docker-compose.yaml

version: "3"

networks:
  # A non-default network is needed to control the IP address ranges (used in
  # some configs), and to avoid affecting other containers in the same Docker.
  vpn-network:
    driver: bridge
    ipam:
      driver: default
      config:
        - subnet: "172.30.172.0/24"
    enable_ipv6: false

services:

  # A sample application that runs securely only through the VPN, not directly.
  # It will not actually start until the firewall rules are applied (either
  # for the first time on creation, or pre-existing block-rules on restarts).
  # There can any amount of apps configured in the same setup: 0, 1, 2, so on.
  # If stopped, nothing will happen - the VPN remains available for other apps.
  transmission:
    build: .
    entrypoint: [/app/wait-for-safety.sh]
    command: [/app/transmission.sh]
    environment:
      LOCAL_IPS: 172.30.172.*
      PEER_PORT: 46112  # as (and if) configured in the VPN provider
    volumes:
      - ./:/app
      - ./transmission-state:/var/lib/transmission
      - ./transmission-files:/mnt/files
      - ~/Downloads:/mnt/downloads
      - ~/Movies:/mnt/movies
    cap_add: [NET_ADMIN]  # needed for the `wait-for-safety.sh` script
    restart: unless-stopped
    stop_signal: SIGTERM
    network_mode: service:network  # CRITICALLY IMPORTANT!

  # A shared container that is used as a network. It does nothing but sleeps.
  # Native Docker's networks cannot share the iptables rules cross containers.
  # The ports of all containers are shared here, as the network-bound containers
  # cannot share their own ports (including the VPN-secured application).
  network:
    build: .
    command: sleep infinity
    cap_add: [NET_ADMIN]  # needed only for debugging and README's simulations
    stop_signal: SIGKILL
    restart: always
    dns: [8.8.4.4]
    ports:
      - "127.0.0.1:9091:9091"  # application's ports
    networks:
      - vpn-network

  # Evaluates the status of the setup, and prints a colorful message about that.
  # It also generates an HTML file that is later served by the web-view server.
  # If stopped, the status is not checked and not updated, the old one is shown.
  status:
    build: .
    command:
      - bash
      - -c
      - |
        while true; do
          /report-status.sh
          cat /status/index.ansi
          sleep 5
        done
    environment:
      NS: 8.8.4.4
      TZ: Europe/Berlin
      STATUS_DIR: /status
    env_file:
      - ipstack.env
    volumes:
      - ./report-status.sh:/report-status.sh:ro
      - html:/status:rw
    restart: unless-stopped
    stop_signal: SIGKILL
    network_mode: service:network  # CRITICALLY IMPORTANT!

  # Connects and reconnects to the remote VPN server, creates the `tun` device,
  # configures the default traffic routing through VPN (only when connected).
  # If stopped, the `tun` device disappears for all other containers,
  # and the traffic is routed through the default `eth` device (if not blocked).
  openvpn:
    build: .
    command: ["openvpn", "--config", "client.conf"]
    volumes:
      - ./openvpn:/etc/openvpn:ro
    working_dir: /etc/openvpn/airvpn
    devices: [/dev/net/tun]
    cap_add: [NET_ADMIN]
    restart: unless-stopped
    stop_signal: SIGTERM
    network_mode: service:network  # CRITICALLY IMPORTANT!

  # Applies the firewall rules to block the traffic from going around VPN.
  # If stopped, the iptables rules remain applied, but are not re-applied,
  # which allows their modification manually (incl. unblocking the traffic).
  firewall:
    build: .
    command:
      - bash
      - -c
      - |
        /apply-firewall.sh initial
        while true; do
          /apply-firewall.sh
          sleep 1s
        done
    environment:
      IPTABLES_FILE_V4: /iptables/iptables-v4.txt
      IPTABLES_FILE_V6: /iptables/iptables-v6.txt
    volumes:
      - ./apply-firewall.sh:/apply-firewall.sh:ro
      - iptables:/iptables:ro
    cap_add: [NET_ADMIN]
    restart: unless-stopped
    stop_signal: SIGKILL
    network_mode: service:network  # CRITICALLY IMPORTANT!

  # Generates the firewall rules to be atmomically applied in another container.
  # It also resolves the IP addresses of the VPN provider into an allow-list,
  # so that the firewall would not block it on the default `eth` interface.
  # See the notes in `generate-firewall.sh` on why this needs to be isolated.
  # If stopped, the dump files are not generated, so they will not be applied.
  rulemaker:
    build: .
    command:
      - bash
      - -c
      - |
        /generate-firewall.sh initial  # silent insta-block!
        while true; do
          /update-airvpn-ips.sh
          /generate-firewall.sh
          sleep 600
        done
    environment:
      IPTABLES_FILE_V4: /iptables/iptables-v4.txt
      IPTABLES_FILE_V6: /iptables/iptables-v6.txt
      ALLOWED_IPS_FILE: /cache/all.txt
      ALLOWED_IPS_DIR: /cache
      LOCAL_IPS: 172.30.172.0/24
      STATUS_IP: 139.130.4.5
      NS: 8.8.4.4
    volumes:
      - ./cache:/cache
      - ./update-airvpn-ips.sh:/update-airvpn-ips.sh:ro
      - ./generate-firewall.sh:/generate-firewall.sh:ro
      - iptables:/iptables:rw
    dns: [8.8.4.4, 8.8.8.8]
    cap_add: [NET_ADMIN]
    restart: unless-stopped
    stop_signal: SIGKILL
    network_mode: bridge  # NB! See the comment above, and generate-firewall.sh.

  # A supplimentary web server to publish the HTML status page.
  # If stopped, the status will not be served via HTTP, but will be shown
  # in the output anyway; the HTML page will also be generated anyway.
  # Note: it is not a part of the firewalled network, as there is no need
  # for utilities to be firewalled. And so, it can have its own ports exposed.
  # TODO: Is there a proper "Docker way" to run nginx in the "status" container?
  webview:
    image: nginx
    volumes:
    - ./nginx-no-access-log.conf:/etc/nginx/conf.d/nginx-no-access-log.conf:ro
    - html:/usr/share/nginx/html:ro
    restart: unless-stopped
    stop_signal: SIGTERM
    ports:
      - "127.0.0.1:9090:80"

volumes:
  iptables:
  html: