This project provides reverse tethering over adb for Android: it
allows devices to use the internet connection of the computer they are plugged
on. It does not require any root access (neither on the device nor on the
computer). It works on GNU/Linux and Windows.
ret is a fork of Gnirehtet by Genymobile.
Currently, it relays TCP and UDP over IPv4 traffic, but it does not support IPv6 (yet?).
The Android application requires at least API 21 (Android 5.0).
ret talks to your devices through the adb server of your machine, with the
adb_client library. The adb program is only used to start that server
when no server runs yet.
No adb has to be installed: ret downloads the Android SDK platform
tools into its data directory (<AppData>\ret on Windows,
~/Library/Application Support/ret on macOS, ~/.local/share/ret on Linux)
and always starts the server from that copy. An adb installed on the system
is never used, and the download is kept, so it happens once. Only ADB
replaces the downloaded program, with one you choose.
Google's Linux download requires x86_64 and glibc. On Linux ARM64 or Alpine,
install your distribution's native adb and set ADB to its full path.
For example, use ADB=/usr/bin/adb ret run or ADB=/usr/bin/adb ret-ui.
The Alpine package already installs native adb.
While the tools download, ret shows a terminal progress bar with
the amount received and the percentage when the download size is known,
or a spinner when it is unknown, followed by the extraction status. ret-ui
shows the same progress in a banner, even when the logs are hidden, and shows
an error there if the download or installation fails.
ret-ui and ret autorun stop the ADB server they started when the window
closes or you press Ctrl+C. If an ADB server was already running, they reuse
it and leave it running on exit. Other CLI commands leave the server running
so commands such as ret start can keep the device connected after returning.
Make sure you enabled adb debugging on your device(s).
Download the appropriate files from the [latest release][latest].
The Linux tarball (ret-<version>-linux-<arch>.tar.gz) contains:
ret.apkretret-uiLICENSE
On Windows, run ret-setup-<version>-windows-<arch>.exe, choosing x86_64
for Intel/AMD or arm64 for Windows on ARM. The installer puts ret and
ret-ui on the user Path and installs the same ret.apk.
On macOS 13 or newer, download ret-<version>-macos-<arch>.dmg, choosing
x86_64 for Intel or arm64 for Apple Silicon. Open the disk image and drag
ret.app into Applications. The app includes the Android APK. These builds
are ad-hoc signed, not Developer ID signed or notarized. If macOS blocks the
first launch, review the app in System Settings > Privacy & Security and
choose Open Anyway only if you trust the downloaded release.
The matching macOS .tar.gz contains bin/ret, bin/ret-ui,
share/ret/ret.apk and LICENSE. Keep that directory layout when using the
command-line programs. Windows and macOS download their platform tools
automatically on first use.
Every release also publishes packages for Debian, Fedora, openSUSE, RHEL 9,
Arch and Alpine, an AppImage, and the Android application
(ret-v<version>.apk) on its own. Linux tarballs, debs, RPMs, AppImages and
Alpine packages support x86_64 and ARM64. Arch Linux packages are x86_64 only.
The release also includes the Apache-2.0 LICENSE.
Install the native package with your distribution's package manager so its library dependencies are installed too:
# Debian and Ubuntu
sudo apt install ./ret_<version>-1_amd64.deb
# Fedora
sudo dnf install ./ret-<version>-1-fedora-opensuse.x86_64.rpm
# RHEL 9 and its clones
sudo dnf install ./ret-<version>-1.el9-rhel9.x86_64.rpm
# openSUSE
sudo zypper install ./ret-<version>-1-fedora-opensuse.x86_64.rpm
# Arch Linux
sudo pacman -U ./ret-<version>-1-archlinux-x86_64.pkg.tar.zstReplace <version> with the release version. The examples above use x86_64.
For ARM64, choose arm64 in Debian package names and aarch64 in RPM,
Alpine, Linux tarball and AppImage names.
Alpine packages use a signing key for each release and architecture.
Download the matching ret-<version>-alpine-<arch>.rsa.pub from the same
release, install it under /etc/apk/keys/, then install
ret-<version>-r0-alpine-<arch>.apk with apk add. This Alpine package is
distinct from the Android APK named ret-v<version>.apk.
The Linux tarball and AppImage require glibc 2.31 or newer. The graphical
interface also needs the host's X11 or Wayland libraries, libxkbcommon and
EGL/OpenGL support. They do not include adb or graphics drivers. Make the
AppImage executable with chmod +x ret-<version>-linux-<arch>.AppImage before
running it. It uses its bundled Android APK unless RET_APK is already set.
Download SHA256SUMS.txt alongside your chosen assets to check their hashes:
sha256sum --ignore-missing -c SHA256SUMS.txtThis checks the files you downloaded, not the authenticity of their publisher.
