fix(vpnunlimited): lower TLS security level to 0 (#1476)

- remove issue category labels
- Add temporary status labels
- Add complexity labels

.devcontainer/Dockerfile

@@ -1,2 +1,2 @@
 FROM qmcgaw/godevcontainer
-RUN apk add wireguard-tools htop
+RUN apk add wireguard-tools htop openssl

.devcontainer/docker-compose.yml

@@ -12,10 +12,10 @@ services:
       # Docker configuration
       - ~/.docker:/root/.docker
       # SSH directory for Linux, OSX and WSL
-      - ~/.ssh:/root/.ssh
-      # For Windows without WSL, a copy will be made
-      # from /tmp/.ssh to ~/.ssh to fix permissions
-      #- ~/.ssh:/tmp/.ssh:ro
+      # On Linux and OSX, a symlink /mnt/ssh <-> ~/.ssh is
+      # created in the container. On Windows, files are copied
+      # from /mnt/ssh to ~/.ssh to fix permissions.
+      - ~/.ssh:/mnt/ssh
       # Shell history persistence
       - ~/.zsh_history:/root/.zsh_history
       # Git config

.github/ISSUE_TEMPLATE/bug.yml

@@ -40,6 +40,7 @@ body:
     attributes:
       label: VPN service provider
       options:
+        - AirVPN
         - Custom
         - Cyberghost
         - ExpressVPN

.github/labels.yml

@@ -1,18 +1,13 @@
-- name: "Bug :bug:"
-  color: "b60205"
-  description: ""
-- name: "Feature request :bulb:"
-  color: "0e8a16"
-  description: ""
-- name: "Help wanted :pray:"
-  color: "4caf50"
-  description: ""
-- name: "Documentation :memo:"
-  color: "c5def5"
-  description: ""
-- name: "Needs more info :thinking:"
-  color: "795548"
+# Temporary status
+- name: "🗯️ Waiting for feedback"
+  color: "aadefa"
   description: ""
+- name: "🔴 Blocked"
+  color: "ff3f14"
+  description: "Blocked by another issue or pull request"
+- name: "🔒 After next release"
+  color: "e8f274"
+  description: "Will be done after the next release"
 
 # Priority
 - name: "🚨 Urgent"
@@ -22,7 +17,18 @@
   color: "4285f4"
   description: ""
 
+# Complexity
+- name: "☣️ Hard to do"
+  color: "7d0008"
+  description: ""
+- name: "🟩 Easy to do"
+  color: "34cf43"
+  description: ""
+
 # VPN providers
+- name: ":cloud: AirVPN"
+  color: "cfe8d4"
+  description: ""
 - name: ":cloud: Cyberghost"
   color: "cfe8d4"
   description: ""

.github/workflows/ci.yml

@@ -45,6 +45,8 @@ jobs:
         with:
           locale: "US"
           level: error
+          exclude: |
+            ./internal/storage/servers.json
 
       - name: Linting
         run: docker build --target lint .
@@ -91,6 +93,7 @@ jobs:
     permissions:
       actions: read
       contents: read
+      packages: write
     runs-on: ubuntu-latest
     steps:
       - uses: actions/checkout@v3
@@ -104,6 +107,7 @@ jobs:
           flavor: |
             latest=${{ github.ref == format('refs/heads/{0}', github.event.repository.default_branch) }}
           images: |
+            ghcr.io/qdm12/gluetun
             qmcgaw/gluetun
             qmcgaw/private-internet-access
           tags: |
@@ -121,12 +125,18 @@ jobs:
           username: qmcgaw
           password: ${{ secrets.DOCKERHUB_PASSWORD }}
 
+      - uses: docker/login-action@v2
+        with:
+          registry: ghcr.io
+          username: qdm12
+          password: ${{ github.token }}
+
       - name: Short commit
         id: shortcommit
         run: echo "::set-output name=value::$(git rev-parse --short HEAD)"
 
       - name: Build and push final image
-        uses: docker/build-push-action@v3.1.1
+        uses: docker/build-push-action@v4.0.0
         with:
           platforms: linux/amd64,linux/386,linux/arm64,linux/arm/v6,linux/arm/v7,linux/ppc64le
           labels: ${{ steps.meta.outputs.labels }}

.vscode/launch.json

@@ -5,11 +5,11 @@
             "name": "Update a VPN provider servers data",
             "type": "go",
             "request": "launch",
-            "mode": "debug",
+            "cwd": "${workspaceFolder}",
             "program": "cmd/gluetun/main.go",
             "args": [
                 "update",
-                "-enduser",
+                "${input:updateMode}",
                 "-providers",
                 "${input:provider}"
             ],
@@ -20,6 +20,16 @@
             "id": "provider",
             "type": "promptString",
             "description": "Please enter a provider (or comma separated list of providers)",
-        }
+        },
+        {
+            "id": "updateMode",
+            "type": "pickString",
+            "description": "Update mode to use",
+            "options": [
+                "-maintainer",
+                "-enduser"
+            ],
+            "default": "-maintainer"
+        },
     ]
 }

Dockerfile

@@ -1,8 +1,8 @@
-ARG ALPINE_VERSION=3.16
-ARG GO_ALPINE_VERSION=3.16
-ARG GO_VERSION=1.17
+ARG ALPINE_VERSION=3.17
+ARG GO_ALPINE_VERSION=3.17
+ARG GO_VERSION=1.20
 ARG XCPUTRANSLATE_VERSION=v0.6.0
-ARG GOLANGCI_LINT_VERSION=v1.49.0
+ARG GOLANGCI_LINT_VERSION=v1.51.2
 ARG MOCKGEN_VERSION=v1.6.0
 ARG BUILDPLATFORM=linux/amd64
 
@@ -91,13 +91,13 @@ ENV VPN_SERVICE_PROVIDER=pia \
     OPENVPN_CIPHERS= \
     OPENVPN_AUTH= \
     OPENVPN_PROCESS_USER= \
-    OPENVPN_IPV6=off \
     OPENVPN_CUSTOM_CONFIG= \
     # Wireguard
     WIREGUARD_PRIVATE_KEY= \
     WIREGUARD_PRESHARED_KEY= \
     WIREGUARD_PUBLIC_KEY= \
     WIREGUARD_ADDRESSES= \
+    WIREGUARD_IMPLEMENTATION=auto \
     # VPN server filtering
     SERVER_REGIONS= \
     SERVER_COUNTRIES= \
@@ -197,8 +197,9 @@ ENTRYPOINT ["/gluetun-entrypoint"]
 EXPOSE 8000/tcp 8888/tcp 8388/tcp 8388/udp
 HEALTHCHECK --interval=5s --timeout=5s --start-period=10s --retries=1 CMD /gluetun-entrypoint healthcheck
 ARG TARGETPLATFORM
-RUN apk add --no-cache --update -l apk-tools && \
+RUN apk add --no-cache --update -l wget && \
     apk add --no-cache --update -X "https://dl-cdn.alpinelinux.org/alpine/v3.12/main" openvpn==2.4.12-r0 && \
+    apk add --no-cache --update -X "https://dl-cdn.alpinelinux.org/alpine/v3.16/main" openssl\~1.1 && \
     mv /usr/sbin/openvpn /usr/sbin/openvpn2.4 && \
     apk del openvpn && \
     apk add --no-cache --update openvpn ca-certificates iptables ip6tables unbound tzdata && \

README.md

@@ -1,125 +1,130 @@
-# Gluetun VPN client
-
-Lightweight swiss-knife-like VPN client to multiple VPN service providers
-
-![Title image](https://raw.githubusercontent.com/qdm12/gluetun/master/title.svg)
-
-[![Build status](https://github.com/qdm12/gluetun/actions/workflows/ci.yml/badge.svg)](https://github.com/qdm12/gluetun/actions/workflows/ci.yml)
-
-[![Docker pulls qmcgaw/gluetun](https://img.shields.io/docker/pulls/qmcgaw/gluetun.svg)](https://hub.docker.com/r/qmcgaw/gluetun)
-[![Docker pulls qmcgaw/private-internet-access](https://img.shields.io/docker/pulls/qmcgaw/private-internet-access.svg)](https://hub.docker.com/r/qmcgaw/gluetun)
-
-[![Docker stars qmcgaw/gluetun](https://img.shields.io/docker/stars/qmcgaw/gluetun.svg)](https://hub.docker.com/r/qmcgaw/gluetun)
-[![Docker stars qmcgaw/private-internet-access](https://img.shields.io/docker/stars/qmcgaw/private-internet-access.svg)](https://hub.docker.com/r/qmcgaw/gluetun)
-
-![Last release](https://img.shields.io/github/release/qdm12/gluetun?label=Last%20release)
-![Last Docker tag](https://img.shields.io/docker/v/qmcgaw/gluetun?sort=semver&label=Last%20Docker%20tag)
-[![Last release size](https://img.shields.io/docker/image-size/qmcgaw/gluetun?sort=semver&label=Last%20released%20image)](https://hub.docker.com/r/qmcgaw/gluetun/tags?page=1&ordering=last_updated)
-![GitHub last release date](https://img.shields.io/github/release-date/qdm12/gluetun?label=Last%20release%20date)
-![Commits since release](https://img.shields.io/github/commits-since/qdm12/gluetun/latest?sort=semver)
-
-[![Latest size](https://img.shields.io/docker/image-size/qmcgaw/gluetun/latest?label=Latest%20image)](https://hub.docker.com/r/qmcgaw/gluetun/tags)
-
-[![GitHub last commit](https://img.shields.io/github/last-commit/qdm12/gluetun.svg)](https://github.com/qdm12/gluetun/commits/master)
-[![GitHub commit activity](https://img.shields.io/github/commit-activity/y/qdm12/gluetun.svg)](https://github.com/qdm12/gluetun/graphs/contributors)
-[![GitHub closed PRs](https://img.shields.io/github/issues-pr-closed/qdm12/gluetun.svg)](https://github.com/qdm12/gluetun/pulls?q=is%3Apr+is%3Aclosed)
-[![GitHub issues](https://img.shields.io/github/issues/qdm12/gluetun.svg)](https://github.com/qdm12/gluetun/issues)
-[![GitHub closed issues](https://img.shields.io/github/issues-closed/qdm12/gluetun.svg)](https://github.com/qdm12/gluetun/issues?q=is%3Aissue+is%3Aclosed)
-
-[![Lines of code](https://img.shields.io/tokei/lines/github/qdm12/gluetun)](https://github.com/qdm12/gluetun)
-![Code size](https://img.shields.io/github/languages/code-size/qdm12/gluetun)
-![GitHub repo size](https://img.shields.io/github/repo-size/qdm12/gluetun)
-![Go version](https://img.shields.io/github/go-mod/go-version/qdm12/gluetun)
-
-![Visitors count](https://visitor-badge.laobi.icu/badge?page_id=gluetun.readme)
-
-## Quick links
-
-- [Setup](#Setup)
-- [Features](#Features)
-- Problem?
-  - [Check the Wiki](https://github.com/qdm12/gluetun/wiki)
-  - [Start a discussion](https://github.com/qdm12/gluetun/discussions)
-  - [Fix the Unraid template](https://github.com/qdm12/gluetun/discussions/550)
-- Suggestion?
-  - [Create an issue](https://github.com/qdm12/gluetun/issues)
-  - [Join the Slack channel](https://join.slack.com/t/qdm12/shared_invite/enQtOTE0NjcxNTM1ODc5LTYyZmVlOTM3MGI4ZWU0YmJkMjUxNmQ4ODQ2OTAwYzMxMTlhY2Q1MWQyOWUyNjc2ODliNjFjMDUxNWNmNzk5MDk)
-- Happy?
-  - Sponsor me on [github.com/sponsors/qdm12](https://github.com/sponsors/qdm12)
-  - Donate to [paypal.me/qmcgaw](https://www.paypal.me/qmcgaw)
-  - Drop me [an email](mailto:quentin.mcgaw@gmail.com)
-- **Want to add a VPN provider?** check [Development](https://github.com/qdm12/gluetun/wiki/Development) and [Add a provider](https://github.com/qdm12/gluetun/wiki/Add-a-provider)
-- Video:
-
-  [![Video Gif](https://i.imgur.com/CetWunc.gif)](https://youtu.be/0F6I03LQcI4)
-
-- [Substack Console interview](https://console.substack.com/p/console-72)
-
-## Features
-
-- Based on Alpine 3.16 for a small Docker image of 29MB
-- Supports: **Cyberghost**, **ExpressVPN**, **FastestVPN**, **HideMyAss**, **IPVanish**, **IVPN**, **Mullvad**, **NordVPN**, **Perfect Privacy**, **Privado**, **Private Internet Access**, **PrivateVPN**, **ProtonVPN**, **PureVPN**,  **SlickVPN**, **Surfshark**, **TorGuard**, **VPNSecure.me**, **VPNUnlimited**, **Vyprvpn**, **WeVPN**, **Windscribe** servers
-- Supports OpenVPN for all providers listed
-- Supports Wireguard both kernelspace and userspace
-  - For **Mullvad**, **Ivpn** and **Windscribe**
-  - For **Torguard**, **VPN Unlimited** and **WeVPN** using [the custom provider](https://github.com/qdm12/gluetun/wiki/Custom-provider)
-  - For custom Wireguard configurations using [the custom provider](https://github.com/qdm12/gluetun/wiki/Custom-provider)
-  - More in progress, see [#134](https://github.com/qdm12/gluetun/issues/134)
-- DNS over TLS baked in with service provider(s) of your choice
-- DNS fine blocking of malicious/ads/surveillance hostnames and IP addresses, with live update every 24 hours
-- Choose the vpn network protocol, `udp` or `tcp`
-- Built in firewall kill switch to allow traffic only with needed the VPN servers and LAN devices
-- Built in Shadowsocks proxy (protocol based on SOCKS5 with an encryption layer, tunnels TCP+UDP)
-- Built in HTTP proxy (tunnels HTTP and HTTPS through TCP)
-- [Connect other containers to it](https://github.com/qdm12/gluetun/wiki/Connect-a-container-to-gluetun)
-- [Connect LAN devices to it](https://github.com/qdm12/gluetun/wiki/Connect-a-LAN-device-to-gluetun)
-- Compatible with amd64, i686 (32 bit), **ARM** 64 bit, ARM 32 bit v6 and v7, and even ppc64le 🎆
-- [Custom VPN server side port forwarding for Private Internet Access](https://github.com/qdm12/gluetun/wiki/Private-internet-access#vpn-server-port-forwarding)
-- Possibility of split horizon DNS by selecting multiple DNS over TLS providers
-- Unbound subprogram drops root privileges once launched
-- Can work as a Kubernetes sidecar container, thanks @rorph
-
-## Setup
-
-🎉 There are now instructions specific to each VPN provider with examples to help you get started as quickly as possible!
-
-Go to the [Wiki](https://github.com/qdm12/gluetun/wiki)!
-
-[🐛 Found a bug in the Wiki?!](https://github.com/qdm12/gluetun/issues/new?assignees=&labels=%F0%9F%93%84+Wiki+issue&template=wiki+issue.yml&title=Wiki+issue%3A+)
-
-Here's a docker-compose.yml for the laziest:
-
-```yml
-version: "3"
-services:
-  gluetun:
-    image: qmcgaw/gluetun
-    # container_name: gluetun
-    # line above must be uncommented to allow external containers to connect. See https://github.com/qdm12/gluetun/wiki/Connect-a-container-to-gluetun#external-container-to-gluetun
-    cap_add:
-      - NET_ADMIN
-    devices:
-      - /dev/net/tun:/dev/net/tun
-    ports:
-      - 8888:8888/tcp # HTTP proxy
-      - 8388:8388/tcp # Shadowsocks
-      - 8388:8388/udp # Shadowsocks
-    volumes:
-      - /yourpath:/gluetun
-    environment:
-      # See https://github.com/qdm12/gluetun/wiki
-      - VPN_SERVICE_PROVIDER=ivpn
-      - VPN_TYPE=openvpn
-      # OpenVPN:
-      - OPENVPN_USER=
-      - OPENVPN_PASSWORD=
-      # Wireguard:
-      # - WIREGUARD_PRIVATE_KEY=wOEI9rqqbDwnN8/Bpp22sVz48T71vJ4fYmFWujulwUU=
-      # - WIREGUARD_ADDRESSES=10.64.222.21/32
-      # Timezone for accurate log times
-      - TZ=
-```
-
-## License
-
-[![MIT](https://img.shields.io/github/license/qdm12/gluetun)](https://github.com/qdm12/gluetun/master/LICENSE)
+# Gluetun VPN client
+
+Lightweight swiss-knife-like VPN client to multiple VPN service providers
+
+![Title image](https://raw.githubusercontent.com/qdm12/gluetun/master/title.svg)
+
+[![Build status](https://github.com/qdm12/gluetun/actions/workflows/ci.yml/badge.svg)](https://github.com/qdm12/gluetun/actions/workflows/ci.yml)
+
+[![Docker pulls qmcgaw/gluetun](https://img.shields.io/docker/pulls/qmcgaw/gluetun.svg)](https://hub.docker.com/r/qmcgaw/gluetun)
+[![Docker pulls qmcgaw/private-internet-access](https://img.shields.io/docker/pulls/qmcgaw/private-internet-access.svg)](https://hub.docker.com/r/qmcgaw/gluetun)
+
+[![Docker stars qmcgaw/gluetun](https://img.shields.io/docker/stars/qmcgaw/gluetun.svg)](https://hub.docker.com/r/qmcgaw/gluetun)
+[![Docker stars qmcgaw/private-internet-access](https://img.shields.io/docker/stars/qmcgaw/private-internet-access.svg)](https://hub.docker.com/r/qmcgaw/gluetun)
+
+![Last release](https://img.shields.io/github/release/qdm12/gluetun?label=Last%20release)
+![Last Docker tag](https://img.shields.io/docker/v/qmcgaw/gluetun?sort=semver&label=Last%20Docker%20tag)
+[![Last release size](https://img.shields.io/docker/image-size/qmcgaw/gluetun?sort=semver&label=Last%20released%20image)](https://hub.docker.com/r/qmcgaw/gluetun/tags?page=1&ordering=last_updated)
+![GitHub last release date](https://img.shields.io/github/release-date/qdm12/gluetun?label=Last%20release%20date)
+![Commits since release](https://img.shields.io/github/commits-since/qdm12/gluetun/latest?sort=semver)
+
+[![Latest size](https://img.shields.io/docker/image-size/qmcgaw/gluetun/latest?label=Latest%20image)](https://hub.docker.com/r/qmcgaw/gluetun/tags)
+
+[![GitHub last commit](https://img.shields.io/github/last-commit/qdm12/gluetun.svg)](https://github.com/qdm12/gluetun/commits/master)
+[![GitHub commit activity](https://img.shields.io/github/commit-activity/y/qdm12/gluetun.svg)](https://github.com/qdm12/gluetun/graphs/contributors)
+[![GitHub closed PRs](https://img.shields.io/github/issues-pr-closed/qdm12/gluetun.svg)](https://github.com/qdm12/gluetun/pulls?q=is%3Apr+is%3Aclosed)
+[![GitHub issues](https://img.shields.io/github/issues/qdm12/gluetun.svg)](https://github.com/qdm12/gluetun/issues)
+[![GitHub closed issues](https://img.shields.io/github/issues-closed/qdm12/gluetun.svg)](https://github.com/qdm12/gluetun/issues?q=is%3Aissue+is%3Aclosed)
+
+[![Lines of code](https://img.shields.io/tokei/lines/github/qdm12/gluetun)](https://github.com/qdm12/gluetun)
+![Code size](https://img.shields.io/github/languages/code-size/qdm12/gluetun)
+![GitHub repo size](https://img.shields.io/github/repo-size/qdm12/gluetun)
+![Go version](https://img.shields.io/github/go-mod/go-version/qdm12/gluetun)
+
+![Visitors count](https://visitor-badge.laobi.icu/badge?page_id=gluetun.readme)
+
+## Quick links
+
+- [Setup](#Setup)
+- [Features](#Features)
+- Problem?
+  - [Check the Wiki](https://github.com/qdm12/gluetun/wiki)
+  - [Start a discussion](https://github.com/qdm12/gluetun/discussions)
+  - [Fix the Unraid template](https://github.com/qdm12/gluetun/discussions/550)
+- Suggestion?
+  - [Create an issue](https://github.com/qdm12/gluetun/issues)
+  - [Join the Slack channel](https://join.slack.com/t/qdm12/shared_invite/enQtOTE0NjcxNTM1ODc5LTYyZmVlOTM3MGI4ZWU0YmJkMjUxNmQ4ODQ2OTAwYzMxMTlhY2Q1MWQyOWUyNjc2ODliNjFjMDUxNWNmNzk5MDk)
+- Happy?
+  - Sponsor me on [github.com/sponsors/qdm12](https://github.com/sponsors/qdm12)
+  - Donate to [paypal.me/qmcgaw](https://www.paypal.me/qmcgaw)
+  - Drop me [an email](mailto:quentin.mcgaw@gmail.com)
+- **Want to add a VPN provider?** check [Development](https://github.com/qdm12/gluetun/wiki/Development) and [Add a provider](https://github.com/qdm12/gluetun/wiki/Add-a-provider)
+- Video:
+
+  [![Video Gif](https://i.imgur.com/CetWunc.gif)](https://youtu.be/0F6I03LQcI4)
+
+- [Substack Console interview](https://console.substack.com/p/console-72)
+
+## Features
+
+- Based on Alpine 3.17 for a small Docker image of 42MB
+- Supports: **AirVPN**, **Cyberghost**, **ExpressVPN**, **FastestVPN**, **HideMyAss**, **IPVanish**, **IVPN**, **Mullvad**, **NordVPN**, **Perfect Privacy**, **Privado**, **Private Internet Access**, **PrivateVPN**, **ProtonVPN**, **PureVPN**,  **SlickVPN**, **Surfshark**, **TorGuard**, **VPNSecure.me**, **VPNUnlimited**, **Vyprvpn**, **WeVPN**, **Windscribe** servers
+- Supports OpenVPN for all providers listed
+- Supports Wireguard both kernelspace and userspace
+  - For **Mullvad**, **Ivpn**, **Surfshark** and **Windscribe**
+  - For **ProtonVPN**, **PureVPN**, **Torguard**, **VPN Unlimited** and **WeVPN** using [the custom provider](https://github.com/qdm12/gluetun/wiki/Custom-provider)
+  - For custom Wireguard configurations using [the custom provider](https://github.com/qdm12/gluetun/wiki/Custom-provider)
+  - More in progress, see [#134](https://github.com/qdm12/gluetun/issues/134)
+- DNS over TLS baked in with service provider(s) of your choice
+- DNS fine blocking of malicious/ads/surveillance hostnames and IP addresses, with live update every 24 hours
+- Choose the vpn network protocol, `udp` or `tcp`
+- Built in firewall kill switch to allow traffic only with needed the VPN servers and LAN devices
+- Built in Shadowsocks proxy (protocol based on SOCKS5 with an encryption layer, tunnels TCP+UDP)
+- Built in HTTP proxy (tunnels HTTP and HTTPS through TCP)
+- [Connect other containers to it](https://github.com/qdm12/gluetun/wiki/Connect-a-container-to-gluetun)
+- [Connect LAN devices to it](https://github.com/qdm12/gluetun/wiki/Connect-a-LAN-device-to-gluetun)
+- Compatible with amd64, i686 (32 bit), **ARM** 64 bit, ARM 32 bit v6 and v7, and even ppc64le 🎆
+- [Custom VPN server side port forwarding for Private Internet Access](https://github.com/qdm12/gluetun/wiki/Private-internet-access#vpn-server-port-forwarding)
+- Possibility of split horizon DNS by selecting multiple DNS over TLS providers
+- Unbound subprogram drops root privileges once launched
+- Can work as a Kubernetes sidecar container, thanks @rorph
+
+## Setup
+
+🎉 There are now instructions specific to each VPN provider with examples to help you get started as quickly as possible!
+
+Go to the [Wiki](https://github.com/qdm12/gluetun/wiki)!
+
+[🐛 Found a bug in the Wiki?!](https://github.com/qdm12/gluetun/issues/new?assignees=&labels=%F0%9F%93%84+Wiki+issue&template=wiki+issue.yml&title=Wiki+issue%3A+)
+
+Here's a docker-compose.yml for the laziest:
+
+```yml
+version: "3"
+services:
+  gluetun:
+    image: qmcgaw/gluetun
+    # container_name: gluetun
+    # line above must be uncommented to allow external containers to connect. See https://github.com/qdm12/gluetun/wiki/Connect-a-container-to-gluetun#external-container-to-gluetun
+    cap_add:
+      - NET_ADMIN
+    devices:
+      - /dev/net/tun:/dev/net/tun
+    ports:
+      - 8888:8888/tcp # HTTP proxy
+      - 8388:8388/tcp # Shadowsocks
+      - 8388:8388/udp # Shadowsocks
+    volumes:
+      - /yourpath:/gluetun
+    environment:
+      # See https://github.com/qdm12/gluetun/wiki
+      - VPN_SERVICE_PROVIDER=ivpn
+      - VPN_TYPE=openvpn
+      # OpenVPN:
+      - OPENVPN_USER=
+      - OPENVPN_PASSWORD=
+      # Wireguard:
+      # - WIREGUARD_PRIVATE_KEY=wOEI9rqqbDwnN8/Bpp22sVz48T71vJ4fYmFWujulwUU=
+      # - WIREGUARD_ADDRESSES=10.64.222.21/32
+      # Timezone for accurate log times
+      - TZ=
+      # Server list updater. See https://github.com/qdm12/gluetun/wiki/Updating-Servers#periodic-update
+      - UPDATER_PERIOD=
+      - UPDATER_VPN_SERVICE_PROVIDERS=
+```
+
+🆕 Image also available as `ghcr.io/qdm12/gluetun`
+
+## License
+
+[![MIT](https://img.shields.io/github/license/qdm12/gluetun)](https://github.com/qdm12/gluetun/master/LICENSE)

