Lan Mouse

Lan Mouse is a cross-platform mouse and keyboard sharing software similar to universal-control on Apple devices. It allows for using multiple PCs via a single set of mouse and keyboard. This is also known as a Software KVM switch.

Goal of this project is to be an open-source alternative to proprietary tools like Synergy 2/3, Share Mouse and other open source tools like Deskflow or Input Leap (Synergy fork).

Focus lies on performance, ease of use and a maintainable implementation that can be expanded to support additional backends for e.g. Android, iOS, ... in the future.

blazingly fast™ because it's written in rust.

• Now with a gtk frontend

Encryption

Lan Mouse encrypts all network traffic using the DTLS implementation provided by WebRTC.rs. There are currently no mitigations in place for timing side-channel attacks.

OS Support

Most current desktop environments and operating systems are fully supported, this includes - GNOME >= 45 - KDE Plasma >= 6.1 - Most wlroots based compositors, including Sway (>= 1.8), Hyprland and Wayfire - Windows - MacOS

Caveats / Known Issues

[!Important] - X11 currently only has support for input emulation, i.e. can only be used on the receiving end.

• Sway / wlroots: Wlroots based compositors without libei support on the receiving end currently do not handle modifier events on the client side. This results in CTRL / SHIFT / ALT / SUPER keys not working with a sending device that is NOT using the layer-shell backend

• Wayfire: If you are using Wayfire, make sure to use a recent version (must be newer than October 23rd) and add shortcuts-inhibit to the list of plugins in your wayfire config! Otherwise input capture will not work.

• Windows: The mouse cursor will be invisible when sending input to a Windows system if there is no real mouse connected to the machine.

For more detailed information about os support see Detailed OS Support

Android & IOS

A proof of concept for an Android / IOS Application by rohitsangwan01 can be found here. It can be used as a remote control for any device supported by Lan Mouse.

Installation

pacman -S lan-mouse

paru -S lan-mouse-git

dnf install lan-mouse

winget install lan-mouse

# install lan-mouse (replace path/to/ with the correct path)
sudo cp path/to/lan-mouse /usr/local/bin/

# install app icon
sudo mkdir -p /usr/local/share/icons/hicolor/scalable/apps
sudo cp lan-mouse-gtk/resources/de.feschber.LanMouse.svg /usr/local/share/icons/hicolor/scalable/apps

# update icon cache
gtk-update-icon-cache /usr/local/share/icons/hicolor/

# install desktop entry
sudo mkdir -p /usr/local/share/applications
sudo cp de.feschber.LanMouse.desktop /usr/local/share/applications

# when using firewalld: install firewall rule
sudo cp firewall/lan-mouse.xml /etc/firewalld/services
# -> enable the service in firewalld settings

# compile in release mode
cargo build --release

# install lan-mouse
sudo cp target/release/lan-mouse /usr/local/bin/

# will end up in ~/.cargo/bin
cargo install lan-mouse

# you can find the executable in result/bin/lan-mouse
nix-build

cargo build --no-default-features --features layer_shell_capture,wlroots_emulation

Development

Git pre-commit hook

This repository includes a local git hooks directory .githooks/ with a pre-commit script that enforces formatting, lints, and tests before allowing a commit. It is optional to enable it, but it will prevent you from committing code with failing unit tests or that needs clippy/fmt fixes. To enable the hook locally:

1. Make the hook executable:

chmod +x .githooks/pre-commit

2. Point git to the hooks directory (one-time per clone):

git config core.hooksPath .githooks

The pre-commit script runs cargo fmt --all (and fails if files were modified), cargo clippy --workspace --all-targets --all-features -- -D warnings, and cargo test --workspace --all-features.

Dependencies & Compiling from Source

# Install dependencies
brew install libadwaita pkg-config imagemagick
cargo install cargo-bundle
# Create the macOS icon file
scripts/makeicns.sh
# Create the .app bundle
cargo bundle
# Copy all dynamic libraries into the bundle, and update the bundle to find them there
scripts/copy-macos-dylib.sh

sudo apt install libadwaita-1-dev libgtk-4-dev libx11-dev libxtst-dev

sudo pacman -S libadwaita gtk libx11 libxtst

sudo dnf install libadwaita-devel libXtst-devel libX11-devel

nix-shell .

