Mullvad VPN desktop and mobile app

Welcome to the Mullvad VPN client app. This repository contains all the source code for the desktop and mobile versions of the app. For desktop this includes the system service/daemon (mullvad-daemon), a graphical user interface (GUI) and a command line interface (CLI). The Android app uses the same backing system service for the tunnel and security but has a dedicated frontend in android/. iOS consists of a completely standalone implementation that resides in ios/.

Releases

There are built and signed releases for macOS, Windows, Linux and Android available on our website and on Github. The Android app is also available on Google Play and F-Droid and the iOS version on App Store.

You can find our code signing keys as well as instructions for how to cryptographically verify your download on Mullvad's Open Source page.

Platform/OS support

These are the operating systems and their versions that the app officially supports. It might work on many more versions, but we don't test for those and can't guarantee the quality or security.

On Linux we test using the Gnome desktop environment. The app should, and probably does work in other DEs, but we don't regularly test those.

Features

Here is a table containing the features of the app across platforms. This reflects the current state of latest master, not necessarily any existing release.

* The local network is always accessible on iOS with the current implementation

Security and anonymity

This app is a privacy preserving VPN client. As such it goes to great lengths to stop traffic leaks. And basically all settings default to the more secure/private option. The user has to explicitly allow more loose rules if desired. See the dedicated security document for details on what the app blocks and allows, as well as how it does it.

Checking out the code

This repository contains submodules needed for building the app. However, some of those submodules also have further submodules that are quite large and not needed to build the app. So unless you want the source code for OpenSSL, OpenVPN and a few other projects you should avoid a recursive clone of the repository. Instead clone the repository normally and then get one level of submodules:

git clone https://github.com/mullvad/mullvadvpn-app.git
cd mullvadvpn-app
git submodule update --init

We sign every commit on the master branch as well as our release tags. If you would like to verify your checkout, you can find our developer keys on Mullvad's Open Source page.

Binaries submodule

This repository has a git submodule at dist-assets/binaries. This submodule contains binaries and build scripts for third party code we need to bundle with the app. Such as OpenVPN, Shadowsocks etc.

This submodule conforms to the same integrity/security standards as this repository. Every merge commit should be signed. And this main repository should only ever point to a signed merge commit of the binaries submodule.

See the binaries submodule's README for more details about that repository.

Install toolchains and dependencies

Follow the instructions for your platform, and then the All platforms instructions.

These instructions are probably not complete. If you find something more that needs installing on your platform please submit an issue or a pull request.

Windows

The host has to have the following installed:

• Microsoft's Build Tools for Visual Studio 2019 (a regular installation of Visual Studio 2019 Community edition works as well).

• Windows 10 SDK.

• msbuild.exe available in %PATH%. If you installed Visual Studio Community edition, the binary can be found under:

  C:\Program Files (x86)\Microsoft Visual Studio\2019\Community\MSBuild\Current\Bin\amd64
  

• bash installed as well as a few base unix utilities, including sed and tail. The environment coming with Git for Windows works fine.

• gcc for CGo.

Linux

Debian/Ubuntu

# For building the daemon
sudo apt install gcc libdbus-1-dev
# For building the installer
sudo apt install rpm

Fedora/RHEL

# For building the daemon
sudo dnf install dbus-devel
# For building the installer
sudo dnf install rpm-build

Android

These instructions are for building the app for Android under Linux.

Download and install the JDK

sudo apt install zip default-jdk

Download and install the SDK

The SDK should be placed in a separate directory, like for example ~/android or /opt/android. This directory should be exported as the $ANDROID_HOME environment variable.

cd /opt/android     # Or some other directory to place the Android SDK
export ANDROID_HOME=$PWD

wget https://dl.google.com/android/repository/commandlinetools-linux-6609375_latest.zip
unzip commandlinetools-linux-6609375_latest.zip
./tools/bin/sdkmanager "platforms;android-29" "build-tools;29.0.3" "platform-tools"

If sdkmanager fails to find the SDK root path, pass the option --sdk_root=$ANDROID_HOME to the command above.