cmd/gluetun/main.go

@@ -16,10 +16,10 @@ import (
 	"github.com/qdm12/dns/pkg/unbound"
 	"github.com/qdm12/gluetun/internal/alpine"
 	"github.com/qdm12/gluetun/internal/cli"
-	"github.com/qdm12/gluetun/internal/configuration/sources"
+	"github.com/qdm12/gluetun/internal/configuration/settings"
 	"github.com/qdm12/gluetun/internal/configuration/sources/env"
 	"github.com/qdm12/gluetun/internal/configuration/sources/files"
-	"github.com/qdm12/gluetun/internal/configuration/sources/mux"
+	mux "github.com/qdm12/gluetun/internal/configuration/sources/merge"
 	"github.com/qdm12/gluetun/internal/configuration/sources/secrets"
 	"github.com/qdm12/gluetun/internal/constants"
 	"github.com/qdm12/gluetun/internal/dns"
@@ -77,7 +77,8 @@ func main() {
 
 	args := os.Args
 	tun := tun.New()
-	netLinker := netlink.New()
+	netLinkDebugLogger := logger.New(log.SetComponent("netlink"))
+	netLinker := netlink.New(netLinkDebugLogger)
 	cli := cli.New()
 	cmder := command.NewCmder()
 
@@ -91,12 +92,13 @@ func main() {
 		errorCh <- _main(ctx, buildInfo, args, logger, muxReader, tun, netLinker, cmder, cli)
 	}()
 
+	var err error
 	select {
 	case signal := <-signalCh:
 		fmt.Println("")
 		logger.Warn("Caught OS signal " + signal.String() + ", shutting down")
 		cancel()
-	case err := <-errorCh:
+	case err = <-errorCh:
 		close(errorCh)
 		if err == nil { // expected exit such as healthcheck
 			os.Exit(0)
@@ -108,18 +110,27 @@ func main() {
 	const shutdownGracePeriod = 5 * time.Second
 	timer := time.NewTimer(shutdownGracePeriod)
 	select {
-	case <-errorCh:
+	case shutdownErr := <-errorCh:
 		if !timer.Stop() {
 			<-timer.C
 		}
+		if shutdownErr != nil {
+			logger.Warnf("Shutdown not completed gracefully: %s", shutdownErr)
+			os.Exit(1)
+		}
+
 		logger.Info("Shutdown successful")
+		if err != nil {
+			os.Exit(1)
+		}
+		os.Exit(0)
 	case <-timer.C:
 		logger.Warn("Shutdown timed out")
+		os.Exit(1)
 	case signal := <-signalCh:
 		logger.Warn("Caught OS signal " + signal.String() + ", forcing shut down")
+		os.Exit(1)
 	}
-
-	os.Exit(1)
 }
 
 var (
@@ -128,7 +139,7 @@ var (
 
 //nolint:gocognit,gocyclo,maintidx
 func _main(ctx context.Context, buildInfo models.BuildInformation,
-	args []string, logger log.LoggerInterface, source sources.Source,
+	args []string, logger log.LoggerInterface, source Source,
 	tun Tun, netLinker netLinker, cmder command.RunStarter,
 	cli clier) error {
 	if len(args) > 1 { // cli operation
@@ -138,7 +149,7 @@ func _main(ctx context.Context, buildInfo models.BuildInformation,
 		case "clientkey":
 			return cli.ClientKey(args[2:])
 		case "openvpnconfig":
-			return cli.OpenvpnConfig(logger, source)
+			return cli.OpenvpnConfig(logger, source, netLinker)
 		case "update":
 			return cli.Update(ctx, args[2:], logger)
 		case "format-servers":
@@ -179,6 +190,7 @@ func _main(ctx context.Context, buildInfo models.BuildInformation,
 	// - firewall Debug and Enabled are booleans parsed from source
 
 	logger.Patch(log.SetLevel(*allSettings.Log.Level))
+	netLinker.PatchLoggerLevel(*allSettings.Log.Level)
 
 	routingLogger := logger.New(log.SetComponent("routing"))
 	if *allSettings.Firewall.Debug { // To remove in v4
@@ -220,7 +232,12 @@ func _main(ctx context.Context, buildInfo models.BuildInformation,
 		return err
 	}
 
-	err = allSettings.Validate(storage)
+	ipv6Supported, err := netLinker.IsIPv6Supported()
+	if err != nil {
+		return fmt.Errorf("checking for IPv6 support: %w", err)
+	}
+
+	err = allSettings.Validate(storage, ipv6Supported)
 	if err != nil {
 		return err
 	}
@@ -228,7 +245,7 @@ func _main(ctx context.Context, buildInfo models.BuildInformation,
 	allSettings.Pprof.HTTPServer.Logger = logger.New(log.SetComponent("pprof"))
 	pprofServer, err := pprof.New(allSettings.Pprof)
 	if err != nil {
-		return fmt.Errorf("cannot create Pprof server: %w", err)
+		return fmt.Errorf("creating Pprof server: %w", err)
 	}
 
 	puid, pgid := int(*allSettings.System.PUID), int(*allSettings.System.PGID)
@@ -260,6 +277,10 @@ func _main(ctx context.Context, buildInfo models.BuildInformation,
 
 	logger.Info(allSettings.String())
 
+	for _, warning := range allSettings.Warnings() {
+		logger.Warn(warning)
+	}
+
 	if err := os.MkdirAll("/tmp/gluetun", 0644); err != nil {
 		return err
 	}
@@ -270,7 +291,7 @@ func _main(ctx context.Context, buildInfo models.BuildInformation,
 	const defaultUsername = "nonrootuser"
 	nonRootUsername, err := alpineConf.CreateUser(defaultUsername, puid)
 	if err != nil {
-		return fmt.Errorf("cannot create user: %w", err)
+		return fmt.Errorf("creating user: %w", err)
 	}
 	if nonRootUsername != defaultUsername {
 		logger.Info("using existing username " + nonRootUsername + " corresponding to user id " + fmt.Sprint(puid))
@@ -288,7 +309,7 @@ func _main(ctx context.Context, buildInfo models.BuildInformation,
 		if strings.Contains(err.Error(), "operation not permitted") {
 			logger.Warn("💡 Tip: Are you passing NET_ADMIN capability to gluetun?")
 		}
-		return fmt.Errorf("cannot setup routing: %w", err)
+		return fmt.Errorf("setting up routing: %w", err)
 	}
 	defer func() {
 		routingLogger.Info("routing cleanup...")
@@ -339,11 +360,14 @@ func _main(ctx context.Context, buildInfo models.BuildInformation,
 	tickersGroupHandler := goshutdown.NewGroupHandler("tickers", defaultGroupOptions...)
 	otherGroupHandler := goshutdown.NewGroupHandler("other", defaultGroupOptions...)
 
-	pprofReady := make(chan struct{})
-	pprofHandler, pprofCtx, pprofDone := goshutdown.NewGoRoutineHandler("pprof server")
-	go pprofServer.Run(pprofCtx, pprofReady, pprofDone)
-	otherGroupHandler.Add(pprofHandler)
-	<-pprofReady
+	if *allSettings.Pprof.Enabled {
+		// TODO run in run loop so this can be patched at runtime
+		pprofReady := make(chan struct{})
+		pprofHandler, pprofCtx, pprofDone := goshutdown.NewGoRoutineHandler("pprof server")
+		go pprofServer.Run(pprofCtx, pprofReady, pprofDone)
+		otherGroupHandler.Add(pprofHandler)
+		<-pprofReady
+	}
 
 	portForwardLogger := logger.New(log.SetComponent("port forwarding"))
 	portForwardLooper := portforward.NewLoop(allSettings.VPN.Provider.PortForwarding,
@@ -389,7 +413,7 @@ func _main(ctx context.Context, buildInfo models.BuildInformation,
 		httpClient, unzipper, parallelResolver, ipFetcher, openvpnFileExtractor)
 
 	vpnLogger := logger.New(log.SetComponent("vpn"))
-	vpnLooper := vpn.NewLoop(allSettings.VPN, allSettings.Firewall.VPNInputPorts,
+	vpnLooper := vpn.NewLoop(allSettings.VPN, ipv6Supported, allSettings.Firewall.VPNInputPorts,
 		providers, storage, ovpnConf, netLinker, firewallConf, routingConf, portForwardLooper,
 		cmder, publicIPLooper, unboundLooper, vpnLogger, httpClient,
 		buildInfo, *allSettings.Version.Enabled)
@@ -431,9 +455,10 @@ func _main(ctx context.Context, buildInfo models.BuildInformation,
 		"http server", goroutine.OptionTimeout(defaultShutdownTimeout))
 	httpServer, err := server.New(httpServerCtx, controlServerAddress, controlServerLogging,
 		logger.New(log.SetComponent("http server")),
-		buildInfo, vpnLooper, portForwardLooper, unboundLooper, updaterLooper, publicIPLooper, storage)
+		buildInfo, vpnLooper, portForwardLooper, unboundLooper, updaterLooper, publicIPLooper,
+		storage, ipv6Supported)
 	if err != nil {
-		return fmt.Errorf("cannot setup control server: %w", err)
+		return fmt.Errorf("setting up control server: %w", err)
 	}
 	httpServerReady := make(chan struct{})
 	go httpServer.Run(httpServerCtx, httpServerReady, httpServerDone)
@@ -480,7 +505,7 @@ func printVersions(ctx context.Context, logger infoer,
 	for _, element := range elements {
 		version, err := element.getVersion(ctx)
 		if err != nil {
-			return err
+			return fmt.Errorf("getting %s version: %w", element.name, err)
 		}
 		logger.Info(element.name + " version: " + version)
 	}
@@ -494,6 +519,8 @@ type netLinker interface {
 	Ruler
 	Linker
 	IsWireguardSupported() (ok bool, err error)
+	IsIPv6Supported() (ok bool, err error)
+	PatchLoggerLevel(level log.Level)
 }
 
 type Addresser interface {
@@ -529,8 +556,8 @@ type Linker interface {
 type clier interface {
 	ClientKey(args []string) error
 	FormatServers(args []string) error
-	OpenvpnConfig(logger cli.OpenvpnConfigLogger, source sources.Source) error
-	HealthCheck(ctx context.Context, source sources.Source, warner cli.Warner) error
+	OpenvpnConfig(logger cli.OpenvpnConfigLogger, source cli.Source, ipv6Checker cli.IPv6Checker) error
+	HealthCheck(ctx context.Context, source cli.Source, warner cli.Warner) error
 	Update(ctx context.Context, args []string, logger cli.UpdaterLogger) error
 }
 