nix develop

# install chocolatey
Set-ExecutionPolicy Bypass -Scope Process -Force; iex ((New-Object System.Net.WebClient).DownloadString('https://community.chocolatey.org/install.ps1'))

# install gvsbuild dependencies
choco install python git msys2 visualstudio2022-workload-vctools

# install gvsbuild with python
python -m pip install --user pipx
python -m pipx ensurepath

pipx install gvsbuild

# build gtk + libadwaita
gvsbuild build gtk4 libadwaita librsvg adwaita-icon-theme

Usage

lan-mouse cli help

lan-mouse cli <cmd> help

lan-mouse daemon

Systemd Service

In order to start lan-mouse with a graphical session automatically, the systemd-service can be used:

Copy the file to ~/.config/systemd/user/ and enable the service:

cp service/lan-mouse.service ~/.config/systemd/user
systemctl --user daemon-reload
systemctl --user enable --now lan-mouse.service

[!Important] Make sure to point ExecStart=/usr/bin/lan-mouse daemon to the actual lan-mouse binary (in case it is not under /usr/bin, e.g. when installed manually.

Configuration

To automatically load clients on startup, the file $XDG_CONFIG_HOME/lan-mouse/config.toml is parsed. $XDG_CONFIG_HOME defaults to ~/.config/.

To create this file you can copy the following example config:

Example config

[!TIP] key symbols in the release bind are named according to their names in input-event/src/scancode.rs#L172. This is bound to change

# example configuration

# configure release bind
release_bind = [ "KeyA", "KeyS", "KeyD", "KeyF" ]

# optional port (defaults to 4242)
port = 4242

# list of authorized tls certificate fingerprints that
# are accepted for incoming traffic
[authorized_fingerprints]
"bc:05:ab:7a:a4:de:88:8c:2f:92:ac:bc:b8:49:b8:24:0d:44:b3:e6:a4:ef:d7:0b:6c:69:6d:77:53:0b:14:80" = "iridium"

# define a client on the right side with host name "iridium"
[[clients]]
# position (left | right | top | bottom)
position = "right"
# hostname
hostname = "iridium"
# activate this client immediately when lan-mouse is started
activate_on_startup = true
# optional list of (known) ip addresses
ips = ["192.168.178.156"]

# define a client on the left side with IP address 192.168.178.189
[[clients]]
position = "left"
# The hostname is optional: When no hostname is specified,
# at least one ip address needs to be specified.
hostname = "thorium"
# ips for ethernet and wifi
ips = ["192.168.178.189", "192.168.178.172"]
# optional port
port = 4242

Where left can be either left, right, top or bottom.

Roadmap

• [x] Graphical frontend (gtk + libadwaita)
• [x] respect xdg-config-home for config file location.
• [x] IP Address switching
• [x] Liveness tracking Automatically ungrab mouse when client unreachable
• [x] Liveness tracking: Automatically release keys, when server offline
• [x] MacOS KeyCode Translation
• [x] Libei Input Capture
• [x] MacOS Input Capture
• [x] Windows Input Capture
• [x] Encryption
• [ ] X11 Input Capture
• [ ] Latency measurement and visualization
• [ ] Bandwidth usage measurement and visualization
• [ ] Clipboard support

Detailed OS Support

In order to use a device for sending events, an input-capture backend is required, while receiving events requires a supported input-emulation and input-capture backend.

A suitable backend is chosen automatically based on the active desktop environment / compositor.

The following sections detail the emulation and capture backends provided by lan-mouse and their support in desktop environments / operating systems.

Input Emulation Support

• wlroots: This backend makes use of the wlr-virtual-pointer-unstable-v1 and virtual-keyboard-unstable-v1 protocols and is supported by most wlroots based compositors.
• libei: This backend uses libei and is supported by GNOME >= 45 or KDE Plasma >= 6.1.
• xdp: This backend uses the freedesktop remote-desktop-portal and is supported on GNOME and Plasma.
• x11: Backend for X11 sessions.
• windows: Backend for Windows.
• macos: Backend for MacOS.

Input Capture Support

• layer-shell: This backend creates a single pixel wide window on the edges of Displays to capture the cursor using the layer-shell protocol.
• libei: This backend uses libei and is supported by GNOME >= 45 or KDE Plasma >= 6.1.
• windows: Backend for input capture on Windows.
• macos: Backend for input capture on MacOS.
• x11: TODO (not yet supported)