/tor-alpine

:whale: A Small Tor Relay Server with obfs4proxy on Alpine Linux on Docker

Primary LanguageDockerfileMIT LicenseMIT

Tor Relay Server on Docker (Alpine)

example workflow

A complete, efficient and secure Tor relay server Docker image

This docker image, when rebuilt, will update automatically to the latest Alpine base image and install the latest current stable version of Tor server. It will run Tor as an unprivileged regular user, as recommended by torproject.org.

It includes the latest Tor Alpine package from torproject.org which is installed and configured according the Tor project recommendations. Additionally it can be run as a hidden bridge using and obfs4proxy as well as meek.

The Tor network relies on volunteers to donate bandwidth. The more people who run relays, the faster the Tor network will be. If you have at least 2 megabits/s for both upload and download, please help out Tor by configuring your server to be a Tor relay too.

Tor

Tor is free software and an open network that helps you defend against traffic analysis, a form of network surveillance that threatens personal freedom and privacy, confidential business activities and relationships, and state security.

  • Tor prevents people from learning your location or browsing habits.
  • Tor is for web browsers, instant messaging clients, and more.
  • Tor is free and open source for Windows, Mac, Linux/Unix, and Android

Quickstart - Tor relay server in minutes

Create a directory for your Tor server data. Then set your own Nickname (only letters and numbers) and an optional contact Email (which will be published on the Tor network) using environment variables:

mkdir -vp tor-data && \
docker run -d --init --name=tor-server_relay_1 --net=host \
-e TOR_NICKNAME=Tor4 \
-e CONTACT_EMAIL=tor4@example.org \
-v $PWD/tor-data:/var/lib/tor \
--restart=always raminmt/tor-alpine

This command will run a Tor relay server with a safe default configuration (not as an exit node). The server will autostart after restarting the host system. If you do not change the default Nickname 'Tor4', the startup script will add a randomized, pronouncable suffix to create a unique name. All Tor data will be preserved in the mounted Data Directory, even if you upgrade or remove the container.

Check with docker logs -f tor-server_relay_1 If you see the message: [notice] Self-testing indicates your ORPort is reachable from the outside. Excellent. Publishing server descriptor. at the bottom after a while, your server started successfully. Then wait a bit longer and search for your server here: Relay Search

Customize Tor configuration

You may want to configure additional options to control your monthly data usage, or to run Tor as a hidden obfuscated bridge. Look at the Tor manual with all Configuration File Options. Also refer to a recent fully commented torrc.sample:

docker cp tor-server_relay_1:/usr/local/etc/tor/torrc.sample ./

For customisation copy torrc to the host and configure the desired settings.

##=================== /etc/torrc =====================##
# Run Tor as a regular user (do not change this)
User tord
DataDirectory /var/lib/tor

# Port to advertise for incoming Tor connections.
ORPort 9001                 # common ports are 9001, 443
#ORPort [IPv6-address]:9001

# Mirror directory information for others
DirPort 9030

# Run as a relay only (change policy to enable exit node)
ExitPolicy reject *:*       # no exits allowed
ExitPolicy reject6 *:*

# Run Tor only as a server (no local applications)
SocksPort 0
ControlSocket 0

#Nickname Tor4example         # only use letters and numbers
#ContactInfo tor4@example.org

Run Tor with a mounted torrc configuration

Mount your customized torrc from the current directory of the host into the container with this command:

nano torrc

mkdir -vp tor-data && \
docker run -d --init --name=tor-server_relay_1 --net=host \
-e TOR_NICKNAME=Tor4 \
-e CONTACT_EMAIL=tor4@example.org \
-v $PWD/tor-data:/var/lib/tor \
-v $PWD/torrc:/etc/tor/torrc \
--restart=always raminmt/tor-alpine

Move or upgrade the Tor relay

When upgrading your Tor relay, or moving it on a different computer, the important part is to keep the same identity keys. Keeping backups of the identity keys so you can restore a relay in the future is the recommended way to ensure the reputation of the relay won't be wasted.

mkdir -vp tor-data/keys/ && \
docker cp tor-server_relay_1:/var/lib/tor/keys/secret_id_key ./tor-data/keys/ && \
docker cp tor-server_relay_1:/var/lib/tor/keys/ed25519_master_id_secret_key ./tor-data/keys/

You can also reuse these identity keys from a previous Tor relay server installation, to continue with the same Fingerprint and ID, by inserting the following lines, in the previous command:

-v $PWD/tor-data/keys/secret_id_key:/var/lib/tor/keys/secret_id_key \
-v $PWD/tor-data/keys/ed25519_master_id_secret_key:/var/lib/tor/ed25519_master_id_secret_key \

Run Tor using docker-compose (recommended)

Adapt the example docker-compose.yml with your settings or clone it from Github.

version: '2.2'
services:
  relay:
    image: raminmt/tor-alpine
    init: true
    restart: always
    network_mode: host
    environment:
      TOR_NICKNAME: Tor4
      CONTACT_EMAIL: tor4@example.org
    volumes:
      - ./tor-data/:/var/lib/tor/
      - ./torrc:/etc/tor/torrc
Configure and run the Tor relay server
  • Configure the docker-compose.yml and optionally the torrc file, with your individual settings. Possibly install git first.
cd /opt && git clone https://github.com/raminmt/tor-alpine.git && cd tor-alpine
nano docker-compose.yml
  • Start a new instance of the Tor relay server and display the logs.
docker-compose up -d
docker-compose logs -f
  • As examples for running commands in the container, show the current fingerprint or enter a bash shell.
docker-compose exec -T relay cat /var/lib/tor/fingerprint
docker-compose exec relay bash
  • Enter a container which is restarting with an error to inspect it
docker run -it --entrypoint=/bin/sh raminmt/tor-alpine --login

Run Tor relay with IPv6

If your host supports IPv6, please enable it! The host system or VPS (for example Vultr) needs to have IPv6 activated. From your host server try to ping any IPv6 host: ping6 -c 5 ipv6.google.com Then find out your external IPv6 address with this command:

dig +short -6 myip.opendns.com aaaa @resolver1.ipv6-sandbox.opendns.com

If that works fine, activate IPv6 for Docker by adding the following to the file daemon.json on the docker host and restarting Docker.

  • use the IPv6 subnet/64 address from your provider for fixed-cidr-v6
nano /etc/docker/daemon.json

    {
    "ipv6": true,
    "fixed-cidr-v6": "21ch:ange:this:addr::/64"
    }

systemctl restart docker && systemctl status docker

My sample Tor relay server configurations use network_mode: host which makes it easier to use IPv6. - Next make your Tor relay reachable via IPv6 by adding the applicable IPv6 address at the ORPort line in your torrc configuration:

ORPort [IPv6-address]:9001

Or use the included helper script to add the main IPv6 address of your host to your torrc, for example:

bash scripts/set-ipv6-in-torrc.sh torrc

  • Restart the container and test, that the Tor relay can reach the outside world:
docker-compose restart
docker-compose logs
docker-compose exec -T relay ping6 -c 5 ipv6.google.com

You should see something like this in the log: [notice] Opening OR listener on [2200:2400:4400:4a61:5400:4ff:f444:e448]:9001

Install Docker and Docker Compose

Links how to install

After the installation process is finished, you may need to enable the service and make sure it is started (e.g. CentOS).

systemctl enable docker
systemctl start docker

Please use the latest Docker engine available and do not use the engine that ships with your distro's repository.

Guides

License:

  • MIT