstart](docs/server-quickstart.md) — install, provision, NAT setup for iptables and firewalld
- [SOCKS5 Modes](docs/socks-modes.md) — reach the server through a proxy, or expose a local SOCKS5 listener
- [Connection Tuning](docs/connection-tuning.md) — opt-in connection pooling for unstable links
- [systemd units](docs/systemd/) — service files for konduit-server, konduit (client), and konduit-admin-ui

## Architecture

```
Flutter UI (Dart)
      │
flutter_rust_bridge (FFI)
      │
Konduit engine (Rust)
      ├── TUN device (userspace)
      ├── TCP tunnel protocol
      ├── Key exchange (X25519)
      └── Route manager
```

| Layer | Technology |
|---|---|
| UI | Flutter / Dart |
| Core engine | Rust (Tokio async) |
| FFI bridge | flutter_rust_bridge |
| Cryptography | ring / rustls |
| TUN device | tun crate (userspace) |

## Openness Model

The [`konduit-platform`](./konduit-platform) crate is published here for transparency and security audit. It contains the cryptographic primitives, connection statistics, and platform networking layer (TUN device, DNS, routes) — everything an auditor needs to verify what runs on your machine. It is licensed under the [PolyForm Noncommercial License 1.0.0](LICENSE) — free to read, study, and use for noncommercial purposes.

The VPN server and management UI are proprietary. Source review under NDA is available for enterprise partners.

## Security

**No UDP dependency:** Konduit does not require UDP at any layer.

**Key storage:** Private keys are stored in the OS secure enclave on every platform (iOS Keychain, macOS Keychain, Android Keystore). They are never written to disk in plaintext.

## Support

**Bug reports:** Use the in-app reporting feature or open an issue in this repository.

**Security vulnerabilities:** Do not open a public issue. Contact the maintainer directly at the address shown in the application's About screen.

**Contributing:** Core development is handled internally. We do not currently accept external pull requests.

---

## About

Created by **Eugen Kaparulin**.  
Official binaries distributed by **[K-Ops Oy](https://k-ops.eu)**.

© Eugen Kaparulin. All rights reserved.  
[`konduit-platform`](./konduit-platform) is published under the [PolyForm Noncommercial License 1.0.0](LICENSE).  
All other parts of Konduit are proprietary.  
[Privacy Policy](docs/privacy-policy.md)