@@ -538,3 +565,9 @@ type Tun interface {
 	Check(tunDevice string) error
 	Create(tunDevice string) error
 }
+
+type Source interface {
+	Read() (settings settings.Settings, err error)
+	ReadHealth() (health settings.Health, err error)
+	String() string
+}

go.mod

@@ -1,10 +1,10 @@
 module github.com/qdm12/gluetun
 
-go 1.17
+go 1.20
 
 require (
-	github.com/breml/rootcerts v0.2.6
-	github.com/fatih/color v1.13.0
+	github.com/breml/rootcerts v0.2.10
+	github.com/fatih/color v1.14.1
 	github.com/golang/mock v1.6.0
 	github.com/qdm12/dns v1.11.0
 	github.com/qdm12/golibs v0.0.0-20210822203818-5c568b0777b6
@@ -15,31 +15,35 @@ require (
 	github.com/qdm12/log v0.1.0
 	github.com/qdm12/ss-server v0.4.0
 	github.com/qdm12/updated v0.0.0-20210603204757-205acfe6937e
-	github.com/stretchr/testify v1.8.0
+	github.com/stretchr/testify v1.8.2
 	github.com/vishvananda/netlink v1.1.1-0.20211129163951-9ada19101fc5
-	golang.org/x/net v0.0.0-20210916014120-12bc252f5db8
-	golang.org/x/sys v0.0.0-20210630005230-0f9fa26af87c
-	golang.org/x/text v0.3.7
-	golang.zx2c4.com/wireguard v0.0.0-20210805125648-3957e9b9dd19
-	golang.zx2c4.com/wireguard/wgctrl v0.0.0-20210803171230-4253848d036c
+	github.com/youmark/pkcs8 v0.0.0-20201027041543-1326539a0a0a
+	golang.org/x/net v0.0.0-20220418201149-a630d4f3e7a2
+	golang.org/x/sys v0.6.0
+	golang.org/x/text v0.8.0
+	golang.zx2c4.com/wireguard v0.0.0-20220703234212-c31a7b1ab478
+	golang.zx2c4.com/wireguard/wgctrl v0.0.0-20220504211119-3d4a969bb56b
 	inet.af/netaddr v0.0.0-20210718074554-06ca8145d722
 )
 
 require (
 	github.com/davecgh/go-spew v1.1.1 // indirect
-	github.com/google/go-cmp v0.5.5 // indirect
-	github.com/josharian/native v0.0.0-20200817173448-b6b71def0850 // indirect
-	github.com/mattn/go-colorable v0.1.9 // indirect
-	github.com/mattn/go-isatty v0.0.14 // indirect
-	github.com/mdlayher/genetlink v1.0.0 // indirect
-	github.com/mdlayher/netlink v1.4.0 // indirect
+	github.com/google/go-cmp v0.5.7 // indirect
+	github.com/josharian/native v1.0.0 // indirect
+	github.com/mattn/go-colorable v0.1.13 // indirect
+	github.com/mattn/go-isatty v0.0.17 // indirect
+	github.com/mdlayher/genetlink v1.2.0 // indirect
+	github.com/mdlayher/netlink v1.6.0 // indirect
+	github.com/mdlayher/socket v0.2.3 // indirect
 	github.com/miekg/dns v1.1.40 // indirect
 	github.com/mr-tron/base58 v1.2.0 // indirect
 	github.com/pmezard/go-difflib v1.0.0 // indirect
 	github.com/riobard/go-bloom v0.0.0-20200614022211-cdc8013cb5b3 // indirect
 	github.com/vishvananda/netns v0.0.0-20200728191858-db3c7e526aae // indirect
 	go4.org/intern v0.0.0-20210108033219-3eb7198706b2 // indirect
-	go4.org/unsafe/assume-no-moving-gc v0.0.0-20220617031537-928513b29760 // indirect
-	golang.org/x/crypto v0.0.0-20210711020723-a769d52b0f97 // indirect
+	go4.org/unsafe/assume-no-moving-gc v0.0.0-20230221090011-e4bae7ad2296 // indirect
+	golang.org/x/crypto v0.0.0-20220411220226-7b82a4e95df4 // indirect
+	golang.org/x/sync v0.0.0-20210220032951-036812b2e83c // indirect
+	golang.zx2c4.com/wintun v0.0.0-20211104114900-415007cec224 // indirect
 	gopkg.in/yaml.v3 v3.0.1 // indirect
 )

go.sum

@@ -4,8 +4,8 @@ github.com/alcortesm/tgz v0.0.0-20161220082320-9c5fe88206d7/go.mod h1:6zEj6s6u/g
 github.com/anmitsu/go-shlex v0.0.0-20161002113705-648efa622239/go.mod h1:2FmKhYUyUczH0OGQWaF5ceTx0UBShxjsH6f8oGKYe2c=
 github.com/armon/go-socks5 v0.0.0-20160902184237-e75332964ef5/go.mod h1:wHh0iHkYZB8zMSxRWpUBQtwG5a7fFgvEO+odwuTv2gs=
 github.com/asaskevich/govalidator v0.0.0-20180720115003-f9ffefc3facf/go.mod h1:lB+ZfQJz7igIIfQNfa7Ml4HSf2uFQQRzpGGRXenZAgY=
-github.com/breml/rootcerts v0.2.6 h1:CdPczjzItec+wopLoDsBAFcLEai2q7Yayfg/94/q/2E=
-github.com/breml/rootcerts v0.2.6/go.mod h1:24FDtzYMpqIeYC7QzaE8VPRQaFZU5TIUDlyk8qwjD88=
+github.com/breml/rootcerts v0.2.10 h1:UGVZ193UTSUASpGtg6pbDwzOd7XQP+at0Ssg1/2E4h8=
+github.com/breml/rootcerts v0.2.10/go.mod h1:24FDtzYMpqIeYC7QzaE8VPRQaFZU5TIUDlyk8qwjD88=
 github.com/creack/pty v1.1.7/go.mod h1:lj5s0c3V2DBrqTV7llrYr5NG6My20zk30Fl46Y7DoTY=
 github.com/davecgh/go-spew v1.1.0/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
 github.com/davecgh/go-spew v1.1.1 h1:vj9j/u1bqnvCEfJOwUhtlOARqs3+rkHYY13jYWTU97c=
@@ -14,8 +14,8 @@ github.com/docker/go-units v0.3.3/go.mod h1:fgPhTUdO+D/Jk86RDLlptpiXQzgHJF7gydDD
 github.com/dvyukov/go-fuzz v0.0.0-20210103155950-6a8e9d1f2415/go.mod h1:11Gm+ccJnvAhCNLlf5+cS9KjtbaD5I5zaZpFMsTHWTw=
 github.com/emirpasic/gods v1.12.0/go.mod h1:YfzfFFoVP/catgzJb4IKIqXjX78Ha8FMSDh3ymbK86o=
 github.com/fatih/color v1.12.0/go.mod h1:ELkj/draVOlAH/xkhN6mQ50Qd0MPOk5AAr3maGEBuJM=
-github.com/fatih/color v1.13.0 h1:8LOYc1KYPPmyKMuN8QV2DNRWNbLo6LZ0iLs8+mlH53w=
-github.com/fatih/color v1.13.0/go.mod h1:kLAiJbzzSOZDVNGyDpeOxJ47H46qBXwg5ILebYFFOfk=
+github.com/fatih/color v1.14.1 h1:qfhVLaG5s+nCROl1zJsZRxFeYrHLqWroPOQ8BWiNb4w=
+github.com/fatih/color v1.14.1/go.mod h1:2oHN61fhTpgcxD3TSWCgKDiH1+x4OiDVVGH8WlgGZGg=
 github.com/flynn/go-shlex v0.0.0-20150515145356-3f9db97f8568/go.mod h1:xEzjJPgXI435gkrCt3MPfRiAkVrwSbHsst4LCFVfpJc=
 github.com/gliderlabs/ssh v0.2.2/go.mod h1:U7qILu1NlMHj9FlMhZLlkCdDnU1DBEAqr0aevW3Awn0=
 github.com/globalsign/mgo v0.0.0-20180905125535-1ca0a4f7cbcb/go.mod h1:xkRDCp4j0OGD1HRkm4kmhM+pmpv3AKq5SU7GMg4oO/Q=
@@ -36,28 +36,16 @@ github.com/golang/mock v1.5.0/go.mod h1:CWnOUgYIOo4TcNZ0wHX3YZCqsaM1I1Jvs6v3mP3K
 github.com/golang/mock v1.6.0 h1:ErTB+efbowRARo13NNdxyJji2egdxLGQhRaY+DUumQc=
 github.com/golang/mock v1.6.0/go.mod h1:p6yTPP+5HYm5mzsMV8JkE6ZKdX+/wYM6Hr+LicevLPs=
 github.com/gomodule/redigo v2.0.0+incompatible/go.mod h1:B4C85qUVwatsJoIUNIfCRsp7qO0iAmpGFZ4EELWSbC4=
-github.com/google/go-cmp v0.2.0/go.mod h1:oXzfMopK8JAjlY9xF4vHSVASa0yLyX7SntLO5aqRK0M=
 github.com/google/go-cmp v0.3.0/go.mod h1:8QqcDgzrUqlUb/G2PQTWiueGozuR1884gddMywk6iLU=
-github.com/google/go-cmp v0.3.1/go.mod h1:8QqcDgzrUqlUb/G2PQTWiueGozuR1884gddMywk6iLU=
-github.com/google/go-cmp v0.4.0/go.mod h1:v8dTdLbMG2kIc/vJvl+f65V22dbkXbowE6jgT/gNBxE=
-github.com/google/go-cmp v0.5.2/go.mod h1:v8dTdLbMG2kIc/vJvl+f65V22dbkXbowE6jgT/gNBxE=
-github.com/google/go-cmp v0.5.4/go.mod h1:v8dTdLbMG2kIc/vJvl+f65V22dbkXbowE6jgT/gNBxE=
-github.com/google/go-cmp v0.5.5 h1:Khx7svrCpmxxtHBq5j2mp/xVjsi8hQMfNLvJFAlrGgU=
-github.com/google/go-cmp v0.5.5/go.mod h1:v8dTdLbMG2kIc/vJvl+f65V22dbkXbowE6jgT/gNBxE=
+github.com/google/go-cmp v0.5.6/go.mod h1:v8dTdLbMG2kIc/vJvl+f65V22dbkXbowE6jgT/gNBxE=
+github.com/google/go-cmp v0.5.7 h1:81/ik6ipDQS2aGcBfIN5dHDB36BwrStyeAQquSYCV4o=
+github.com/google/go-cmp v0.5.7/go.mod h1:n+brtR0CgQNWTVd5ZUFpTBC8YFBDLK/h/bpaJ8/DtOE=
 github.com/google/uuid v1.0.0/go.mod h1:TIyPZe4MgqvfeYDBFedMoGGpEw/LqOeaOT+nhxU+yHo=
 github.com/gotify/go-api-client/v2 v2.0.4/go.mod h1:VKiah/UK20bXsr0JObE1eBVLW44zbBouzjuri9iwjFU=
 github.com/jbenet/go-context v0.0.0-20150711004518-d14ea06fba99/go.mod h1:1lJo3i6rXxKeerYnT8Nvf0QmHCRC1n8sfWVwXF2Frvo=
 github.com/jessevdk/go-flags v1.4.0/go.mod h1:4FA24M0QyGHXBuZZK/XkWh8h0e1EYbRYJSGM75WSRxI=
-github.com/josharian/native v0.0.0-20200817173448-b6b71def0850 h1:uhL5Gw7BINiiPAo24A2sxkcDI0Jt/sqp1v5xQCniEFA=
-github.com/josharian/native v0.0.0-20200817173448-b6b71def0850/go.mod h1:7X/raswPFr05uY3HiLlYeyQntB6OO7E/d2Cu7qoaN2w=
-github.com/jsimonetti/rtnetlink v0.0.0-20190606172950-9527aa82566a/go.mod h1:Oz+70psSo5OFh8DBl0Zv2ACw7Esh6pPUphlvZG9x7uw=
-github.com/jsimonetti/rtnetlink v0.0.0-20200117123717-f846d4f6c1f4/go.mod h1:WGuG/smIU4J/54PblvSbh+xvCZmpJnFgr3ds6Z55XMQ=
-github.com/jsimonetti/rtnetlink v0.0.0-20201009170750-9c6f07d100c1/go.mod h1:hqoO/u39cqLeBLebZ8fWdE96O7FxrAsRYhnVOdgHxok=
-github.com/jsimonetti/rtnetlink v0.0.0-20201216134343-bde56ed16391/go.mod h1:cR77jAZG3Y3bsb8hF6fHJbFoyFukLFOkQ98S0pQz3xw=
-github.com/jsimonetti/rtnetlink v0.0.0-20201220180245-69540ac93943/go.mod h1:z4c53zj6Eex712ROyh8WI0ihysb5j2ROyV42iNogmAs=
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 golang.org/x/sync v0.0.0-20190423024810-112230192c58/go.mod h1:RxMgew5VJxzue5/jJTE5uejpjVlOe/izrB70Jof72aM=
 golang.org/x/sync v0.0.0-20201020160332-67f06af15bc9/go.mod h1:RxMgew5VJxzue5/jJTE5uejpjVlOe/izrB70Jof72aM=
 golang.org/x/sync v0.0.0-20210220032951-036812b2e83c h1:5KslGYwFpkhGh+Q16bwMP3cOontH8FOep7tGV86Y7SQ=
 golang.org/x/sync v0.0.0-20210220032951-036812b2e83c/go.mod h1:RxMgew5VJxzue5/jJTE5uejpjVlOe/izrB70Jof72aM=
 golang.org/x/sys v0.0.0-20190215142949-d0b11bdaac8a/go.mod h1:STP8DvDyc/dI5b8T5hshtkjS+E42TnysNCUPdjciGhY=
 golang.org/x/sys v0.0.0-20190221075227-b4e8571b14e0/go.mod h1:STP8DvDyc/dI5b8T5hshtkjS+E42TnysNCUPdjciGhY=
-golang.org/x/sys v0.0.0-20190312061237-fead79001313/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
-golang.org/x/sys v0.0.0-20190411185658-b44545bcd369/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
 golang.org/x/sys v0.0.0-20190412213103-97732733099d/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
 golang.org/x/sys v0.0.0-20190726091711-fc99dfbffb4e/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
-golang.org/x/sys v0.0.0-20190826190057-c7b8b68b1456/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
 golang.org/x/sys v0.0.0-20190924154521-2837fb4f24fe/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
-golang.org/x/sys v0.0.0-20191008105621-543471e840be/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
-golang.org/x/sys v0.0.0-20191026070338-33540a1f6037/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
 golang.org/x/sys v0.0.0-20200116001909-b77594299b42/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
-golang.org/x/sys v0.0.0-20200202164722-d101bd2416d5/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
 golang.org/x/sys v0.0.0-20200217220822-9197077df867/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
 golang.org/x/sys v0.0.0-20200223170610-d5e6a3e2c0ae/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
 golang.org/x/sys v0.0.0-20200728102440-3e129f6d46b1/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
 golang.org/x/sys v0.0.0-20200930185726-fdedc70b468f/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
-golang.org/x/sys v0.0.0-20201009025420-dfb3f7c4e634/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
-golang.org/x/sys v0.0.0-20201118182958-a01c418693c7/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
 golang.org/x/sys v0.0.0-20201119102817-f84b799fce68/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
-golang.org/x/sys v0.0.0-20201218084310-7d0127a74742/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
-golang.org/x/sys v0.0.0-20210110051926-789bb1bd4061/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
 golang.org/x/sys v0.0.0-20210119212857-b64e53b001e4/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
-golang.org/x/sys v0.0.0-20210123111255-9b0068b26619/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
-golang.org/x/sys v0.0.0-20210124154548-22da62e12c0c/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
-golang.org/x/sys v0.0.0-20210216163648-f7da38b97c65/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
-golang.org/x/sys v0.0.0-20210309040221-94ec62e08169/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
 golang.org/x/sys v0.0.0-20210330210617-4fbd30eecc44/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
-golang.org/x/sys v0.0.0-20210403161142-5e06dd20ab57/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
 golang.org/x/sys v0.0.0-20210423082822-04245dca01da/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
-golang.org/x/sys v0.0.0-20210503173754-0981d6026fa6/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
 golang.org/x/sys v0.0.0-20210510120138-977fb7262007/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
 golang.org/x/sys v0.0.0-20210615035016-665e8c7367d1/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
-golang.org/x/sys v0.0.0-20210630005230-0f9fa26af87c h1:F1jZWGFhYfh0Ci55sIpILtKKK8p3i2/krTr0H1rg74I=
-golang.org/x/sys v0.0.0-20210630005230-0f9fa26af87c/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
-golang.org/x/term v0.0.0-20201117132131-f5c789dd3221/go.mod h1:Nr5EML6q2oocZ2LXRh80K7BxOlk5/8JxuGnuhpl+muw=
+golang.org/x/sys v0.0.0-20210927094055-39ccf1dd6fa6/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
+golang.org/x/sys v0.0.0-20211216021012-1d35b9e2eb4e/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
+golang.org/x/sys v0.0.0-20220128215802-99c3d69c2c27/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
+golang.org/x/sys v0.0.0-20220811171246-fbc7d0a398ab/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
+golang.org/x/sys v0.6.0 h1:MVltZSvRTcU2ljQOhs94SXPftV6DCNnZViHeQps87pQ=
+golang.org/x/sys v0.6.0/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
 golang.org/x/term v0.0.0-20201126162022-7de9c90e9dd1/go.mod h1:bj7SfCRtBDWHUb9snDiAeCFNEtKQo2Wmx5Cou7ajbmo=
+golang.org/x/term v0.0.0-20210927222741-03fcf44c2211/go.mod h1:jbD1KX2456YbFQfuXm/mYQcufACuNUgVhRMnK/tPxf8=
 golang.org/x/text v0.3.0/go.mod h1:NqM8EUOU14njkJ3fqMW+pc6Ldnwhi/IjpwHt7yyuwOQ=
 golang.org/x/text v0.3.2/go.mod h1:bEr9sfX3Q8Zfm5fL9x+3itogRgK3+ptLWKqgva+5dAk=
 golang.org/x/text v0.3.3/go.mod h1:5Zoc/QRtKVWzQhOtBMvqHzDpF6irO9z98xDceosuGiQ=
 golang.org/x/text v0.3.6/go.mod h1:5Zoc/QRtKVWzQhOtBMvqHzDpF6irO9z98xDceosuGiQ=
-golang.org/x/text v0.3.7 h1:olpwvP2KacW1ZWvsR7uQhoyTYvKAupfQrRGBFM352Gk=
 golang.org/x/text v0.3.7/go.mod h1:u+2+/6zg+i71rQMx5EYifcz6MCKuco9NR6JIITiCfzQ=
+golang.org/x/text v0.8.0 h1:57P1ETyNKtuIjB4SRd15iJxuhj8Gc416Y78H3qgMh68=
+golang.org/x/text v0.8.0/go.mod h1:e1OnstbJyHTd6l/uOt8jFFHp6TRDWZR/bV3emEE/zU8=
 golang.org/x/tools v0.0.0-20180917221912-90fa682c2a6e/go.mod h1:n7NCudcB/nEzxVGmLbDWY5pfWTLqBcC2KZ6jyYvM4mQ=
 golang.org/x/tools v0.0.0-20190729092621-ff9f1409240a/go.mod h1:jcCCGcm9btYwXyDqrUWc6MKQKKGJCWEQ3AfLSRIbEuI=
 golang.org/x/tools v0.0.0-20191119224855-298f0cb1881e/go.mod h1:b+2E5dAYhXwXZwtnZ6UAqBI28+e2cm9otk0dWdXHAEo=
@@ -239,11 +205,12 @@ golang.org/x/xerrors v0.0.0-20191011141410-1b5146add898/go.mod h1:I/5z698sn9Ka8T
 golang.org/x/xerrors v0.0.0-20191204190536-9bdfabe68543/go.mod h1:I/5z698sn9Ka8TeJc9MKroUUfqBBauWjQqLJ2OPfmY0=
 golang.org/x/xerrors v0.0.0-20200804184101-5ec99f83aff1 h1:go1bK/D/BFZV2I8cIQd1NKEZ+0owSTG1fDTci4IqFcE=
 golang.org/x/xerrors v0.0.0-20200804184101-5ec99f83aff1/go.mod h1:I/5z698sn9Ka8TeJc9MKroUUfqBBauWjQqLJ2OPfmY0=
-golang.zx2c4.com/wireguard v0.0.0-20210427022245-097af6e1351b/go.mod h1:a057zjmoc00UN7gVkaJt2sXVK523kMJcogDTEvPIasg=
-golang.zx2c4.com/wireguard v0.0.0-20210805125648-3957e9b9dd19 h1:ab2jcw2W91Rz07eHAb8Lic7sFQKO0NhBftjv6m/gL/0=
-golang.zx2c4.com/wireguard v0.0.0-20210805125648-3957e9b9dd19/go.mod h1:laHzsbfMhGSobUmruXWAyMKKHSqvIcrqZJMyHD+/3O8=
-golang.zx2c4.com/wireguard/wgctrl v0.0.0-20210803171230-4253848d036c h1:ADNrRDI5NR23/TUCnEmlLZLt4u9DnZ2nwRkPrAcFvto=
-golang.zx2c4.com/wireguard/wgctrl v0.0.0-20210803171230-4253848d036c/go.mod h1:+1XihzyZUBJcSc5WO9SwNA7v26puQwOEDwanaxfNXPQ=
+golang.zx2c4.com/wintun v0.0.0-20211104114900-415007cec224 h1:Ug9qvr1myri/zFN6xL17LSCBGFDnphBBhzmILHsM5TY=
+golang.zx2c4.com/wintun v0.0.0-20211104114900-415007cec224/go.mod h1:deeaetjYA+DHMHg+sMSMI58GrEteJUUzzw7en6TJQcI=
+golang.zx2c4.com/wireguard v0.0.0-20220703234212-c31a7b1ab478 h1:vDy//hdR+GnROE3OdYbQKt9rdtNdHkDtONvpRwmls/0=
+golang.zx2c4.com/wireguard v0.0.0-20220703234212-c31a7b1ab478/go.mod h1:bVQfyl2sCM/QIIGHpWbFGfHPuDvqnCNkT6MQLTCjO/U=
+golang.zx2c4.com/wireguard/wgctrl v0.0.0-20220504211119-3d4a969bb56b h1:9JncmKXcUwE918my+H6xmjBdhK2jM/UTUNXxhRG1BAk=
+golang.zx2c4.com/wireguard/wgctrl v0.0.0-20220504211119-3d4a969bb56b/go.mod h1:yp4gl6zOlnDGOZeWeDfMwQcsdOIQnMdhuPx9mwwWBL4=
 gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405/go.mod h1:Co6ibVJAznAaIkqp8huTwlJQCZ016jof/cbN4VW5Yz0=
 gopkg.in/check.v1 v1.0.0-20180628173108-788fd7840127 h1:qIbj1fsPNlZgppZ+VLlY7N33q108Sa+fhmuc+sWQYwY=
 gopkg.in/check.v1 v1.0.0-20180628173108-788fd7840127/go.mod h1:Co6ibVJAznAaIkqp8huTwlJQCZ016jof/cbN4VW5Yz0=

internal/cli/formatservers.go

@@ -73,7 +73,7 @@ func (c *CLI) FormatServers(args []string) error {
 	logger := newNoopLogger()
 	storage, err := storage.New(logger, constants.ServersData)
 	if err != nil {
-		return fmt.Errorf("cannot create servers storage: %w", err)
+		return fmt.Errorf("creating servers storage: %w", err)
 	}
 
 	formatted := storage.FormatToMarkdown(providerToFormat)
@@ -81,18 +81,18 @@ func (c *CLI) FormatServers(args []string) error {
 	output = filepath.Clean(output)
 	file, err := os.OpenFile(output, os.O_TRUNC|os.O_WRONLY|os.O_CREATE, 0644)
 	if err != nil {
-		return fmt.Errorf("cannot open output file: %w", err)
+		return fmt.Errorf("opening output file: %w", err)
 	}
 