The ret app is a different Android app from the Gnirehtet one, so ret does
not upgrade or control it. Uninstall the old app once:
adb uninstall com.genymobile.gnirehtet
The first ret run installs the new app and asks for the VPN permission again.
Note: On Windows, replace ./ret by ret in the following commands.
The application has no UI, and is intended to be controlled from the computer only.
If you want to activate reverse tethering for exactly one device, just execute:
./ret run
Reverse tethering remains active until you press Ctrl+C.
On Windows, for convenience, you can double-click on ret-run.cmd instead (it
just executes ret run, without requiring to open a
terminal).
The very first start should open a popup to request permission:
A "key" logo appears in the status bar whenever ret is active:
Alternatively, you can enable reverse tethering for all connected devices (present and future) by calling:
./ret autorun
The relay server then runs only while a client runs: it starts with the first client and stops when the last one stops, for example when its device is unplugged or the client is stopped from the device.
You can execute the actions separately (it may be useful if you want to reverse tether several devices simultaneously).
Start the relay server and keep it open:
./ret relay
Install the apk on your Android device:
./ret install [serial]
In another terminal, for each client, execute:
./ret start [serial]
To stop a client:
./ret stop [serial]
To reset the tunnel (useful to get the connection back when a device is unplugged and plugged back while ret is active):
./ret tunnel [serial]
The serial parameter is required only if adb devices outputs more than one
device.
For advanced options, run ./ret --help, or ./ret help <command> for the
details of one command (for example ./ret help start).
ret-ui is a window that does the same as the commands above. Its main page
lists the connected devices and shows the logs. Each device has a button to
start or stop its client, and a menu (the … button) to reset its tunnel or
reinstall the client. Headsets are shown with a headset icon, phones with a
phone icon.
The relay server runs by itself: it starts as soon as a client is started or found running, and stops once no client runs anymore. The header shows its state.
The gear button opens the settings, grouped by category:
- Connection: the port of the relay server, the DNS servers and the routes
- Devices: auto-start, which starts the client on every device as soon as it is connected (on by default)
- Appearance: the theme, light, dark or the same as the system
It is in the release archives next to ret. Start it with ./ret-ui (on
Windows, double-click on ret-ui.exe), with ret.apk in the same directory,
like for ret.
It reads the same environment variables as ret.
The window remembers its settings in config.toml, in a ret directory of the
user configuration directory:
- Linux:
~/.config/ret/config.toml(or$XDG_CONFIG_HOME/ret/config.toml) - Windows:
%APPDATA%\ret\config.toml
The window creates it with the default settings when it starts, and saves it as soon as a setting changes. You can also edit it by hand, every key is optional:
version = 1
port = 31416
dns_servers = ["1.1.1.1", "9.9.9.9"]
routes = ["10.0.0.0/8"]
autostart = true
theme = "system" # or "light", "dark"version is the layout of the file, which ret writes and upgrades itself. If
the file cannot be read, or was written by a newer version of ret, the window
starts with the default settings, logs the error and leaves the file untouched.
The window also saves its logs, one file per day, keeping the last 7, in a
ret/logs directory of the user data directory:
- Linux:
~/.local/share/ret/logs(or$XDG_DATA_HOME/ret/logs) - Windows:
%APPDATA%\ret\logs - macOS:
~/Library/Application Support/ret/logs
The ret program exposes a simple command-line interface that executes
lower-level commands. You can call them manually instead.
To start the relay server:
./ret relay
To install the apk:
adb install -r ret.apk
To start a client:
adb reverse localabstract:ret tcp:31416
adb shell am start -a dev.hoppou.ret.START \
-n dev.hoppou.ret/.RetActivity
To stop a client:
adb shell am start -a dev.hoppou.ret.STOP \
-n dev.hoppou.ret/.RetActivity
ADB defines a custom path to the adb executable, which ret uses to start
the adb server:
ADB=/path/to/my/adb ./ret runRET_APK defines a custom path to ret.apk. Without it, ret looks for
ret.apk in the current directory, then for the copy installed by the Arch
package at /usr/share/ret/ret.apk:
RET_APK=/usr/share/ret/ret.apk ./ret runRUST_LOG sets which logs are printed (info by default), for example to
print debug logs:
RUST_LOG=debug ./ret runIt also accepts per-component levels, such as
RUST_LOG=info,TcpConnection=debug.
It is short for reverse tethering. The upstream name, gnirehtet, is tethering reversed:
rev <<< tethering
(in Bash)
Read the developers page.
Copyright (C) 2017 Genymobile
Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License.
You may obtain a copy of the License at
http://www.apache.org/licenses/LICENSE-2.0
Unless required by applicable law or agreed to in writing, software
distributed under the License is distributed on an "AS IS" BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
See the License for the specific language governing permissions and
limitations under the License.