Download and install the NDK

The NDK should be placed in a separate directory, which can be inside the $ANDROID_HOME or in a completely separate path. The extracted directory must be exported as the $ANDROID_NDK_HOME environment variable.

cd "$ANDROID_HOME"  # Or some other directory to place the Android NDK
wget https://dl.google.com/android/repository/android-ndk-r20b-linux-x86_64.zip
unzip android-ndk-r20b-linux-x86_64.zip

cd android-ndk-r20b
export ANDROID_NDK_HOME="$PWD"

Docker

Docker is required to build wireguard-go for Android. Follow the installation instructions for your distribution.

Configuring Rust

These steps has to be done after you have installed Rust in the section below:

Install the Rust Android target

Some environment variables must be exported so that some Rust dependencies can be cross-compiled correctly:

export NDK_TOOLCHAIN_DIR="$ANDROID_NDK_HOME/toolchains/llvm/prebuilt/linux-x86_64/bin"
export AR_aarch64_linux_android="$NDK_TOOLCHAIN_DIR/aarch64-linux-android-ar"
export AR_armv7_linux_androideabi="$NDK_TOOLCHAIN_DIR/arm-linux-androideabi-ar"
export AR_x86_64_linux_android="$NDK_TOOLCHAIN_DIR/x86_64-linux-android-ar"
export AR_i686_linux_android="$NDK_TOOLCHAIN_DIR/i686-linux-android-ar"
export CC_aarch64_linux_android="$NDK_TOOLCHAIN_DIR/aarch64-linux-android21-clang"
export CC_armv7_linux_androideabi="$NDK_TOOLCHAIN_DIR/armv7a-linux-androideabi21-clang"
export CC_x86_64_linux_android="$NDK_TOOLCHAIN_DIR/x86_64-linux-android21-clang"
export CC_i686_linux_android="$NDK_TOOLCHAIN_DIR/i686-linux-android21-clang"

rustup target add aarch64-linux-android armv7-linux-androideabi i686-linux-android x86_64-linux-android

Set up cargo to use the correct linker and archiver

This block assumes you installed everything under /opt/android, but you can install it wherever you want as long as the ANDROID_HOME variable is set accordingly.

Add to ~/.cargo/config.toml:

[target.aarch64-linux-android]
ar = "/opt/android/android-ndk-r20b/toolchains/llvm/prebuilt/linux-x86_64/bin/aarch64-linux-android-ar"
linker = "/opt/android/android-ndk-r20b/toolchains/llvm/prebuilt/linux-x86_64/bin/aarch64-linux-android21-clang"

[target.armv7-linux-androideabi]
ar = "/opt/android/android-ndk-r20b/toolchains/llvm/prebuilt/linux-x86_64/bin/arm-linux-androideabi-ar"
linker = "/opt/android/android-ndk-r20b/toolchains/llvm/prebuilt/linux-x86_64/bin/armv7a-linux-androideabi21-clang"

[target.x86_64-linux-android]
ar = "/opt/android/android-ndk-r20b/toolchains/llvm/prebuilt/linux-x86_64/bin/x86_64-linux-android-ar"
linker = "/opt/android/android-ndk-r20b/toolchains/llvm/prebuilt/linux-x86_64/bin/x86_64-linux-android21-clang"

[target.i686-linux-android]
ar = "/opt/android/android-ndk-r20b/toolchains/llvm/prebuilt/linux-x86_64/bin/i686-linux-android-ar"
linker = "/opt/android/android-ndk-r20b/toolchains/llvm/prebuilt/linux-x86_64/bin/i686-linux-android21-clang"

Signing key for release APKs (optional)

In order to build release APKs, they need to be signed. First, a signing key must be generated and stored in a keystore file. In the example below, the keystore file will be /home/user/app-keys.jks and will contain a key called release.

keytool -genkey -v -keystore /home/user/app-keys.jks -alias release -keyalg RSA -keysize 4096 -validity 10000

Fill in the requested information to generate the key and the keystore file. Suppose the file was protected by a password keystore-password and the key with a password key-password. This information should then be added to the android/keystore.properties file:

keyAlias = release
keyPassword = key-password
storeFile = /home/user/app-keys.jks
storePassword = keystore-password

All platforms

1. Make sure to use a recent version of bash. The default version in macOS (3.2.57) isn't supported.

2. Get the latest stable Rust toolchain via rustup.rs.

3. This can be skipped for Android builds.

   Get the latest version 16 release of Node.js and the latest version of npm. The Node.js version is specified in .nvmrc and can be installed by running the following from any directory within this repository:

   nvm install --latest-npm
   

   If installing Node.js manually then the latest version of npm can be installed by running:

   npm install -g npm
   

   macOS

   brew install node

   Linux

   Just download and unpack the node-v16.xxxx.tar.xz tarball and add its bin directory to your PATH.

   Windows

   Download the Node.js installer from the official website.

4. Install Go (ideally version 1.16) by following the official instructions. Newer versions may work too. Since cgo is being used, make sure to have a C compiler in your path. On Windows mingw's gcc compiler should work. gcc on most Linux distributions should work, and clang for MacOS.

Building and packaging the app

Desktop

The simplest way to build the entire app and generate an installer is to just run the build script. --dev-build is added to skip some release checks and signing of the binaries:

./build.sh --dev-build

This should produce an installer exe, pkg or rpm+deb file in the dist/ directory.

Building this requires at least 1GB of memory.

macOS

By default a universal app is built on macOS. To build specifically for x86_64 or ARM64 add --target x86_64-apple-darwin or --target aarch64-apple-darwin.

Apple ARM64 (aka Apple Silicon)

Due to inability to build the management interface proto files on ARM64 (see this issue) the Apple ARM64 build must be done in 2 stages:

1. Build management interface proto files on a non-ARM64 platform
2. Use the built proto files during the main build by setting the MANAGEMENT_INTERFACE_PROTO_BUILD_DIR environment variable to the path the proto files

To build the management interface proto files there is a script (execute it on a non-ARM64 platform):

cd gui/scripts
npm ci
./build-proto.sh

After that copy the files from gui/src/main/management_interface/ and gui/build/src/main/management_interface/ directories into a single directory on your Apple Silicon Mac, and set the value of MANAGEMENT_INTERFACE_PROTO_BUILD_DIR to that directory while running the main build.

Make sure that the version of Go on your Mac is 1.16 (the first version to add support for Apple Silicon) or newer.

Install protobuf by running:

brew install protobuf

When all is done run the main build. Assuming that you copied the proto files into /tmp/management_interface_proto directory, the build command will look as follows:

MANAGEMENT_INTERFACE_PROTO_BUILD_DIR=/tmp/management_interface_proto ./build.sh --dev-build

If you want to build each component individually, or run in development mode, read the following sections.

Android

Running the build-apk.sh script will build the necessary Rust daemon for all supported ABIs and build the final APK:

./build-apk.sh

You may pass a --dev-build to build the Rust daemon and the UI in debug mode and sign the APK with automatically generated debug keys:

./build-apk.sh --dev-build

If the above fails with an error related to compression, try allowing more memory to the JVM:

echo "org.gradle.jvmargs=-Xmx4608M" >> ~/.gradle/gradle.properties
./android/gradlew --stop

Building and running mullvad-daemon on desktop

1. Firstly, on MacOS and Linux, one should source env.sh to set the default environment variables.

   source env.sh

2. On Windows, make sure to start bash first (e.g., Git BASH). Then build the C++ libraries:

    ./build-windows-modules.sh --dev-build

3. Build the system daemon plus the other Rust tools and programs:

   cargo build

4. Copy the OpenVPN and Shadowsocks binaries, and our plugin for it, to the directory we will use as resource directory. If you want to use any other directory, you would need to copy even more files.

   cp dist-assets/binaries/<platform>/{openvpn, sslocal}[.exe] dist-assets/
   cp target/debug/*talpid_openvpn_plugin* dist-assets/

5. On Windows, also copy wintun.dll to the build directory:

   cp dist-assets/binaries/x86_64-pc-windows-msvc/wintun.dll target/debug/

6. On Windows, the daemon must be run as the SYSTEM user. You can use PsExec to launch an elevated bash instance before starting the daemon in it:

   psexec64 -i -s bash.exe
   

7. Run the daemon with verbose logging (from the root directory of the project):

   sudo MULLVAD_RESOURCE_DIR="./dist-assets" ./target/debug/mullvad-daemon -vv

   Leave out sudo on Windows. The daemon must run as root since it modifies the firewall and sets up virtual network interfaces etc.