 	_, err = fmt.Fprint(file, formatted)
 	if err != nil {
 		_ = file.Close()
-		return fmt.Errorf("cannot write to output file: %w", err)
+		return fmt.Errorf("writing to output file: %w", err)
 	}
 
 	err = file.Close()
 	if err != nil {
-		return fmt.Errorf("cannot close output file: %w", err)
+		return fmt.Errorf("closing output file: %w", err)
 	}
 
 	return nil

internal/cli/healthcheck.go

@@ -6,17 +6,18 @@ import (
 	"net/http"
 	"time"
 
-	"github.com/qdm12/gluetun/internal/configuration/sources"
 	"github.com/qdm12/gluetun/internal/healthcheck"
 )
 
-func (c *CLI) HealthCheck(ctx context.Context, source sources.Source, warner Warner) error {
+func (c *CLI) HealthCheck(ctx context.Context, source Source, warner Warner) error {
 	// Extract the health server port from the configuration.
 	config, err := source.ReadHealth()
 	if err != nil {
 		return err
 	}
 
+	config.SetDefaults()
+
 	err = config.Validate()
 	if err != nil {
 		return err

internal/cli/interfaces.go

@@ -1,9 +1,9 @@
-package sources
+package cli
 
 import "github.com/qdm12/gluetun/internal/configuration/settings"
 
 type Source interface {
 	Read() (settings settings.Settings, err error)
-	ReadHealth() (settings settings.Health, err error)
+	ReadHealth() (health settings.Health, err error)
 	String() string
 }

internal/cli/openvpnconfig.go

@@ -8,7 +8,6 @@ import (
 	"strings"
 	"time"
 
-	"github.com/qdm12/gluetun/internal/configuration/sources"
 	"github.com/qdm12/gluetun/internal/constants"
 	"github.com/qdm12/gluetun/internal/openvpn/extract"
 	"github.com/qdm12/gluetun/internal/provider"
@@ -36,7 +35,12 @@ type IPFetcher interface {
 	FetchMultiInfo(ctx context.Context, ips []net.IP) (data []ipinfo.Response, err error)
 }
 
-func (c *CLI) OpenvpnConfig(logger OpenvpnConfigLogger, source sources.Source) error {
+type IPv6Checker interface {
+	IsIPv6Supported() (supported bool, err error)
+}
+
+func (c *CLI) OpenvpnConfig(logger OpenvpnConfigLogger, source Source,
+	ipv6Checker IPv6Checker) error {
 	storage, err := storage.New(logger, constants.ServersData)
 	if err != nil {
 		return err
@@ -47,8 +51,13 @@ func (c *CLI) OpenvpnConfig(logger OpenvpnConfigLogger, source sources.Source) e
 		return err
 	}
 
-	if err = allSettings.Validate(storage); err != nil {
-		return err
+	ipv6Supported, err := ipv6Checker.IsIPv6Supported()
+	if err != nil {
+		return fmt.Errorf("checking for IPv6 support: %w", err)
+	}
+
+	if err = allSettings.Validate(storage, ipv6Supported); err != nil {
+		return fmt.Errorf("validating settings: %w", err)
 	}
 
 	// Unused by this CLI command
@@ -62,12 +71,14 @@ func (c *CLI) OpenvpnConfig(logger OpenvpnConfigLogger, source sources.Source) e
 	providers := provider.NewProviders(storage, time.Now, warner, client,
 		unzipper, parallelResolver, ipFetcher, openvpnFileExtractor)
 	providerConf := providers.Get(*allSettings.VPN.Provider.Name)
-	connection, err := providerConf.GetConnection(allSettings.VPN.Provider.ServerSelection)
+	connection, err := providerConf.GetConnection(
+		allSettings.VPN.Provider.ServerSelection, ipv6Supported)
 	if err != nil {
 		return err
 	}
 
-	lines := providerConf.OpenVPNConfig(connection, allSettings.VPN.OpenVPN)
+	lines := providerConf.OpenVPNConfig(connection,
+		allSettings.VPN.OpenVPN, ipv6Supported)
 
 	fmt.Println(strings.Join(lines, "\n"))
 	return nil

internal/cli/update.go

@@ -72,7 +72,7 @@ func (c *CLI) Update(ctx context.Context, args []string, logger UpdaterLogger) e
 
 	storage, err := storage.New(logger, constants.ServersData)
 	if err != nil {
-		return fmt.Errorf("cannot create servers storage: %w", err)
+		return fmt.Errorf("creating servers storage: %w", err)
 	}
 
 	const clientTimeout = 10 * time.Second
@@ -88,13 +88,13 @@ func (c *CLI) Update(ctx context.Context, args []string, logger UpdaterLogger) e
 	updater := updater.New(httpClient, storage, providers, logger)
 	err = updater.UpdateServers(ctx, options.Providers, options.MinRatio)
 	if err != nil {
-		return fmt.Errorf("cannot update server information: %w", err)
+		return fmt.Errorf("updating server information: %w", err)
 	}
 
 	if maintainerMode {
 		err := storage.FlushToFile(c.repoServersPath)
 		if err != nil {
-			return fmt.Errorf("cannot write servers data to embedded JSON file: %w", err)
+			return fmt.Errorf("writing servers data to embedded JSON file: %w", err)
 		}
 	}
 

internal/configuration/settings/dns.go

@@ -31,7 +31,7 @@ type DNS struct {
 func (d DNS) validate() (err error) {
 	err = d.DoT.validate()
 	if err != nil {
-		return fmt.Errorf("failed validating DoT settings: %w", err)
+		return fmt.Errorf("validating DoT settings: %w", err)
 	}
 
 	return nil

internal/configuration/settings/errors.go

@@ -37,10 +37,13 @@ var (
 	ErrWireguardEndpointIPNotSet       = errors.New("endpoint IP is not set")
 	ErrWireguardEndpointPortNotAllowed = errors.New("endpoint port is not allowed")
 	ErrWireguardEndpointPortNotSet     = errors.New("endpoint port is not set")
+	ErrWireguardEndpointPortSet        = errors.New("endpoint port is set")
 	ErrWireguardInterfaceAddressNotSet = errors.New("interface address is not set")
+	ErrWireguardInterfaceAddressIPv6   = errors.New("interface address is IPv6 but IPv6 is not supported")
 	ErrWireguardInterfaceNotValid      = errors.New("interface name is not valid")
 	ErrWireguardPreSharedKeyNotSet     = errors.New("pre-shared key is not set")
 	ErrWireguardPrivateKeyNotSet       = errors.New("private key is not set")
 	ErrWireguardPublicKeyNotSet        = errors.New("public key is not set")
 	ErrWireguardPublicKeyNotValid      = errors.New("public key is not valid")
+	ErrWireguardImplementationNotValid = errors.New("implementation is not valid")
 )

internal/configuration/settings/firewall.go

@@ -109,7 +109,8 @@ func (f Firewall) toLinesNode() (node *gotree.Node) {
 	if len(f.OutboundSubnets) > 0 {
 		outboundSubnets := node.Appendf("Outbound subnets:")
 		for _, subnet := range f.OutboundSubnets {
-			outboundSubnets.Appendf("%s", subnet)
+			subnet := subnet
+			outboundSubnets.Appendf("%s", &subnet)
 		}
 	}
 

internal/configuration/settings/openvpn.go

@@ -42,18 +42,18 @@ type OpenVPN struct {
 	// It cannot be nil in the internal state.
 	// It is ignored if it is set to the empty string.
 	Auth *string
-	// Cert is the OpenVPN certificate for the <cert> block.
+	// Cert is the base64 encoded DER of an OpenVPN certificate for the <cert> block.
 	// This is notably used by Cyberghost and VPN secure.
 	// It can be set to the empty string to be ignored.
 	// It cannot be nil in the internal state.
 	Cert *string
-	// Key is the OpenVPN key.
+	// Key is the base64 encoded DER of an OpenVPN key.
 	// This is used by Cyberghost and VPN Unlimited.
 	// It can be set to the empty string to be ignored.
 	// It cannot be nil in the internal state.
 	Key *string
-	// EncryptedKey is the content of an encrypted
-	// key for OpenVPN. It is used by VPN secure.
+	// EncryptedKey is the base64 encoded DER of an encrypted key for OpenVPN.
+	// It is used by VPN secure.
 	// It defaults to the empty string meaning it is not
 	// to be used. KeyPassphrase must be set if this one is set.
 	EncryptedKey *string
@@ -65,10 +65,6 @@ type OpenVPN struct {
 	// Private Internet Access. It can be set to an
 	// empty string for other providers.
 	PIAEncPreset *string
-	// IPv6 is set to true if IPv6 routing should be
-	// set to be tunnel in OpenVPN, and false otherwise.
-	// It cannot be nil in the internal state.
-	IPv6 *bool // TODO automate like with Wireguard
 	// MSSFix is the value (1 to 10000) to set for the
 	// mssfix option for OpenVPN. It is ignored if set to 0.
 	// It cannot be nil in the internal state.
@@ -99,12 +95,15 @@ func (o OpenVPN) validate(vpnProvider string) (err error) {
 	}
 
 	isCustom := vpnProvider == providers.Custom
+	isUserRequired := !isCustom &&
+		vpnProvider != providers.Airvpn &&
+		vpnProvider != providers.VPNSecure
 
-	if !isCustom && *o.User == "" {
+	if isUserRequired && *o.User == "" {
 		return ErrOpenVPNUserIsEmpty
 	}
 
-	passwordRequired := !isCustom &&
+	passwordRequired := isUserRequired &&
 		(vpnProvider != providers.Ivpn || !ivpnAccountID.MatchString(*o.User))
 
 	if passwordRequired && *o.Password == "" {
@@ -172,7 +171,7 @@ func validateOpenVPNConfigFilepath(isCustom bool,
 	extractor := extract.New()
 	_, _, err = extractor.Data(confFile)
 	if err != nil {
-		return fmt.Errorf("failed extracting information from custom configuration file: %w", err)
+		return fmt.Errorf("extracting information from custom configuration file: %w", err)
 	}
 
 	return nil
@@ -182,6 +181,7 @@ func validateOpenVPNClientCertificate(vpnProvider,
 	clientCert string) (err error) {
 	switch vpnProvider {
 	case
+		providers.Airvpn,
 		providers.Cyberghost,
 		providers.VPNSecure,
 		providers.VPNUnlimited:
@@ -204,6 +204,7 @@ func validateOpenVPNClientCertificate(vpnProvider,
 func validateOpenVPNClientKey(vpnProvider, clientKey string) (err error) {
 	switch vpnProvider {
 	case
+		providers.Airvpn,
 		providers.Cyberghost,
 		providers.VPNUnlimited,
 		providers.Wevpn:
@@ -253,7 +254,6 @@ func (o *OpenVPN) copy() (copied OpenVPN) {
 		EncryptedKey:  helpers.CopyStringPtr(o.EncryptedKey),
 		KeyPassphrase: helpers.CopyStringPtr(o.KeyPassphrase),
 		PIAEncPreset:  helpers.CopyStringPtr(o.PIAEncPreset),
-		IPv6:          helpers.CopyBoolPtr(o.IPv6),
 		MSSFix:        helpers.CopyUint16Ptr(o.MSSFix),
 		Interface:     o.Interface,
 		ProcessUser:   o.ProcessUser,
@@ -276,7 +276,6 @@ func (o *OpenVPN) mergeWith(other OpenVPN) {
 	o.EncryptedKey = helpers.MergeWithStringPtr(o.EncryptedKey, other.EncryptedKey)
 	o.KeyPassphrase = helpers.MergeWithStringPtr(o.KeyPassphrase, other.KeyPassphrase)
 	o.PIAEncPreset = helpers.MergeWithStringPtr(o.PIAEncPreset, other.PIAEncPreset)
-	o.IPv6 = helpers.MergeWithBool(o.IPv6, other.IPv6)
 	o.MSSFix = helpers.MergeWithUint16(o.MSSFix, other.MSSFix)
 	o.Interface = helpers.MergeWithString(o.Interface, other.Interface)
 	o.ProcessUser = helpers.MergeWithString(o.ProcessUser, other.ProcessUser)
@@ -299,7 +298,6 @@ func (o *OpenVPN) overrideWith(other OpenVPN) {
 	o.EncryptedKey = helpers.OverrideWithStringPtr(o.EncryptedKey, other.EncryptedKey)
 	o.KeyPassphrase = helpers.OverrideWithStringPtr(o.KeyPassphrase, other.KeyPassphrase)
 	o.PIAEncPreset = helpers.OverrideWithStringPtr(o.PIAEncPreset, other.PIAEncPreset)
-	o.IPv6 = helpers.OverrideWithBool(o.IPv6, other.IPv6)
 	o.MSSFix = helpers.OverrideWithUint16(o.MSSFix, other.MSSFix)
 	o.Interface = helpers.OverrideWithString(o.Interface, other.Interface)
 	o.ProcessUser = helpers.OverrideWithString(o.ProcessUser, other.ProcessUser)
@@ -328,8 +326,6 @@ func (o *OpenVPN) setDefaults(vpnProvider string) {
 		defaultEncPreset = presets.Strong
 	}
 	o.PIAEncPreset = helpers.DefaultStringPtr(o.PIAEncPreset, defaultEncPreset)
-
-	o.IPv6 = helpers.DefaultBool(o.IPv6, false)
 	o.MSSFix = helpers.DefaultUint16(o.MSSFix, 0)
 	o.Interface = helpers.DefaultString(o.Interface, "tun0")
 	o.ProcessUser = helpers.DefaultString(o.ProcessUser, "root")
@@ -375,8 +371,6 @@ func (o OpenVPN) toLinesNode() (node *gotree.Node) {
 		node.Appendf("Private Internet Access encryption preset: %s", *o.PIAEncPreset)
 	}
 
-	node.Appendf("Tunnel IPv6: %s", helpers.BoolPtrToYesNo(o.IPv6))
-
 	if *o.MSSFix > 0 {
 		node.Appendf("MSS Fix: %d", *o.MSSFix)
 	}

internal/configuration/settings/openvpnselection.go

@@ -67,6 +67,12 @@ func (o OpenVPNSelection) validate(vpnProvider string) (err error) {
 		default:
 			var allowedTCP, allowedUDP []uint16
 			switch vpnProvider {
+			case providers.Airvpn:
+				allowedTCP = []uint16{
+					53, 80, 443, // IP in 1, 3
+					1194, 2018, 41185, // IP in 1, 2, 3, 4
+				}
+				allowedUDP = []uint16{53, 80, 443, 1194, 2018, 41185}
 			case providers.Ivpn:
 				allowedTCP = []uint16{80, 443, 1143}
 				allowedUDP = []uint16{53, 1194, 2049, 2050}

internal/configuration/settings/provider.go

@@ -30,9 +30,11 @@ func (p *Provider) validate(vpnType string, storage Storage) (err error) {
 		validNames = append(validNames, "pia") // Retro-compatibility
 	} else { // Wireguard
 		validNames = []string{
+			providers.Airvpn,
 			providers.Custom,
 			providers.Ivpn,
 			providers.Mullvad,
+			providers.Surfshark,
 			providers.Windscribe,
 		}
 	}

internal/configuration/settings/settings.go

@@ -3,6 +3,10 @@ package settings
 import (
 	"fmt"
 
+	"github.com/qdm12/gluetun/internal/configuration/settings/helpers"
+	"github.com/qdm12/gluetun/internal/constants/openvpn"
+	"github.com/qdm12/gluetun/internal/constants/providers"
+	"github.com/qdm12/gluetun/internal/constants/vpn"
 	"github.com/qdm12/gluetun/internal/models"
 	"github.com/qdm12/gluetun/internal/pprof"
 	"github.com/qdm12/gotree"
@@ -31,7 +35,7 @@ type Storage interface {
 // Validate validates all the settings and returns an error
 // if one of them is not valid.
 // TODO v4 remove pointer for receiver (because of Surfshark).
-func (s *Settings) Validate(storage Storage) (err error) {
+func (s *Settings) Validate(storage Storage, ipv6Supported bool) (err error) {
 	nameToValidation := map[string]func() error{
 		"control server":  s.ControlServer.validate,
 		"dns":             s.DNS.validate,
@@ -46,7 +50,7 @@ func (s *Settings) Validate(storage Storage) (err error) {
 		"version":         s.Version.validate,
 		// Pprof validation done in pprof constructor
 		"VPN": func() error {
-			return s.VPN.Validate(storage)
+			return s.VPN.Validate(storage, ipv6Supported)
 		},
 	}
 
@@ -95,7 +99,7 @@ func (s *Settings) MergeWith(other Settings) {
 }
 
 func (s *Settings) OverrideWith(other Settings,
-	storage Storage) (err error) {
+	storage Storage, ipv6Supported bool) (err error) {
 	patchedSettings := s.copy()
 	patchedSettings.ControlServer.overrideWith(other.ControlServer)
 	patchedSettings.DNS.overrideWith(other.DNS)
@@ -110,7 +114,7 @@ func (s *Settings) OverrideWith(other Settings,
 	patchedSettings.Version.overrideWith(other.Version)
 	patchedSettings.VPN.OverrideWith(other.VPN)
 	patchedSettings.Pprof.OverrideWith(other.Pprof)
-	err = patchedSettings.Validate(storage)
+	err = patchedSettings.Validate(storage, ipv6Supported)
 	if err != nil {
 		return err
 	}
@@ -157,3 +161,37 @@ func (s Settings) toLinesNode() (node *gotree.Node) {
 
 	return node
 }
+
+func (s Settings) Warnings() (warnings []string) {
+	if *s.VPN.Provider.Name == providers.HideMyAss {
+		warnings = append(warnings, "HideMyAss dropped support for Linux OpenVPN "+
+			" so this will likely not work anymore. See https://github.com/qdm12/gluetun/issues/1498.")
+	}
+
+	if helpers.IsOneOf(*s.VPN.Provider.Name, providers.SlickVPN) &&
+		s.VPN.Type == vpn.OpenVPN {
+		if s.VPN.OpenVPN.Version == openvpn.Openvpn24 {
+			warnings = append(warnings, "OpenVPN 2.4 uses OpenSSL 1.1.1 "+
+				"which allows the usage of weak security in today's standards. "+
+				"This can be ok if good security is enforced by the VPN provider. "+
+				"However, "+*s.VPN.Provider.Name+" uses weak security so you should use "+
+				"OpenVPN 2.5 to enforce good security practices.")
+		} else {
+			warnings = append(warnings, "OpenVPN 2.5 uses OpenSSL 3 "+
+				"which prohibits the usage of weak security in today's standards. "+
+				*s.VPN.Provider.Name+" uses weak security which is out "+
+				"of Gluetun's control so the only workaround is to allow such weaknesses "+
+				`using the OpenVPN option tls-cipher "DEFAULT:@SECLEVEL=0". `+
+				"You might want to reach to your provider so they upgrade their certificates. "+
+				"Once this is done, you will have to let the Gluetun maintainers know "+
+				"by creating an issue, attaching the new certificate and we will update Gluetun.")
+		}
+	}
+
+	if s.VPN.OpenVPN.Version == openvpn.Openvpn24 {
+		warnings = append(warnings, "OpenVPN 2.4 will be removed in release v3.34.0 (around June 2023). "+
+			"Please create an issue if you have a compelling reason to keep it.")
+	}
+
+	return warnings
+}

internal/configuration/settings/settings_test.go

@@ -34,7 +34,6 @@ func Test_Settings_String(t *testing.T) {
 |       ├── User: [not set]
 |       ├── Password: [not set]
 |       ├── Private Internet Access encryption preset: strong
-|       ├── Tunnel IPv6: no
 |       ├── Network interface: tun0
 |       ├── Run OpenVPN as: root
 |       └── Verbosity level: 1

internal/configuration/settings/vpn.go

@@ -20,7 +20,7 @@ type VPN struct {
 }
 
 // TODO v4 remove pointer for receiver (because of Surfshark).
-func (v *VPN) Validate(storage Storage) (err error) {
+func (v *VPN) Validate(storage Storage, ipv6Supported bool) (err error) {
 	// Validate Type
 	validVPNTypes := []string{vpn.OpenVPN, vpn.Wireguard}
 	if !helpers.IsOneOf(v.Type, validVPNTypes...) {
@@ -39,7 +39,7 @@ func (v *VPN) Validate(storage Storage) (err error) {
 			return fmt.Errorf("OpenVPN settings: %w", err)
 		}
 	} else {
-		err := v.Wireguard.validate(*v.Provider.Name)
+		err := v.Wireguard.validate(*v.Provider.Name, ipv6Supported)
 		if err != nil {
 			return fmt.Errorf("Wireguard settings: %w", err)
 		}

internal/configuration/settings/wireguard.go

@@ -27,17 +27,23 @@ type Wireguard struct {
 	// to create. It cannot be the empty string in the
 	// internal state.
 	Interface string
+	// Implementation is the Wireguard implementation to use.
+	// It can be "auto", "userspace" or "kernelspace".
+	// It defaults to "auto" and cannot be the empty string
+	// in the internal state.
+	Implementation string
 }
 
 var regexpInterfaceName = regexp.MustCompile(`^[a-zA-Z0-9_]+$`)
 
 // Validate validates Wireguard settings.
 // It should only be ran if the VPN type chosen is Wireguard.
-func (w Wireguard) validate(vpnProvider string) (err error) {
+func (w Wireguard) validate(vpnProvider string, ipv6Supported bool) (err error) {
 	if !helpers.IsOneOf(vpnProvider,
 		providers.Custom,
 		providers.Ivpn,
 		providers.Mullvad,
+		providers.Surfshark,
 		providers.Windscribe,
 	) {
 		// do not validate for VPN provider not supporting Wireguard
@@ -53,6 +59,12 @@ func (w Wireguard) validate(vpnProvider string) (err error) {
 		return fmt.Errorf("private key is not valid: %w", err)
 	}
 
+	if vpnProvider == providers.Airvpn {
+		if *w.PreSharedKey == "" {
+			return fmt.Errorf("%w", ErrWireguardPreSharedKeyNotSet)
+		}
+	}
+
 	// Validate PreSharedKey
 	if *w.PreSharedKey != "" { // Note: this is optional
 		_, err = wgtypes.ParseKey(*w.PreSharedKey)
@@ -70,6 +82,12 @@ func (w Wireguard) validate(vpnProvider string) (err error) {
 			return fmt.Errorf("%w: for address at index %d: %s",
 				ErrWireguardInterfaceAddressNotSet, i, ipNet.String())
 		}
+
+		ipv6Net := ipNet.IP.To4() == nil
+		if ipv6Net && !ipv6Supported {
+			return fmt.Errorf("%w: address %s",
+				ErrWireguardInterfaceAddressIPv6, ipNet)
+		}
 	}
 
 	// Validate interface
@@ -78,15 +96,22 @@ func (w Wireguard) validate(vpnProvider string) (err error) {
 			ErrWireguardInterfaceNotValid, w.Interface, regexpInterfaceName)
 	}
 
+	validImplementations := []string{"auto", "userspace", "kernelspace"}
+	if !helpers.IsOneOf(w.Implementation, validImplementations...) {
+		return fmt.Errorf("%w: %s must be one of %s", ErrWireguardImplementationNotValid,
+			w.Implementation, helpers.ChoicesOrString(validImplementations))
+	}
+
 	return nil
 }
 
 func (w *Wireguard) copy() (copied Wireguard) {
 	return Wireguard{
-		PrivateKey:   helpers.CopyStringPtr(w.PrivateKey),
-		PreSharedKey: helpers.CopyStringPtr(w.PreSharedKey),
-		Addresses:    helpers.CopyIPNetSlice(w.Addresses),
-		Interface:    w.Interface,
+		PrivateKey:     helpers.CopyStringPtr(w.PrivateKey),
+		PreSharedKey:   helpers.CopyStringPtr(w.PreSharedKey),
+		Addresses:      helpers.CopyIPNetSlice(w.Addresses),
+		Interface:      w.Interface,
+		Implementation: w.Implementation,
 	}
 }
 
@@ -95,6 +120,7 @@ func (w *Wireguard) mergeWith(other Wireguard) {
 	w.PreSharedKey = helpers.MergeWithStringPtr(w.PreSharedKey, other.PreSharedKey)
 	w.Addresses = helpers.MergeIPNetsSlices(w.Addresses, other.Addresses)
 	w.Interface = helpers.MergeWithString(w.Interface, other.Interface)
+	w.Implementation = helpers.MergeWithString(w.Implementation, other.Implementation)
 }
 
 func (w *Wireguard) overrideWith(other Wireguard) {
@@ -102,12 +128,14 @@ func (w *Wireguard) overrideWith(other Wireguard) {
 	w.PreSharedKey = helpers.OverrideWithStringPtr(w.PreSharedKey, other.PreSharedKey)
 	w.Addresses = helpers.OverrideWithIPNetsSlice(w.Addresses, other.Addresses)
 	w.Interface = helpers.OverrideWithString(w.Interface, other.Interface)
+	w.Implementation = helpers.OverrideWithString(w.Implementation, other.Implementation)
 }
 
 func (w *Wireguard) setDefaults() {
 	w.PrivateKey = helpers.DefaultStringPtr(w.PrivateKey, "")
 	w.PreSharedKey = helpers.DefaultStringPtr(w.PreSharedKey, "")
 	w.Interface = helpers.DefaultString(w.Interface, "wg0")
+	w.Implementation = helpers.DefaultString(w.Implementation, "auto")
 }
 
 func (w Wireguard) String() string {
@@ -134,5 +162,9 @@ func (w Wireguard) toLinesNode() (node *gotree.Node) {
 
 	node.Appendf("Network interface: %s", w.Interface)
 
+	if w.Implementation != "auto" {
+		node.Appendf("Implementation: %s", w.Implementation)
+	}
+
 	return node
 }

internal/configuration/settings/wireguardselection.go

@@ -19,7 +19,7 @@ type WireguardSelection struct {
 	// in the internal state.
 	EndpointIP net.IP
 	// EndpointPort is a the server port to use for the VPN server.
-	// It is optional for VPN providers IVPN, Mullvad
+	// It is optional for VPN providers IVPN, Mullvad, Surfshark
 	// and Windscribe, and compulsory for the others.
 	// When optional, it can be set to 0 to indicate not use
 	// a custom endpoint port. It cannot be nil in the internal
@@ -36,7 +36,9 @@ type WireguardSelection struct {
 func (w WireguardSelection) validate(vpnProvider string) (err error) {
 	// Validate EndpointIP
 	switch vpnProvider {
-	case providers.Ivpn, providers.Mullvad, providers.Windscribe: // endpoint IP addresses are baked in
+	case providers.Airvpn, providers.Ivpn, providers.Mullvad,
+		providers.Surfshark, providers.Windscribe:
+		// endpoint IP addresses are baked in
 	case providers.Custom:
 		if len(w.EndpointIP) == 0 {
 			return ErrWireguardEndpointIPNotSet
@@ -51,7 +53,12 @@ func (w WireguardSelection) validate(vpnProvider string) (err error) {
 		if *w.EndpointPort == 0 {
 			return ErrWireguardEndpointPortNotSet
 		}
-	case providers.Ivpn, providers.Mullvad, providers.Windscribe:
+	// EndpointPort cannot be set
+	case providers.Surfshark:
+		if *w.EndpointPort != 0 {
+			return ErrWireguardEndpointPortSet
+		}
+	case providers.Airvpn, providers.Ivpn, providers.Mullvad, providers.Windscribe:
 		// EndpointPort is optional and can be 0
 		if *w.EndpointPort == 0 {
 			break // no custom endpoint port set
@@ -61,6 +68,8 @@ func (w WireguardSelection) validate(vpnProvider string) (err error) {
 		}
 		var allowed []uint16
 		switch vpnProvider {
+		case providers.Airvpn:
+			allowed = []uint16{1637, 47107}
 		case providers.Ivpn:
 			allowed = []uint16{2049, 2050, 53, 30587, 41893, 48574, 58237}
 		case providers.Windscribe:
@@ -78,7 +87,9 @@ func (w WireguardSelection) validate(vpnProvider string) (err error) {
 
 	// Validate PublicKey
 	switch vpnProvider {
-	case providers.Ivpn, providers.Mullvad, providers.Windscribe: // public keys are baked in
+	case providers.Ivpn, providers.Mullvad,
+		providers.Surfshark, providers.Windscribe:
+		// public keys are baked in
 	case providers.Custom:
 		if w.PublicKey == "" {
 			return ErrWireguardPublicKeyNotSet

internal/configuration/sources/env/dns.go

@@ -7,8 +7,8 @@ import (
 	"github.com/qdm12/gluetun/internal/configuration/settings"
 )
 
-func (r *Reader) readDNS() (dns settings.DNS, err error) {
-	dns.ServerAddress, err = r.readDNSServerAddress()
+func (s *Source) readDNS() (dns settings.DNS, err error) {
+	dns.ServerAddress, err = s.readDNSServerAddress()
 	if err != nil {
 		return dns, err
 	}
@@ -18,7 +18,7 @@ func (r *Reader) readDNS() (dns settings.DNS, err error) {
 		return dns, fmt.Errorf("environment variable DNS_KEEP_NAMESERVER: %w", err)
 	}
 
-	dns.DoT, err = r.readDoT()
+	dns.DoT, err = s.readDoT()
 	if err != nil {
 		return dns, fmt.Errorf("DoT settings: %w", err)
 	}
@@ -26,22 +26,22 @@ func (r *Reader) readDNS() (dns settings.DNS, err error) {
 	return dns, nil
 }
 
-func (r *Reader) readDNSServerAddress() (address net.IP, err error) {
-	key, s := r.getEnvWithRetro("DNS_ADDRESS", "DNS_PLAINTEXT_ADDRESS")
-	if s == "" {
+func (s *Source) readDNSServerAddress() (address net.IP, err error) {
+	key, value := s.getEnvWithRetro("DNS_ADDRESS", "DNS_PLAINTEXT_ADDRESS")
+	if value == "" {
 		return nil, nil
 	}
 
-	address = net.ParseIP(s)
+	address = net.ParseIP(value)
 	if address == nil {
-		return nil, fmt.Errorf("environment variable %s: %w: %s", key, ErrIPAddressParse, s)
+		return nil, fmt.Errorf("environment variable %s: %w: %s", key, ErrIPAddressParse, value)
 	}
 
 	// TODO remove in v4
 	if !address.Equal(net.IPv4(127, 0, 0, 1)) { //nolint:gomnd
-		r.warner.Warn(key + " is set to " + s +
+		s.warner.Warn(key + " is set to " + value +
 			" so the DNS over TLS (DoT) server will not be used." +
-			" The default value changed to 127.0.0.1 so it uses the internal DoT server." +
+			" The default value changed to 127.0.0.1 so it uses the internal DoT serves." +
 			" If the DoT server fails to start, the IPv4 address of the first plaintext DNS server" +
 			" corresponding to the first DoT provider chosen is used.")
 	}

internal/configuration/sources/env/dnsblacklist.go

@@ -9,13 +9,13 @@ import (
 	"inet.af/netaddr"
 )
 
-func (r *Reader) readDNSBlacklist() (blacklist settings.DNSBlacklist, err error) {
+func (s *Source) readDNSBlacklist() (blacklist settings.DNSBlacklist, err error) {
 	blacklist.BlockMalicious, err = envToBoolPtr("BLOCK_MALICIOUS")
 	if err != nil {
 		return blacklist, fmt.Errorf("environment variable BLOCK_MALICIOUS: %w", err)
 	}
 
-	blacklist.BlockSurveillance, err = r.readBlockSurveillance()
+	blacklist.BlockSurveillance, err = s.readBlockSurveillance()
 	if err != nil {
 		return blacklist, err
 	}
@@ -36,8 +36,8 @@ func (r *Reader) readDNSBlacklist() (blacklist settings.DNSBlacklist, err error)
 	return blacklist, nil
 }
 
-func (r *Reader) readBlockSurveillance() (blocked *bool, err error) {
-	key, value := r.getEnvWithRetro("BLOCK_SURVEILLANCE", "BLOCK_NSA")
+func (s *Source) readBlockSurveillance() (blocked *bool, err error) {
+	key, value := s.getEnvWithRetro("BLOCK_SURVEILLANCE", "BLOCK_NSA")
 	if value == "" {
 		return nil, nil //nolint:nilnil
 	}

internal/configuration/sources/env/dot.go

@@ -6,7 +6,7 @@ import (
 	"github.com/qdm12/gluetun/internal/configuration/settings"
 )
 
-func (r *Reader) readDoT() (dot settings.DoT, err error) {
+func (s *Source) readDoT() (dot settings.DoT, err error) {
 	dot.Enabled, err = envToBoolPtr("DOT")
 	if err != nil {
 		return dot, fmt.Errorf("environment variable DOT: %w", err)
@@ -22,7 +22,7 @@ func (r *Reader) readDoT() (dot settings.DoT, err error) {
 		return dot, err
 	}
 
-	dot.Blacklist, err = r.readDNSBlacklist()
+	dot.Blacklist, err = s.readDNSBlacklist()
 	if err != nil {
 		return dot, err
 	}

internal/configuration/sources/env/firewall.go

@@ -9,7 +9,7 @@ import (
 	"github.com/qdm12/gluetun/internal/configuration/settings"
 )
 
-func (r *Reader) readFirewall() (firewall settings.Firewall, err error) {
+func (s *Source) readFirewall() (firewall settings.Firewall, err error) {
 	vpnInputPortStrings := envToCSV("FIREWALL_VPN_INPUT_PORTS")
 	firewall.VPNInputPorts, err = stringsToPorts(vpnInputPortStrings)
 	if err != nil {
@@ -22,7 +22,7 @@ func (r *Reader) readFirewall() (firewall settings.Firewall, err error) {
 		return firewall, fmt.Errorf("environment variable FIREWALL_INPUT_PORTS: %w", err)
 	}
 
-	outboundSubnetsKey, _ := r.getEnvWithRetro("FIREWALL_OUTBOUND_SUBNETS", "EXTRA_SUBNETS")
+	outboundSubnetsKey, _ := s.getEnvWithRetro("FIREWALL_OUTBOUND_SUBNETS", "EXTRA_SUBNETS")
 	outboundSubnetStrings := envToCSV(outboundSubnetsKey)
 	firewall.OutboundSubnets, err = stringsToIPNets(outboundSubnetStrings)
 	if err != nil {
@@ -73,7 +73,7 @@ func stringsToIPNets(ss []string) (ipNets []net.IPNet, err error) {
 	for i, s := range ss {
 		ip, ipNet, err := net.ParseCIDR(s)
 		if err != nil {
-			return nil, fmt.Errorf("cannot parse IP network %q: %w", s, err)
+			return nil, fmt.Errorf("parsing IP network %q: %w", s, err)
 		}
 		ipNet.IP = ip
 		ipNets[i] = *ipNet

internal/configuration/sources/env/health.go

@@ -7,18 +7,18 @@ import (
 	"github.com/qdm12/gluetun/internal/configuration/settings"
 )
 
-func (r *Reader) ReadHealth() (health settings.Health, err error) {
+func (s *Source) ReadHealth() (health settings.Health, err error) {
 	health.ServerAddress = getCleanedEnv("HEALTH_SERVER_ADDRESS")
-	_, health.TargetAddress = r.getEnvWithRetro("HEALTH_TARGET_ADDRESS", "HEALTH_ADDRESS_TO_PING")
+	_, health.TargetAddress = s.getEnvWithRetro("HEALTH_TARGET_ADDRESS", "HEALTH_ADDRESS_TO_PING")
 
-	health.VPN.Initial, err = r.readDurationWithRetro(
+	health.VPN.Initial, err = s.readDurationWithRetro(
 		"HEALTH_VPN_DURATION_INITIAL",
 		"HEALTH_OPENVPN_DURATION_INITIAL")
 	if err != nil {
 		return health, err
 	}
 
-	health.VPN.Addition, err = r.readDurationWithRetro(
+	health.VPN.Addition, err = s.readDurationWithRetro(
 		"HEALTH_VPN_DURATION_ADDITION",
 		"HEALTH_OPENVPN_DURATION_ADDITION")
 	if err != nil {
@@ -28,14 +28,14 @@ func (r *Reader) ReadHealth() (health settings.Health, err error) {
 	return health, nil
 }
 
-func (r *Reader) readDurationWithRetro(envKey, retroEnvKey string) (d *time.Duration, err error) {
-	envKey, s := r.getEnvWithRetro(envKey, retroEnvKey)
-	if s == "" {
+func (s *Source) readDurationWithRetro(envKey, retroEnvKey string) (d *time.Duration, err error) {
+	envKey, value := s.getEnvWithRetro(envKey, retroEnvKey)
+	if value == "" {
 		return nil, nil //nolint:nilnil
 	}
 
 	d = new(time.Duration)
-	*d, err = time.ParseDuration(s)
+	*d, err = time.ParseDuration(value)
 	if err != nil {
 		return nil, fmt.Errorf("environment variable %s: %w", envKey, err)
 	}

internal/configuration/sources/env/helpers.go

@@ -137,7 +137,7 @@ func unsetEnvKeys(envKeys []string, err error) (newErr error) {
 	for _, envKey := range envKeys {
 		unsetErr := os.Unsetenv(envKey)
 		if unsetErr != nil && newErr == nil {
-			newErr = fmt.Errorf("cannot unset environment variable %s: %w", envKey, unsetErr)
+			newErr = fmt.Errorf("unsetting environment variable %s: %w", envKey, unsetErr)
 		}
 	}
 	return newErr

internal/configuration/sources/env/httproxy.go

@@ -7,12 +7,12 @@ import (
 	"github.com/qdm12/govalid/binary"
 )
 
-func (r *Reader) readHTTPProxy() (httpProxy settings.HTTPProxy, err error) {
-	httpProxy.User = r.readHTTProxyUser()
-	httpProxy.Password = r.readHTTProxyPassword()
-	httpProxy.ListeningAddress = r.readHTTProxyListeningAddress()
+func (s *Source) readHTTPProxy() (httpProxy settings.HTTPProxy, err error) {
+	httpProxy.User = s.readHTTProxyUser()
+	httpProxy.Password = s.readHTTProxyPassword()
+	httpProxy.ListeningAddress = s.readHTTProxyListeningAddress()
 
-	httpProxy.Enabled, err = r.readHTTProxyEnabled()
+	httpProxy.Enabled, err = s.readHTTProxyEnabled()
 	if err != nil {
 		return httpProxy, err
 	}
@@ -22,7 +22,7 @@ func (r *Reader) readHTTPProxy() (httpProxy settings.HTTPProxy, err error) {
 		return httpProxy, fmt.Errorf("environment variable HTTPPROXY_STEALTH: %w", err)
 	}
 
-	httpProxy.Log, err = r.readHTTProxyLog()
+	httpProxy.Log, err = s.readHTTProxyLog()
 	if err != nil {
 		return httpProxy, err
 	}
@@ -30,38 +30,38 @@ func (r *Reader) readHTTPProxy() (httpProxy settings.HTTPProxy, err error) {
 	return httpProxy, nil
 }
 
-func (r *Reader) readHTTProxyUser() (user *string) {
-	_, s := r.getEnvWithRetro("HTTPPROXY_USER", "PROXY_USER", "TINYPROXY_USER")
-	if s != "" {
-		return &s
+func (s *Source) readHTTProxyUser() (user *string) {
+	_, value := s.getEnvWithRetro("HTTPPROXY_USER", "PROXY_USER", "TINYPROXY_USER")
+	if value != "" {
+		return &value
 	}
 	return nil
 }
 
-func (r *Reader) readHTTProxyPassword() (user *string) {
-	_, s := r.getEnvWithRetro("HTTPPROXY_PASSWORD", "PROXY_PASSWORD", "TINYPROXY_PASSWORD")
-	if s != "" {
-		return &s
+func (s *Source) readHTTProxyPassword() (user *string) {
+	_, value := s.getEnvWithRetro("HTTPPROXY_PASSWORD", "PROXY_PASSWORD", "TINYPROXY_PASSWORD")
+	if value != "" {
+		return &value
 	}
 	return nil
 }
 
-func (r *Reader) readHTTProxyListeningAddress() (listeningAddress string) {
-	key, value := r.getEnvWithRetro("HTTPPROXY_LISTENING_ADDRESS", "PROXY_PORT", "TINYPROXY_PORT", "HTTPPROXY_PORT")
+func (s *Source) readHTTProxyListeningAddress() (listeningAddress string) {
+	key, value := s.getEnvWithRetro("HTTPPROXY_LISTENING_ADDRESS", "PROXY_PORT", "TINYPROXY_PORT", "HTTPPROXY_PORT")
 	if key == "HTTPPROXY_LISTENING_ADDRESS" {
 		return value
 	}
 	return ":" + value
 }
 
-func (r *Reader) readHTTProxyEnabled() (enabled *bool, err error) {
-	key, s := r.getEnvWithRetro("HTTPPROXY", "PROXY", "TINYPROXY")
-	if s == "" {
+func (s *Source) readHTTProxyEnabled() (enabled *bool, err error) {
+	key, value := s.getEnvWithRetro("HTTPPROXY", "PROXY", "TINYPROXY")
+	if value == "" {
 		return nil, nil //nolint:nilnil
 	}
 
 	enabled = new(bool)
-	*enabled, err = binary.Validate(s)
+	*enabled, err = binary.Validate(value)
 	if err != nil {
 		return nil, fmt.Errorf("environment variable %s: %w", key, err)
 	}
@@ -69,9 +69,9 @@ func (r *Reader) readHTTProxyEnabled() (enabled *bool, err error) {
 	return enabled, nil
 }
 
-func (r *Reader) readHTTProxyLog() (enabled *bool, err error) {
-	key, s := r.getEnvWithRetro("HTTPPROXY_LOG", "PROXY_LOG_LEVEL", "TINYPROXY_LOG")
-	if s == "" {
+func (s *Source) readHTTProxyLog() (enabled *bool, err error) {
+	key, value := s.getEnvWithRetro("HTTPPROXY_LOG", "PROXY_LOG_LEVEL", "TINYPROXY_LOG")
+	if value == "" {
 		return nil, nil //nolint:nilnil
 	}
 
@@ -82,7 +82,7 @@ func (r *Reader) readHTTProxyLog() (enabled *bool, err error) {
 	}
 
 	enabled = new(bool)
-	*enabled, err = binary.Validate(s, binaryOptions...)
+	*enabled, err = binary.Validate(value, binaryOptions...)
 	if err != nil {
 		return nil, fmt.Errorf("environment variable %s: %w", key, err)
 	}

internal/configuration/sources/env/openvpn.go

@@ -8,7 +8,7 @@ import (
 	"github.com/qdm12/govalid/binary"
 )
 
-func (r *Reader) readOpenVPN() (
+func (s *Source) readOpenVPN() (
 	openVPN settings.OpenVPN, err error) {
 	defer func() {
 		err = unsetEnvKeys([]string{"OPENVPN_KEY", "OPENVPN_CERT",
@@ -16,14 +16,14 @@ func (r *Reader) readOpenVPN() (
 	}()
 
 	openVPN.Version = getCleanedEnv("OPENVPN_VERSION")
-	openVPN.User = r.readOpenVPNUser()
-	openVPN.Password = r.readOpenVPNPassword()
+	openVPN.User = s.readOpenVPNUser()
+	openVPN.Password = s.readOpenVPNPassword()
 	confFile := getCleanedEnv("OPENVPN_CUSTOM_CONFIG")
 	if confFile != "" {
 		openVPN.ConfFile = &confFile
 	}
 
-	ciphersKey, _ := r.getEnvWithRetro("OPENVPN_CIPHERS", "OPENVPN_CIPHER")
+	ciphersKey, _ := s.getEnvWithRetro("OPENVPN_CIPHERS", "OPENVPN_CIPHER")
 	openVPN.Ciphers = envToCSV(ciphersKey)
 
 	auth := getCleanedEnv("OPENVPN_AUTH")
@@ -35,23 +35,18 @@ func (r *Reader) readOpenVPN() (
 	openVPN.Key = envToStringPtr("OPENVPN_KEY")
 	openVPN.EncryptedKey = envToStringPtr("OPENVPN_ENCRYPTED_KEY")
 
-	openVPN.KeyPassphrase = r.readOpenVPNKeyPassphrase()
+	openVPN.KeyPassphrase = s.readOpenVPNKeyPassphrase()
 
-	openVPN.PIAEncPreset = r.readPIAEncryptionPreset()
-
-	openVPN.IPv6, err = envToBoolPtr("OPENVPN_IPV6")
-	if err != nil {
-		return openVPN, fmt.Errorf("environment variable OPENVPN_IPV6: %w", err)
-	}
+	openVPN.PIAEncPreset = s.readPIAEncryptionPreset()
 
 	openVPN.MSSFix, err = envToUint16Ptr("OPENVPN_MSSFIX")
 	if err != nil {
 		return openVPN, fmt.Errorf("environment variable OPENVPN_MSSFIX: %w", err)
 	}
 
-	_, openVPN.Interface = r.getEnvWithRetro("VPN_INTERFACE", "OPENVPN_INTERFACE")
+	_, openVPN.Interface = s.getEnvWithRetro("VPN_INTERFACE", "OPENVPN_INTERFACE")
 
-	openVPN.ProcessUser, err = r.readOpenVPNProcessUser()
+	openVPN.ProcessUser, err = s.readOpenVPNProcessUser()
 	if err != nil {
 		return openVPN, err
 	}
@@ -69,9 +64,9 @@ func (r *Reader) readOpenVPN() (
 	return openVPN, nil
 }
 
-func (r *Reader) readOpenVPNUser() (user *string) {
+func (s *Source) readOpenVPNUser() (user *string) {
 	user = new(string)
-	_, *user = r.getEnvWithRetro("OPENVPN_USER", "USER")
+	_, *user = s.getEnvWithRetro("OPENVPN_USER", "USER")
 	if *user == "" {
 		return nil
 	}
@@ -81,9 +76,9 @@ func (r *Reader) readOpenVPNUser() (user *string) {
 	return user
 }
 
-func (r *Reader) readOpenVPNPassword() (password *string) {
+func (s *Source) readOpenVPNPassword() (password *string) {
 	password = new(string)
-	_, *password = r.getEnvWithRetro("OPENVPN_PASSWORD", "PASSWORD")
+	_, *password = s.getEnvWithRetro("OPENVPN_PASSWORD", "PASSWORD")
 	if *password == "" {
 		return nil
 	}
@@ -91,7 +86,7 @@ func (r *Reader) readOpenVPNPassword() (password *string) {
 	return password
 }
 
-func (r *Reader) readOpenVPNKeyPassphrase() (passphrase *string) {
+func (s *Source) readOpenVPNKeyPassphrase() (passphrase *string) {
 	passphrase = new(string)
 	*passphrase = getCleanedEnv("OPENVPN_KEY_PASSPHRASE")
 	if *passphrase == "" {
@@ -100,8 +95,8 @@ func (r *Reader) readOpenVPNKeyPassphrase() (passphrase *string) {
 	return passphrase
 }
 
-func (r *Reader) readPIAEncryptionPreset() (presetPtr *string) {
-	_, preset := r.getEnvWithRetro(
+func (s *Source) readPIAEncryptionPreset() (presetPtr *string) {
+	_, preset := s.getEnvWithRetro(
 		"PRIVATE_INTERNET_ACCESS_OPENVPN_ENCRYPTION_PRESET",
 		"PIA_ENCRYPTION", "ENCRYPTION")
 	if preset != "" {
@@ -110,8 +105,8 @@ func (r *Reader) readPIAEncryptionPreset() (presetPtr *string) {
 	return nil
 }
 
-func (r *Reader) readOpenVPNProcessUser() (processUser string, err error) {
-	key, value := r.getEnvWithRetro("OPENVPN_PROCESS_USER", "OPENVPN_ROOT")
+func (s *Source) readOpenVPNProcessUser() (processUser string, err error) {
+	key, value := s.getEnvWithRetro("OPENVPN_PROCESS_USER", "OPENVPN_ROOT")
 	if key == "OPENVPN_PROCESS_USER" {
 		return value, nil
 	}

internal/configuration/sources/env/openvpnselection.go

@@ -10,32 +10,32 @@ import (
 	"github.com/qdm12/govalid/port"
 )
 
-func (r *Reader) readOpenVPNSelection() (
+func (s *Source) readOpenVPNSelection() (
 	selection settings.OpenVPNSelection, err error) {
 	confFile := getCleanedEnv("OPENVPN_CUSTOM_CONFIG")
 	if confFile != "" {
 		selection.ConfFile = &confFile
 	}
 
-	selection.TCP, err = r.readOpenVPNProtocol()
+	selection.TCP, err = s.readOpenVPNProtocol()
 	if err != nil {
 		return selection, err
 	}
 
-	selection.CustomPort, err = r.readOpenVPNCustomPort()
+	selection.CustomPort, err = s.readOpenVPNCustomPort()
 	if err != nil {
 		return selection, err
 	}
 
-	selection.PIAEncPreset = r.readPIAEncryptionPreset()
+	selection.PIAEncPreset = s.readPIAEncryptionPreset()
 
 	return selection, nil
 }
 
 var ErrOpenVPNProtocolNotValid = errors.New("OpenVPN protocol is not valid")
 
-func (r *Reader) readOpenVPNProtocol() (tcp *bool, err error) {
-	envKey, protocol := r.getEnvWithRetro("OPENVPN_PROTOCOL", "PROTOCOL")
+func (s *Source) readOpenVPNProtocol() (tcp *bool, err error) {
+	envKey, protocol := s.getEnvWithRetro("OPENVPN_PROTOCOL", "PROTOCOL")
 
 	switch strings.ToLower(protocol) {
 	case "":
@@ -50,14 +50,14 @@ func (r *Reader) readOpenVPNProtocol() (tcp *bool, err error) {
 	}
 }
 
-func (r *Reader) readOpenVPNCustomPort() (customPort *uint16, err error) {
-	key, s := r.getEnvWithRetro("VPN_ENDPOINT_PORT", "PORT", "OPENVPN_PORT")
-	if s == "" {
+func (s *Source) readOpenVPNCustomPort() (customPort *uint16, err error) {
+	key, value := s.getEnvWithRetro("VPN_ENDPOINT_PORT", "PORT", "OPENVPN_PORT")
+	if value == "" {
 		return nil, nil //nolint:nilnil
 	}
 
 	customPort = new(uint16)
-	*customPort, err = port.Validate(s)
+	*customPort, err = port.Validate(value)
 	if err != nil {
 		return nil, fmt.Errorf("environment variable %s: %w", key, err)
 	}

internal/configuration/sources/env/portforward.go

@@ -6,9 +6,9 @@ import (
 	"github.com/qdm12/gluetun/internal/configuration/settings"
 )
 
-func (r *Reader) readPortForward() (
+func (s *Source) readPortForward() (
 	portForwarding settings.PortForwarding, err error) {
-	key, _ := r.getEnvWithRetro(
+	key, _ := s.getEnvWithRetro(
 		"PRIVATE_INTERNET_ACCESS_VPN_PORT_FORWARDING",
 		"PORT_FORWARDING")
 	portForwarding.Enabled, err = envToBoolPtr(key)
@@ -16,7 +16,7 @@ func (r *Reader) readPortForward() (
 		return portForwarding, fmt.Errorf("environment variable %s: %w", key, err)
 	}
 
-	_, value := r.getEnvWithRetro(
+	_, value := s.getEnvWithRetro(
 		"PRIVATE_INTERNET_ACCESS_VPN_PORT_FORWARDING_STATUS_FILE",
 		"PORT_FORWARDING_STATUS_FILE")
 	if value != "" {

internal/configuration/sources/env/provider.go

@@ -9,19 +9,19 @@ import (
 	"github.com/qdm12/gluetun/internal/constants/vpn"
 )
 
-func (r *Reader) readProvider(vpnType string) (provider settings.Provider, err error) {
-	provider.Name = r.readVPNServiceProvider(vpnType)
+func (s *Source) readProvider(vpnType string) (provider settings.Provider, err error) {
+	provider.Name = s.readVPNServiceProvider(vpnType)
 	var providerName string
 	if provider.Name != nil {
 		providerName = *provider.Name
 	}
 
-	provider.ServerSelection, err = r.readServerSelection(providerName, vpnType)
+	provider.ServerSelection, err = s.readServerSelection(providerName, vpnType)
 	if err != nil {
 		return provider, fmt.Errorf("server selection: %w", err)
 	}
 
-	provider.PortForwarding, err = r.readPortForward()
+	provider.PortForwarding, err = s.readPortForward()
 	if err != nil {
 		return provider, fmt.Errorf("port forwarding: %w", err)
 	}
@@ -29,17 +29,20 @@ func (r *Reader) readProvider(vpnType string) (provider settings.Provider, err e
 	return provider, nil
 }
 
-func (r *Reader) readVPNServiceProvider(vpnType string) (vpnProviderPtr *string) {
-	_, s := r.getEnvWithRetro("VPN_SERVICE_PROVIDER", "VPNSP")
-	s = strings.ToLower(s)
-	switch {
-	case vpnType != vpn.Wireguard &&
-		getCleanedEnv("OPENVPN_CUSTOM_CONFIG") != "": // retro compatibility
-		return stringPtr(providers.Custom)
-	case s == "":
+func (s *Source) readVPNServiceProvider(vpnType string) (vpnProviderPtr *string) {
+	_, value := s.getEnvWithRetro("VPN_SERVICE_PROVIDER", "VPNSP")
+	if value == "" {
+		if vpnType != vpn.Wireguard && getCleanedEnv("OPENVPN_CUSTOM_CONFIG") != "" {
+			// retro compatibility
+			return stringPtr(providers.Custom)
+		}
 		return nil
-	case s == "pia": // retro compatibility
+	}
+
+	value = strings.ToLower(value)
+	if value == "pia" { // retro compatibility
 		return stringPtr(providers.PrivateInternetAccess)
 	}
-	return stringPtr(s)
+
+	return stringPtr(value)
 }

internal/configuration/sources/env/publicip.go

@@ -7,13 +7,13 @@ import (
 	"github.com/qdm12/gluetun/internal/configuration/settings"
 )
 
-func (r *Reader) readPublicIP() (publicIP settings.PublicIP, err error) {
+func (s *Source) readPublicIP() (publicIP settings.PublicIP, err error) {
 	publicIP.Period, err = readPublicIPPeriod()
 	if err != nil {
 		return publicIP, err
 	}
 
-	publicIP.IPFilepath = r.readPublicIPFilepath()
+	publicIP.IPFilepath = s.readPublicIPFilepath()
 
 	return publicIP, nil
 }
@@ -33,10 +33,10 @@ func readPublicIPPeriod() (period *time.Duration, err error) {
 	return period, nil
 }
 
-func (r *Reader) readPublicIPFilepath() (filepath *string) {
-	_, s := r.getEnvWithRetro("PUBLICIP_FILE", "IP_STATUS_FILE")
-	if s != "" {
-		return &s
+func (s *Source) readPublicIPFilepath() (filepath *string) {
+	_, value := s.getEnvWithRetro("PUBLICIP_FILE", "IP_STATUS_FILE")
+	if value != "" {
+		return &value
 	}
 	return nil
 }

internal/configuration/sources/env/reader.go

@@ -2,12 +2,9 @@ package env
 
 import (
 	"github.com/qdm12/gluetun/internal/configuration/settings"
-	"github.com/qdm12/gluetun/internal/configuration/sources"
 )
 
-var _ sources.Source = (*Reader)(nil)
-
-type Reader struct {
+type Source struct {
 	warner Warner
 }
 
@@ -15,36 +12,36 @@ type Warner interface {
 	Warn(s string)
 }
 
-func New(warner Warner) *Reader {
-	return &Reader{
+func New(warner Warner) *Source {
+	return &Source{
 		warner: warner,
 	}
 }
 
-func (r *Reader) String() string { return "environment variables" }
+func (s *Source) String() string { return "environment variables" }
 
-func (r *Reader) Read() (settings settings.Settings, err error) {
-	settings.VPN, err = r.readVPN()
+func (s *Source) Read() (settings settings.Settings, err error) {
+	settings.VPN, err = s.readVPN()
 	if err != nil {
 		return settings, err
 	}
 
-	settings.Firewall, err = r.readFirewall()
+	settings.Firewall, err = s.readFirewall()
 	if err != nil {
 		return settings, err
 	}
 
-	settings.System, err = r.readSystem()
+	settings.System, err = s.readSystem()
 	if err != nil {
 		return settings, err
 	}
 
-	settings.Health, err = r.ReadHealth()
+	settings.Health, err = s.ReadHealth()
 	if err != nil {
 		return settings, err
 	}
 
-	settings.HTTPProxy, err = r.readHTTPProxy()
+	settings.HTTPProxy, err = s.readHTTPProxy()
 	if err != nil {
 		return settings, err
 	}
@@ -54,7 +51,7 @@ func (r *Reader) Read() (settings settings.Settings, err error) {
 		return settings, err
 	}
 
-	settings.PublicIP, err = r.readPublicIP()
+	settings.PublicIP, err = s.readPublicIP()
 	if err != nil {
 		return settings, err
 	}
@@ -69,17 +66,17 @@ func (r *Reader) Read() (settings settings.Settings, err error) {
 		return settings, err
 	}
 
-	settings.Shadowsocks, err = r.readShadowsocks()
+	settings.Shadowsocks, err = s.readShadowsocks()
 	if err != nil {
 		return settings, err
 	}
 
-	settings.DNS, err = r.readDNS()
+	settings.DNS, err = s.readDNS()
 	if err != nil {
 		return settings, err
 	}
 
-	settings.ControlServer, err = r.readControlServer()
+	settings.ControlServer, err = s.readControlServer()
 	if err != nil {
 		return settings, err
 	}
@@ -92,8 +89,8 @@ func (r *Reader) Read() (settings settings.Settings, err error) {
 	return settings, nil
 }
 
-func (r *Reader) onRetroActive(oldKey, newKey string) {
-	r.warner.Warn(
+func (s *Source) onRetroActive(oldKey, newKey string) {
+	s.warner.Warn(
 		"You are using the old environment variable " + oldKey +
 			", please consider changing it to " + newKey)
 }
@@ -104,14 +101,14 @@ func (r *Reader) onRetroActive(oldKey, newKey string) {
 // and end on returning the value corresponding to the currentKey.
 // Note retroKeys should be in order from oldest to most
 // recent retro-compatibility key.
-func (r *Reader) getEnvWithRetro(currentKey string,
+func (s *Source) getEnvWithRetro(currentKey string,
 	retroKeys ...string) (key, value string) {
 	// We check retro-compatibility keys first since
 	// the current key might be set in the Dockerfile.
 	for _, key = range retroKeys {
 		value = getCleanedEnv(key)
 		if value != "" {
-			r.onRetroActive(key, currentKey)
+			s.onRetroActive(key, currentKey)
 			return key, value
 		}
 	}

internal/configuration/sources/env/server.go

@@ -7,13 +7,13 @@ import (
 	"github.com/qdm12/govalid/binary"
 )
 
-func (r *Reader) readControlServer() (controlServer settings.ControlServer, err error) {
+func (s *Source) readControlServer() (controlServer settings.ControlServer, err error) {
 	controlServer.Log, err = readControlServerLog()
 	if err != nil {
 		return controlServer, err
 	}
 
-	controlServer.Address = r.readControlServerAddress()
+	controlServer.Address = s.readControlServerAddress()
 
 	return controlServer, nil
 }
@@ -32,17 +32,17 @@ func readControlServerLog() (enabled *bool, err error) {
 	return &log, nil
 }
 
-func (r *Reader) readControlServerAddress() (address *string) {
-	key, s := r.getEnvWithRetro("HTTP_CONTROL_SERVER_ADDRESS", "HTTP_CONTROL_SERVER_PORT")
-	if s == "" {
+func (s *Source) readControlServerAddress() (address *string) {
+	key, value := s.getEnvWithRetro("HTTP_CONTROL_SERVER_ADDRESS", "HTTP_CONTROL_SERVER_PORT")
+	if value == "" {
 		return nil
 	}
 
 	if key == "HTTP_CONTROL_SERVER_ADDRESS" {
-		return &s
+		return &value
 	}
 
 	address = new(string)
-	*address = ":" + s
+	*address = ":" + value
 	return address
 }

internal/configuration/sources/env/serverselection.go

@@ -15,44 +15,45 @@ var (
 	ErrServerNumberNotValid = errors.New("server number is not valid")
 )
 
-func (r *Reader) readServerSelection(vpnProvider, vpnType string) (
+func (s *Source) readServerSelection(vpnProvider, vpnType string) (
 	ss settings.ServerSelection, err error) {
 	ss.VPN = vpnType
 
-	ss.TargetIP, err = r.readOpenVPNTargetIP()
+	ss.TargetIP, err = s.readOpenVPNTargetIP()
 	if err != nil {
 		return ss, err
 	}
 
-	countriesKey, _ := r.getEnvWithRetro("SERVER_COUNTRIES", "COUNTRY")
+	countriesKey, _ := s.getEnvWithRetro("SERVER_COUNTRIES", "COUNTRY")
 	ss.Countries = envToCSV(countriesKey)
 	if vpnProvider == providers.Cyberghost && len(ss.Countries) == 0 {
 		// Retro-compatibility for Cyberghost using the REGION variable
 		ss.Countries = envToCSV("REGION")
 		if len(ss.Countries) > 0 {
-			r.onRetroActive("REGION", "SERVER_COUNTRIES")
+			s.onRetroActive("REGION", "SERVER_COUNTRIES")
 		}
 	}
 
-	regionsKey, _ := r.getEnvWithRetro("SERVER_REGIONS", "REGION")
+	regionsKey, _ := s.getEnvWithRetro("SERVER_REGIONS", "REGION")
 	ss.Regions = envToCSV(regionsKey)
 
-	citiesKey, _ := r.getEnvWithRetro("SERVER_CITIES", "CITY")
+	citiesKey, _ := s.getEnvWithRetro("SERVER_CITIES", "CITY")
 	ss.Cities = envToCSV(citiesKey)
 
 	ss.ISPs = envToCSV("ISP")
 
-	hostnamesKey, _ := r.getEnvWithRetro("SERVER_HOSTNAMES", "SERVER_HOSTNAME")
+	hostnamesKey, _ := s.getEnvWithRetro("SERVER_HOSTNAMES", "SERVER_HOSTNAME")
 	ss.Hostnames = envToCSV(hostnamesKey)
 
-	serverNamesKey, _ := r.getEnvWithRetro("SERVER_NAMES", "SERVER_NAME")
+	serverNamesKey, _ := s.getEnvWithRetro("SERVER_NAMES", "SERVER_NAME")
 	ss.Names = envToCSV(serverNamesKey)
 
 	if csv := getCleanedEnv("SERVER_NUMBER"); csv != "" {
 		numbersStrings := strings.Split(csv, ",")
 		numbers := make([]uint16, len(numbersStrings))
 		for i, numberString := range numbersStrings {
-			number, err := strconv.Atoi(numberString)
+			const base, bitSize = 10, 16
+			number, err := strconv.ParseInt(numberString, base, bitSize)
 			if err != nil {
 				return ss, fmt.Errorf("%w: %s",
 					ErrServerNumberNotValid, numberString)
@@ -66,7 +67,7 @@ func (r *Reader) readServerSelection(vpnProvider, vpnType string) (
 	}
 
 	// Mullvad only
-	ss.OwnedOnly, err = r.readOwnedOnly()
+	ss.OwnedOnly, err = s.readOwnedOnly()
 	if err != nil {
 		return ss, err
 	}
@@ -95,12 +96,12 @@ func (r *Reader) readServerSelection(vpnProvider, vpnType string) (
 		return ss, fmt.Errorf("environment variable STREAM_ONLY: %w", err)
 	}
 
-	ss.OpenVPN, err = r.readOpenVPNSelection()
+	ss.OpenVPN, err = s.readOpenVPNSelection()
 	if err != nil {
 		return ss, err
 	}
 
-	ss.Wireguard, err = r.readWireguardSelection()
+	ss.Wireguard, err = s.readWireguardSelection()
 	if err != nil {
 		return ss, err
 	}
@@ -112,23 +113,23 @@ var (
 	ErrInvalidIP = errors.New("invalid IP address")
 )
 
-func (r *Reader) readOpenVPNTargetIP() (ip net.IP, err error) {
-	envKey, s := r.getEnvWithRetro("VPN_ENDPOINT_IP", "OPENVPN_TARGET_IP")
-	if s == "" {
+func (s *Source) readOpenVPNTargetIP() (ip net.IP, err error) {
+	envKey, value := s.getEnvWithRetro("VPN_ENDPOINT_IP", "OPENVPN_TARGET_IP")
+	if value == "" {
 		return nil, nil
 	}
 
-	ip = net.ParseIP(s)
+	ip = net.ParseIP(value)
 	if ip == nil {
 		return nil, fmt.Errorf("environment variable %s: %w: %s",
-			envKey, ErrInvalidIP, s)
+			envKey, ErrInvalidIP, value)
 	}
 
 	return ip, nil
 }
 
-func (r *Reader) readOwnedOnly() (ownedOnly *bool, err error) {
-	envKey, _ := r.getEnvWithRetro("OWNED_ONLY", "OWNED")
+func (s *Source) readOwnedOnly() (ownedOnly *bool, err error) {
+	envKey, _ := s.getEnvWithRetro("OWNED_ONLY", "OWNED")
 	ownedOnly, err = envToBoolPtr(envKey)
 	if err != nil {
 		return nil, fmt.Errorf("environment variable %s: %w", envKey, err)

internal/configuration/sources/env/shadowsocks.go

@@ -7,25 +7,25 @@ import (
 	"github.com/qdm12/gluetun/internal/configuration/settings"
 )
 
-func (r *Reader) readShadowsocks() (shadowsocks settings.Shadowsocks, err error) {
+func (s *Source) readShadowsocks() (shadowsocks settings.Shadowsocks, err error) {
 	shadowsocks.Enabled, err = envToBoolPtr("SHADOWSOCKS")
 	if err != nil {
 		return shadowsocks, fmt.Errorf("environment variable SHADOWSOCKS: %w", err)
 	}
 
-	shadowsocks.Address = r.readShadowsocksAddress()
+	shadowsocks.Address = s.readShadowsocksAddress()
 	shadowsocks.LogAddresses, err = envToBoolPtr("SHADOWSOCKS_LOG")
 	if err != nil {
 		return shadowsocks, fmt.Errorf("environment variable SHADOWSOCKS_LOG: %w", err)
 	}
-	shadowsocks.CipherName = r.readShadowsocksCipher()
+	shadowsocks.CipherName = s.readShadowsocksCipher()
 	shadowsocks.Password = envToStringPtr("SHADOWSOCKS_PASSWORD")
 
 	return shadowsocks, nil
 }
 
-func (r *Reader) readShadowsocksAddress() (address string) {
-	key, value := r.getEnvWithRetro("SHADOWSOCKS_LISTENING_ADDRESS", "SHADOWSOCKS_PORT")
+func (s *Source) readShadowsocksAddress() (address string) {
+	key, value := s.getEnvWithRetro("SHADOWSOCKS_LISTENING_ADDRESS", "SHADOWSOCKS_PORT")
 	if value == "" {
 		return ""
 	}
@@ -38,7 +38,7 @@ func (r *Reader) readShadowsocksAddress() (address string) {
 	return ":" + value
 }
 
-func (r *Reader) readShadowsocksCipher() (cipher string) {
-	_, cipher = r.getEnvWithRetro("SHADOWSOCKS_CIPHER", "SHADOWSOCKS_METHOD")
+func (s *Source) readShadowsocksCipher() (cipher string) {
+	_, cipher = s.getEnvWithRetro("SHADOWSOCKS_CIPHER", "SHADOWSOCKS_METHOD")
 	return strings.ToLower(cipher)
 }

internal/configuration/sources/env/system.go

@@ -14,13 +14,13 @@ var (
 	ErrSystemTimezoneNotValid = errors.New("timezone is not valid")
 )
 
-func (r *Reader) readSystem() (system settings.System, err error) {
-	system.PUID, err = r.readID("PUID", "UID")
+func (s *Source) readSystem() (system settings.System, err error) {
+	system.PUID, err = s.readID("PUID", "UID")
 	if err != nil {
 		return system, err
 	}
 
-	system.PGID, err = r.readID("PGID", "GID")
+	system.PGID, err = s.readID("PGID", "GID")
 	if err != nil {
 		return system, err
 	}
@@ -32,9 +32,9 @@ func (r *Reader) readSystem() (system settings.System, err error) {
 
 var ErrSystemIDNotValid = errors.New("system ID is not valid")
 
-func (r *Reader) readID(key, retroKey string) (
+func (s *Source) readID(key, retroKey string) (
 	id *uint32, err error) {
-	idEnvKey, idString := r.getEnvWithRetro(key, retroKey)
+	idEnvKey, idString := s.getEnvWithRetro(key, retroKey)
 	if idString == "" {
 		return nil, nil //nolint:nilnil
 	}

internal/configuration/sources/env/system_test.go

@@ -74,8 +74,8 @@ func Test_Reader_readID(t *testing.T) {
 			setTestEnv(t, key, testCase.keyValue)
 			setTestEnv(t, retroKey, testCase.retroValue)
 
-			reader := &Reader{}
-			id, err := reader.readID(key, retroKey)
+			source := &Source{}
+			id, err := source.readID(key, retroKey)
 
 			assert.ErrorIs(t, err, testCase.errWrapped)
 			if err != nil {

internal/configuration/sources/env/vpn.go

@@ -7,20 +7,20 @@ import (
 	"github.com/qdm12/gluetun/internal/configuration/settings"
 )
 
-func (r *Reader) readVPN() (vpn settings.VPN, err error) {
+func (s *Source) readVPN() (vpn settings.VPN, err error) {
 	vpn.Type = strings.ToLower(getCleanedEnv("VPN_TYPE"))
 
-	vpn.Provider, err = r.readProvider(vpn.Type)
+	vpn.Provider, err = s.readProvider(vpn.Type)
 	if err != nil {
 		return vpn, fmt.Errorf("VPN provider: %w", err)
 	}
 
-	vpn.OpenVPN, err = r.readOpenVPN()
+	vpn.OpenVPN, err = s.readOpenVPN()
 	if err != nil {
 		return vpn, fmt.Errorf("OpenVPN: %w", err)
 	}
 
-	vpn.Wireguard, err = r.readWireguard()
+	vpn.Wireguard, err = s.readWireguard()
 	if err != nil {
 		return vpn, fmt.Errorf("wireguard: %w", err)
 	}

internal/configuration/sources/env/wireguard.go

@@ -3,27 +3,29 @@ package env
 import (
 	"fmt"
 	"net"
+	"os"
 	"strings"
 
 	"github.com/qdm12/gluetun/internal/configuration/settings"
 )
 
-func (r *Reader) readWireguard() (wireguard settings.Wireguard, err error) {
+func (s *Source) readWireguard() (wireguard settings.Wireguard, err error) {
 	defer func() {
 		err = unsetEnvKeys([]string{"WIREGUARD_PRIVATE_KEY", "WIREGUARD_PRESHARED_KEY"}, err)
 	}()
 	wireguard.PrivateKey = envToStringPtr("WIREGUARD_PRIVATE_KEY")
 	wireguard.PreSharedKey = envToStringPtr("WIREGUARD_PRESHARED_KEY")
-	_, wireguard.Interface = r.getEnvWithRetro("VPN_INTERFACE", "WIREGUARD_INTERFACE")
-	wireguard.Addresses, err = r.readWireguardAddresses()
+	_, wireguard.Interface = s.getEnvWithRetro("VPN_INTERFACE", "WIREGUARD_INTERFACE")
+	wireguard.Implementation = os.Getenv("WIREGUARD_IMPLEMENTATION")
+	wireguard.Addresses, err = s.readWireguardAddresses()
 	if err != nil {
 		return wireguard, err // already wrapped
 	}
 	return wireguard, nil
 }
 
-func (r *Reader) readWireguardAddresses() (addresses []net.IPNet, err error) {
-	key, addressesCSV := r.getEnvWithRetro("WIREGUARD_ADDRESSES", "WIREGUARD_ADDRESS")
+func (s *Source) readWireguardAddresses() (addresses []net.IPNet, err error) {
+	key, addressesCSV := s.getEnvWithRetro("WIREGUARD_ADDRESSES", "WIREGUARD_ADDRESS")
 	if addressesCSV == "" {
 		return nil, nil
 	}
@@ -31,6 +33,7 @@ func (r *Reader) readWireguardAddresses() (addresses []net.IPNet, err error) {
 	addressStrings := strings.Split(addressesCSV, ",")
 	addresses = make([]net.IPNet, len(addressStrings))
 	for i, addressString := range addressStrings {
+		addressString = strings.TrimSpace(addressString)
 		ip, ipNet, err := net.ParseCIDR(addressString)
 		if err != nil {
 			return nil, fmt.Errorf("environment variable %s: %w", key, err)

internal/configuration/sources/env/wireguardselection.go

@@ -9,14 +9,14 @@ import (
 	"github.com/qdm12/govalid/port"
 )
 
-func (r *Reader) readWireguardSelection() (
+func (s *Source) readWireguardSelection() (
 	selection settings.WireguardSelection, err error) {
-	selection.EndpointIP, err = r.readWireguardEndpointIP()
+	selection.EndpointIP, err = s.readWireguardEndpointIP()
 	if err != nil {
 		return selection, err
 	}
 
-	selection.EndpointPort, err = r.readWireguardCustomPort()
+	selection.EndpointPort, err = s.readWireguardCustomPort()
 	if err != nil {
 		return selection, err
 	}
@@ -28,29 +28,29 @@ func (r *Reader) readWireguardSelection() (
 
 var ErrIPAddressParse = errors.New("cannot parse IP address")
 
-func (r *Reader) readWireguardEndpointIP() (endpointIP net.IP, err error) {
-	key, s := r.getEnvWithRetro("VPN_ENDPOINT_IP", "WIREGUARD_ENDPOINT_IP")
-	if s == "" {
+func (s *Source) readWireguardEndpointIP() (endpointIP net.IP, err error) {
+	key, value := s.getEnvWithRetro("VPN_ENDPOINT_IP", "WIREGUARD_ENDPOINT_IP")
+	if value == "" {
 		return nil, nil
 	}
 
-	endpointIP = net.ParseIP(s)
+	endpointIP = net.ParseIP(value)
 	if endpointIP == nil {
 		return nil, fmt.Errorf("environment variable %s: %w: %s",
-			key, ErrIPAddressParse, s)
+			key, ErrIPAddressParse, value)
 	}
 
 	return endpointIP, nil
 }
 
-func (r *Reader) readWireguardCustomPort() (customPort *uint16, err error) {
-	key, s := r.getEnvWithRetro("VPN_ENDPOINT_PORT", "WIREGUARD_ENDPOINT_PORT")
-	if s == "" {
+func (s *Source) readWireguardCustomPort() (customPort *uint16, err error) {
+	key, value := s.getEnvWithRetro("VPN_ENDPOINT_PORT", "WIREGUARD_ENDPOINT_PORT")
+	if value == "" {
 		return nil, nil //nolint:nilnil
 	}
 
 	customPort = new(uint16)
-	*customPort, err = port.Validate(s)
+	*customPort, err = port.Validate(value)
 	if err != nil {
 		return nil, fmt.Errorf("environment variable %s: %w", key, err)
 	}

internal/configuration/sources/files/health.go

@@ -2,4 +2,4 @@ package files
 
 import "github.com/qdm12/gluetun/internal/configuration/settings"
 