Environment variables controlling the execution

• TALPID_FIREWALL_DEBUG - Helps debugging the firewall. Does different things depending on platform:

  • Linux: Set to "1" to add packet counters to all firewall rules.
  • macOS: Makes rules log the packets they match to the pflog0 interface.
    • Set to "all" to add logging to all rules.
    • Set to "pass" to add logging to rules allowing packets.
    • Set to "drop" to add logging to rules blocking packets.

• TALPID_FIREWALL_DONT_SET_SRC_VALID_MARK - Forces the daemon to not set src_valid_mark config on Linux. The kernel config option is set because otherwise strict reverse path filtering may prevent relay traffic from reaching the daemon. If rp_filter is set to 1 on the interface that will be receiving relay traffic, and src_valid_mark is not set to 1, the daemon will not be able to receive relay traffic.

• TALPID_DNS_MODULE - Allows changing the method that will be used for DNS configuration on Linux. By default this is automatically detected, but you can set it to one of the options below to choose a specific method:

  • "static-file": change the /etc/resolv.conf file directly
  • "resolvconf": use the resolvconf program
  • "systemd": use systemd's resolved service through DBus
  • "network-manager": use NetworkManager service through DBus

• TALPID_FORCE_USERSPACE_WIREGUARD - Forces the daemon to use the userspace implementation of WireGuard on Linux.

• TALPID_DNS_CACHE_POLICY - On Windows, this changes how DNS is configured:

  • 1: The default. This sets a global list of DNS servers that dnscache will use instead of the servers specified on each interface.
  • 0: Only set DNS servers on the tunnel interface. This will misbehave if local custom DNS servers are used.

• TALPID_DISABLE_OFFLINE_MONITOR - Forces the daemon to always assume the host is online.

• MULLVAD_MANAGEMENT_SOCKET_GROUP - On Linux and macOS, this restricts access to the management interface UDS socket to users in the specified group. This means that only users in that group can use the CLI and GUI. By default, everyone has access to the socket.

Dev builds only

• MULLVAD_API_HOST - Set the hostname to use in API requests. E.g. api.mullvad.net.

• MULLVAD_API_ADDR - Set the IP address and port to use in API requests. E.g. 10.10.1.2:443.

Setting environment variable

• On Windows, one can use setx from an elevated shell, like so

  setx TALPID_DISABLE_OFFLINE 1 /m

  For the change to take effect, one must restart the daemon

  sc.exe stop mullvadvpn
  sc.exe start mullvadvpn

• On Linux, one should edit the systemd unit file via systemctl edit mullvad-daemon.service and edit it like so

  [Service]
  Environment="TALPID_DISABLE_OFFLINE_MONITOR=1"
  

  For the change to take effect, one must restart the daemon

  sudo systemctl restart mullvad-daemon

• On macOS, one can use launchctl like so

  sudo launchctl setenv TALPID_DISABLE_OFFLINE_MONITOR 1

  For the change to take effect, one must restart the daemon

  launchctl unload -w /Library/LaunchDaemons/net.mullvad.daemon.plist
  launchctl load -w /Library/LaunchDaemons/net.mullvad.daemon.plist

Building and running the desktop Electron GUI app

1. Go to the gui directory

   cd gui

2. Install all the JavaScript dependencies by running:

   npm install

3. Start the GUI in development mode by running:

   npm run develop

If you change any javascript file while the development mode is running it will automatically transpile and reload the file so that the changes are visible almost immediately.

Please note that the GUI needs a running daemon to connect to in order to work. See Building and running mullvad-daemon for instruction on how to do that before starting the GUI.

Supported environment variables

1. MULLVAD_PATH - Allows changing the path to the folder with the mullvad-problem-report tool when running in development mode. Defaults to: <repo>/target/debug/.
2. MULLVAD_DISABLE_UPDATE_NOTIFICATION - If set to 1, GUI notification will be disabled when an update is available.

Making a release

When making a real release there are a couple of steps to follow. <VERSION> here will denote the version of the app you are going to release. For example 2018.3-beta1 or 2018.4.

1. Follow the Install toolchains and dependencies steps if you have not already completed them.

2. Make sure the CHANGELOG.md is up to date and has all the changes present in this release. Also change the [Unreleased] header into [<VERSION>] - <DATE> and add a new [Unreleased] header at the top. Push this, get it reviewed and merged.

3. Run ./prepare_release.sh <VERSION>. This will do the following for you:

   1. Check if your repository is in a sane state and the given version has the correct format
   2. Update package.json with the new version and commit that
   3. Add a signed tag to the current commit with the release version in it

   Please verify that the script did the right thing before you push the commit and tag it created.

4. When building for Windows or macOS, the following environment variables must be set:

   • CSC_LINK - The path to the certificate used for code signing.

     • Windows: A .pfx certificate.
     • macOS: A .p12 certificate file with the Apple application signing keys. This file must contain both the "Developer ID Application" and the "Developer ID Installer" certificates + private keys.

   • CSC_KEY_PASSWORD - The password to the file given in CSC_LINK. If this is not set then build.sh will prompt you for it. If you set it yourself, make sure to define it in such a way that it's not stored in your bash history:

     export HISTCONTROL=ignorespace
     export CSC_KEY_PASSWORD='my secret'

   • macOS only:

     • NOTARIZE_APPLE_ID - The AppleId to use when notarizing the app. Only needed on release builds

     • NOTARIZE_APPLE_ID_PASSWORD - The AppleId password for the account in NOTARIZE_APPLE_ID. Don't use the real AppleId password! Instead create an app specific password and add that to your keyring. See this documentation: https://github.com/electron/electron-notarize#safety-when-using-appleidpassword

       Summary:

       1. Generate app specific password on Apple's AppleId management portal.
       2. Run security add-generic-password -a "<apple_id>" -w <app_specific_password> -s "something_something"
       3. Set NOTARIZE_APPLE_ID_PASSWORD="@keychain:something_something".

5. Run ./build.sh on each computer/platform where you want to create a release artifact. This will do the following for you:

   1. Update relays.json with the latest relays
   2. Compile and package the app into a distributable artifact for your platform.

   Please pay attention to the output at the end of the script and make sure the version it says it built matches what you want to release.

Command line tools for Electron GUI app development

• $ npm run develop - develop app with live-reload enabled
• $ npm run lint - lint code
• $ npm run pack:<OS> - prepare app for distribution for your platform. Where <OS> can be linux, mac or win
• $ npm test - run tests

Tray icon on Linux

The requirements for displaying a tray icon varies between different desktop environments. If the tray icon doesn't appear, try installing one of these packages:

• libappindicator3-1
• libappindicator1
• libappindicator

If you're using GNOME, try installing one of these GNOME Shell extensions:

• TopIconsFix
• TopIcons Plus

Repository structure

Electron GUI app and electron-builder packaging assets

• gui/
  • assets/ - Graphical assets and stylesheets
  • src/
    • main/
      • index.ts - Entry file for the main process
    • renderer/
      • app.tsx - Entry file for the renderer process
      • routes.tsx - Routes configurator
      • transitions.ts - Transition rules between views
    • config.json - App color definitions and URLs to external resources
  • tasks/ - Gulp tasks used to build app and watch for changes during development
    • distribution.js - Configuration for electron-builder
  • test/ - Electron GUI tests
• dist-assets/ - Icons, binaries and other files used when creating the distributables
  • binaries/ - Git submodule containing binaries bundled with the app. For example the statically linked OpenVPN binary. See the README in the submodule for details
  • linux/ - Scripts and configuration files for the deb and rpm artifacts
  • pkg-scripts/ - Scripts bundled with and executed by the macOS pkg installer
  • windows/ - Windows NSIS installer configuration and assets
  • ca.crt - The Mullvad relay server root CA. Bundled with the app and only OpenVPN relays signed by this CA are trusted

Building, testing and misc

• build-windows-modules.sh - Compiles the C++ libraries needed on Windows
• build.sh - Sanity checks the working directory state and then builds release artifacts for the app

Mullvad Daemon

The daemon is implemented in Rust and is implemented in several crates. The main, or top level, crate that builds the final daemon binary is mullvad-daemon which then depend on the others.

In general one can look at the daemon as split into two parts, the crates starting with talpid and the crates starting with mullvad. The talpid crates are supposed to be completely unrelated to Mullvad specific things. A talpid crate is not allowed to know anything about the API through which the daemon fetch Mullvad account details or download VPN server lists for example. The talpid components should be viewed as a generic VPN client with extra privacy and anonymity preserving features. The crates having mullvad in their name on the other hand make use of the talpid components to build a secure and Mullvad specific VPN client.

• Cargo.toml - Main Rust workspace definition. See this file for which folders here are daemon Rust crates.
• mullvad-daemon/ - Main Rust crate building the daemon binary.
• talpid-core/ - Main crate of the VPN client implementation itself. Completely Mullvad agnostic privacy preserving VPN client library.

Vocabulary

Explanations for some common words used in the documentation and code in this repository.

• App - This entire product (everything in this repository) is the "Mullvad VPN App", or App for short.
  • Daemon - Refers to the mullvad-daemon Rust program. This headless program exposes a management interface that can be used to control the daemon
  • Frontend - Term used for any program or component that connects to the daemon management interface and allows a user to control the daemon.
    • GUI - The Electron + React program that is a graphical frontend for the Mullvad VPN App.
    • CLI - The Rust program named mullvad that is a terminal based frontend for the Mullvad VPN app.

File paths used by Mullvad VPN app

A list of file paths written to and read from by the various components of the Mullvad VPN app

Daemon

On Windows, when a process runs as a system service the variable %LOCALAPPDATA% expands to C:\Windows\system32\config\systemprofile\AppData\Local.

All directory paths are defined in, and fetched from, the mullvad-paths crate.

Settings

The settings directory can be changed by setting the MULLVAD_SETTINGS_DIR environment variable.

Logs

The log directory can be changed by setting the MULLVAD_LOG_DIR environment variable.

Cache

The cache directory can be changed by setting the MULLVAD_CACHE_DIR environment variable.

RPC address file

The full path to the RPC address file can be changed by setting the MULLVAD_RPC_SOCKET_PATH environment variable.

GUI

The GUI has a specific settings file that is configured for each user. The path is set in the gui/packages/desktop/main/gui-settings.ts file.

Icons

Icons such as the logo and menubar icons are automatically generated. The source files are:

Generate desktop icon by running

gui/scripts/build-logo-icons.sh

Generate android icons

android/generate-pngs.sh

Generate iOS icon and assets

ios/convert-assets.rb --app-icon
ios/convert-assets.rb --import-desktop-assets
ios/convert-assets.rb --additional-assets

Generate desktop menubar icons

gui/scripts/build-menubar-icons.sh

The menubar icons are described futher here.

Locales and translations

Instructions for how to handle locales and translations are found here.

For instructions specific to the Android app, see here.

Audits, pentests and external security reviews

Mullvad has used external pentesting companies to carry out security audits of this VPN app. Read more about them in the audits readme.

License

Copyright (C) 2021 Mullvad VPN AB

This program is free software: you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation, either version 3 of the License, or (at your option) any later version.

For the full license agreement, see the LICENSE.md file

The source code for the iOS app is GPL-3 licensed like everything else in this repository. But the distributed app on the Apple App Store is not GPL licensed, it falls under the Apple App Store EULA.