-func (r *Reader) ReadHealth() (settings settings.Health, err error) { return settings, nil }
+func (s *Source) ReadHealth() (settings settings.Health, err error) { return settings, nil }

internal/configuration/sources/files/openvpn.go

@@ -14,7 +14,7 @@ const (
 	openVPNEncryptedKey          = "/gluetun/openvpn_encrypted_key"
 )
 
-func (r *Reader) readOpenVPN() (settings settings.OpenVPN, err error) {
+func (s *Source) readOpenVPN() (settings settings.OpenVPN, err error) {
 	settings.Key, err = readPEMFile(OpenVPNClientKeyPath)
 	if err != nil {
 		return settings, fmt.Errorf("client key: %w", err)

internal/configuration/sources/files/reader.go

@@ -2,26 +2,23 @@ package files
 
 import (
 	"github.com/qdm12/gluetun/internal/configuration/settings"
-	"github.com/qdm12/gluetun/internal/configuration/sources"
 )
 
-var _ sources.Source = (*Reader)(nil)
+type Source struct{}
 
-type Reader struct{}
-
-func New() *Reader {
-	return &Reader{}
+func New() *Source {
+	return &Source{}
 }
 
-func (r *Reader) String() string { return "files" }
+func (s *Source) String() string { return "files" }
 
-func (r *Reader) Read() (settings settings.Settings, err error) {
-	settings.VPN, err = r.readVPN()
+func (s *Source) Read() (settings settings.Settings, err error) {
+	settings.VPN, err = s.readVPN()
 	if err != nil {
 		return settings, err
 	}
 
-	settings.System, err = r.readSystem()
+	settings.System, err = s.readSystem()
 	if err != nil {
 		return settings, err
 	}

internal/configuration/sources/files/system.go

@@ -4,7 +4,7 @@ import (
 	"github.com/qdm12/gluetun/internal/configuration/settings"
 )
 
-func (r *Reader) readSystem() (system settings.System, err error) {
+func (s *Source) readSystem() (system settings.System, err error) {
 	// TODO timezone from /etc/localtime
 	return system, nil
 }

internal/configuration/sources/files/vpn.go

@@ -6,8 +6,8 @@ import (
 	"github.com/qdm12/gluetun/internal/configuration/settings"
 )
 
-func (r *Reader) readVPN() (vpn settings.VPN, err error) {
-	vpn.OpenVPN, err = r.readOpenVPN()
+func (s *Source) readVPN() (vpn settings.VPN, err error) {
+	vpn.OpenVPN, err = s.readOpenVPN()
 	if err != nil {
 		return vpn, fmt.Errorf("OpenVPN: %w", err)
 	}

internal/configuration/sources/merge/reader.go

@@ -1,29 +1,32 @@
-package mux
+package merge
 
 import (
 	"fmt"
 	"strings"
 
 	"github.com/qdm12/gluetun/internal/configuration/settings"
-	"github.com/qdm12/gluetun/internal/configuration/sources"
 )
 
-var _ sources.Source = (*Reader)(nil)
-
-type Reader struct {
-	sources []sources.Source
+type ConfigSource interface {
+	Read() (settings settings.Settings, err error)
+	ReadHealth() (settings settings.Health, err error)
+	String() string
 }
 
-func New(sources ...sources.Source) *Reader {
-	return &Reader{
+type Source struct {
+	sources []ConfigSource
+}
+
+func New(sources ...ConfigSource) *Source {
+	return &Source{
 		sources: sources,
 	}
 }
 
-func (r *Reader) String() string {
-	sources := make([]string, len(r.sources))
-	for i := range r.sources {
-		sources[i] = r.sources[i].String()
+func (s *Source) String() string {
+	sources := make([]string, len(s.sources))
+	for i := range s.sources {
+		sources[i] = s.sources[i].String()
 	}
 	return strings.Join(sources, ", ")
 }
@@ -31,8 +34,8 @@ func (r *Reader) String() string {
 // Read reads the settings for each source, merging unset fields
 // with field set by the next source.
 // It then set defaults to remaining unset fields.
-func (r *Reader) Read() (settings settings.Settings, err error) {
-	for _, source := range r.sources {
+func (s *Source) Read() (settings settings.Settings, err error) {
+	for _, source := range s.sources {
 		settingsFromSource, err := source.Read()
 		if err != nil {
 			return settings, fmt.Errorf("reading from %s: %w", source, err)
@@ -47,8 +50,8 @@ func (r *Reader) Read() (settings settings.Settings, err error) {
 // with field set by the next source.
 // It then set defaults to remaining unset fields, and validate
 // all the fields.
-func (r *Reader) ReadHealth() (settings settings.Health, err error) {
-	for _, source := range r.sources {
+func (s *Source) ReadHealth() (settings settings.Health, err error) {
+	for _, source := range s.sources {
 		settingsFromSource, err := source.ReadHealth()
 		if err != nil {
 			return settings, fmt.Errorf("reading from %s: %w", source, err)

internal/configuration/sources/secrets/health.go

@@ -2,4 +2,4 @@ package secrets
 
 import "github.com/qdm12/gluetun/internal/configuration/settings"
 
-func (r *Reader) ReadHealth() (settings settings.Health, err error) { return settings, nil }
+func (s *Source) ReadHealth() (settings settings.Health, err error) { return settings, nil }

internal/configuration/sources/secrets/httpproxy.go

@@ -12,7 +12,7 @@ func readHTTPProxy() (settings settings.HTTPProxy, err error) {
 		"/run/secrets/httpproxy_user",
 	)
 	if err != nil {
-		return settings, fmt.Errorf("cannot read HTTP proxy user secret file: %w", err)
+		return settings, fmt.Errorf("reading HTTP proxy user secret file: %w", err)
 	}
 
 	settings.Password, err = readSecretFileAsStringPtr(
@@ -20,7 +20,7 @@ func readHTTPProxy() (settings settings.HTTPProxy, err error) {
 		"/run/secrets/httpproxy_password",
 	)
 	if err != nil {
-		return settings, fmt.Errorf("cannot read OpenVPN password secret file: %w", err)
+		return settings, fmt.Errorf("reading OpenVPN password secret file: %w", err)
 	}
 
 	return settings, nil

internal/configuration/sources/secrets/openvpn.go

@@ -13,7 +13,7 @@ func readOpenVPN() (
 		"/run/secrets/openvpn_user",
 	)
 	if err != nil {
-		return settings, fmt.Errorf("cannot read user file: %w", err)
+		return settings, fmt.Errorf("reading user file: %w", err)
 	}
 
 	settings.Password, err = readSecretFileAsStringPtr(
@@ -21,7 +21,7 @@ func readOpenVPN() (
 		"/run/secrets/openvpn_password",
 	)
 	if err != nil {
-		return settings, fmt.Errorf("cannot read password file: %w", err)
+		return settings, fmt.Errorf("reading password file: %w", err)
 	}
 
 	settings.Key, err = readPEMSecretFile(
@@ -29,7 +29,7 @@ func readOpenVPN() (
 		"/run/secrets/openvpn_clientkey",
 	)
 	if err != nil {
-		return settings, fmt.Errorf("cannot read client key file: %w", err)
+		return settings, fmt.Errorf("reading client key file: %w", err)
 	}
 
 	settings.EncryptedKey, err = readPEMSecretFile(
@@ -53,7 +53,7 @@ func readOpenVPN() (
 		"/run/secrets/openvpn_clientcrt",
 	)
 	if err != nil {
-		return settings, fmt.Errorf("cannot read client certificate file: %w", err)
+		return settings, fmt.Errorf("reading client certificate file: %w", err)
 	}
 
 	return settings, nil

internal/configuration/sources/secrets/reader.go

@@ -2,21 +2,17 @@ package secrets
 
 import (
 	"github.com/qdm12/gluetun/internal/configuration/settings"
-	"github.com/qdm12/gluetun/internal/configuration/sources"
 )
 
-var _ sources.Source = (*Reader)(nil)
+type Source struct{}
 
-type Reader struct {
+func New() *Source {
+	return &Source{}
 }
 
-func New() *Reader {
-	return &Reader{}
-}
+func (s *Source) String() string { return "secret files" }
 
-func (r *Reader) String() string { return "secret files" }
-
-func (r *Reader) Read() (settings settings.Settings, err error) {
+func (s *Source) Read() (settings settings.Settings, err error) {
 	settings.VPN, err = readVPN()
 	if err != nil {
 		return settings, err

internal/configuration/sources/secrets/shadowsocks.go

@@ -12,7 +12,7 @@ func readShadowsocks() (settings settings.Shadowsocks, err error) {
 		"/run/secrets/shadowsocks_password",
 	)
 	if err != nil {
-		return settings, fmt.Errorf("cannot read Shadowsocks password secret file: %w", err)
+		return settings, fmt.Errorf("reading Shadowsocks password secret file: %w", err)
 	}
 
 	return settings, nil

internal/configuration/sources/secrets/vpn.go

@@ -9,7 +9,7 @@ import (
 func readVPN() (vpn settings.VPN, err error) {
 	vpn.OpenVPN, err = readOpenVPN()
 	if err != nil {
-		return vpn, fmt.Errorf("cannot read OpenVPN settings: %w", err)
+		return vpn, fmt.Errorf("reading OpenVPN settings: %w", err)
 	}
 
 	return vpn, nil

internal/constants/openvpn/ciphers.go

@@ -1,8 +1,11 @@
 package openvpn
 
 const (
-	AES128cbc = "aes-128-cbc"
-	AES256cbc = "aes-256-cbc"
-	AES128gcm = "aes-128-gcm"
-	AES256gcm = "aes-256-gcm"
+	AES128cbc        = "aes-128-cbc"
+	AES192cbc        = "aes-192-cbc"
+	AES256cbc        = "aes-256-cbc"
+	AES128gcm        = "aes-128-gcm"
+	AES192gcm        = "aes-192-gcm"
+	AES256gcm        = "aes-256-gcm"
+	Chacha20Poly1305 = "chacha20-poly1305"
 )

internal/constants/providers/providers.go

@@ -3,6 +3,7 @@ package providers
 const (
 	// Custom is the VPN provider name for custom
 	// VPN configurations.
+	Airvpn                = "airvpn"
 	Custom                = "custom"
 	Cyberghost            = "cyberghost"
 	Example               = "example"
@@ -32,6 +33,7 @@ const (
 // All returns all the providers except the custom provider.
 func All() []string {
 	return []string{
+		Airvpn,
 		Cyberghost,
 		Expressvpn,
 		Fastestvpn,

internal/firewall/cmd_matcher_test.go

@@ -48,7 +48,7 @@ func (cm *cmdMatcher) String() string {
 	return fmt.Sprintf("path %s, argument regular expressions %v", cm.path, cm.argsRegex)
 }
 
-func newCmdMatcher(path string, argsRegex ...string) *cmdMatcher { //nolint:unparam
+func newCmdMatcher(path string, argsRegex ...string) *cmdMatcher {
 	argsRegexp := make([]*regexp.Regexp, len(argsRegex))
 	for i, argRegex := range argsRegex {
 		argsRegexp[i] = regexp.MustCompile(argRegex)

internal/firewall/enable.go

@@ -21,7 +21,7 @@ func (c *Config) SetEnabled(ctx context.Context, enabled bool) (err error) {
 	if !enabled {
 		c.logger.Info("disabling...")
 		if err = c.disable(ctx); err != nil {
-			return fmt.Errorf("cannot disable firewall: %w", err)
+			return fmt.Errorf("disabling firewall: %w", err)
 		}
 		c.enabled = false
 		c.logger.Info("disabled successfully")
@@ -31,7 +31,7 @@ func (c *Config) SetEnabled(ctx context.Context, enabled bool) (err error) {
 	c.logger.Info("enabling...")
 
 	if err := c.enable(ctx); err != nil {
-		return fmt.Errorf("cannot enable firewall: %w", err)
+		return fmt.Errorf("enabling firewall: %w", err)
 	}
 	c.enabled = true
 	c.logger.Info("enabled successfully")
@@ -41,13 +41,13 @@ func (c *Config) SetEnabled(ctx context.Context, enabled bool) (err error) {
 
 func (c *Config) disable(ctx context.Context) (err error) {
 	if err = c.clearAllRules(ctx); err != nil {
-		return fmt.Errorf("cannot clear all rules: %w", err)
+		return fmt.Errorf("clearing all rules: %w", err)
 	}
 	if err = c.setIPv4AllPolicies(ctx, "ACCEPT"); err != nil {
-		return fmt.Errorf("cannot set ipv4 policies: %w", err)
+		return fmt.Errorf("setting ipv4 policies: %w", err)
 	}
 	if err = c.setIPv6AllPolicies(ctx, "ACCEPT"); err != nil {
-		return fmt.Errorf("cannot set ipv6 policies: %w", err)
+		return fmt.Errorf("setting ipv6 policies: %w", err)
 	}
 	return nil
 }
@@ -101,6 +101,9 @@ func (c *Config) enable(ctx context.Context) (err error) {
 		if err := c.acceptOutputFromIPToSubnet(ctx, network.InterfaceName, network.IP, *network.IPNet, remove); err != nil {
 			return err
 		}
+		if err = c.acceptIpv6MulticastOutput(ctx, network.InterfaceName, remove); err != nil {
+			return err
+		}
 	}
 
 	if err = c.allowOutboundSubnets(ctx); err != nil {
@@ -120,7 +123,7 @@ func (c *Config) enable(ctx context.Context) (err error) {
 	}
 
 	if err := c.runUserPostRules(ctx, c.customRulesPath, remove); err != nil {
-		return fmt.Errorf("cannot run user defined post firewall rules: %w", err)
+		return fmt.Errorf("running user defined post firewall rules: %w", err)
 	}
 
 	return nil
@@ -135,7 +138,7 @@ func (c *Config) allowVPNIP(ctx context.Context) (err error) {
 	for _, defaultRoute := range c.defaultRoutes {
 		err = c.acceptOutputTrafficToVPN(ctx, defaultRoute.NetInterface, c.vpnConnection, remove)
 		if err != nil {
-			return fmt.Errorf("cannot accept output traffic through VPN: %w", err)
+			return fmt.Errorf("accepting output traffic through VPN: %w", err)
 		}
 	}
 
@@ -162,7 +165,7 @@ func (c *Config) allowInputPorts(ctx context.Context) (err error) {
 			const remove = false
 			err = c.acceptInputToPort(ctx, netInterface, port, remove)
 			if err != nil {
-				return fmt.Errorf("cannot accept input port %d on interface %s: %w",
+				return fmt.Errorf("accepting input port %d on interface %s: %w",
 					port, netInterface, err)
 			}
 		}

internal/firewall/iptables.go

@@ -179,6 +179,18 @@ func (c *Config) acceptOutputFromIPToSubnet(ctx context.Context,
 	return c.runIP6tablesInstruction(ctx, instruction)
 }
 
+// NDP uses multicast address (theres no broadcast in IPv6 like ARP uses in IPv4).
+func (c *Config) acceptIpv6MulticastOutput(ctx context.Context,
+	intf string, remove bool) error {
+	interfaceFlag := "-o " + intf
+	if intf == "*" { // all interfaces
+		interfaceFlag = ""
+	}
+	instruction := fmt.Sprintf("%s OUTPUT %s -d ff02::1:ff/104 -j ACCEPT",
+		appendOrDelete(remove), interfaceFlag)
+	return c.runIP6tablesInstruction(ctx, instruction)
+}
+
 // Used for port forwarding, with intf set to tun.
 func (c *Config) acceptInputToPort(ctx context.Context, intf string, port uint16, remove bool) error {
 	interfaceFlag := "-i " + intf
@@ -245,7 +257,7 @@ func (c *Config) runUserPostRules(ctx context.Context, filepath string, remove b
 		case ipv4:
 			err = c.runIptablesInstruction(ctx, rule)
 		case c.ip6Tables == "":
-			err = fmt.Errorf("cannot run user ip6tables rule: %w", ErrNeedIP6Tables)
+			err = fmt.Errorf("running user ip6tables rule: %w", ErrNeedIP6Tables)
 		default: // ipv6
 			err = c.runIP6tablesInstruction(ctx, rule)
 		}

internal/firewall/outboundsubnets.go

@@ -28,7 +28,7 @@ func (c *Config) SetOutboundSubnets(ctx context.Context, subnets []net.IPNet) (e
 
 	c.removeOutboundSubnets(ctx, subnetsToRemove)
 	if err := c.addOutboundSubnets(ctx, subnetsToAdd); err != nil {
-		return fmt.Errorf("cannot set allowed outbound subnets: %w", err)
+		return fmt.Errorf("setting allowed outbound subnets: %w", err)
 	}
 
 	return nil

internal/firewall/ports.go

@@ -36,10 +36,11 @@ func (c *Config) SetAllowedPort(ctx context.Context, port uint16, intf string) (
 
 	const remove = false
 	if err := c.acceptInputToPort(ctx, intf, port, remove); err != nil {
-		return fmt.Errorf("cannot allow input to port %d through interface %s: %w",
+		return fmt.Errorf("allowing input to port %d through interface %s: %w",
 			port, intf, err)
 	}
 	netInterfaces[intf] = struct{}{}
+	c.allowedInputPorts[port] = netInterfaces
 
 	return nil
 }
@@ -69,7 +70,7 @@ func (c *Config) RemoveAllowedPort(ctx context.Context, port uint16) (err error)
 	for netInterface := range interfacesSet {
 		err := c.acceptInputToPort(ctx, netInterface, port, remove)
 		if err != nil {
-			return fmt.Errorf("cannot remove allowed port %d on interface %s: %w",
+			return fmt.Errorf("removing allowed port %d on interface %s: %w",
 				port, netInterface, err)
 		}
 		delete(interfacesSet, netInterface)

internal/firewall/support.go

@@ -6,6 +6,7 @@ import (
 	"fmt"
 	"math/rand"
 	"os/exec"
+	"sort"
 	"strings"
 
 	"github.com/qdm12/golibs/command"
@@ -20,7 +21,7 @@ var (
 
 func checkIptablesSupport(ctx context.Context, runner command.Runner,
 	iptablesPathsToTry ...string) (iptablesPath string, err error) {
-	var lastUnsupportedMessage string
+	iptablesPathToUnsupportedMessage := make(map[string]string, len(iptablesPathsToTry))
 	for _, pathToTest := range iptablesPathsToTry {
 		ok, unsupportedMessage, err := testIptablesPath(ctx, pathToTest, runner)
 		if err != nil {
@@ -29,17 +30,35 @@ func checkIptablesSupport(ctx context.Context, runner command.Runner,
 			iptablesPath = pathToTest
 			break
 		}
-
-		lastUnsupportedMessage = unsupportedMessage
+		iptablesPathToUnsupportedMessage[pathToTest] = unsupportedMessage
 	}
 
-	if iptablesPath == "" { // all iptables to try failed
-		return "", fmt.Errorf("%w: from %s: last error is: %s",
-			ErrIPTablesNotSupported, strings.Join(iptablesPathsToTry, ", "),
-			lastUnsupportedMessage)
+	if iptablesPath != "" {
+		// some paths may be unsupported but that does not matter
+		// since we found one working.
+		return iptablesPath, nil
 	}
 
-	return iptablesPath, nil
+	allArePermissionDenied := true
+	allUnsupportedMessages := make(sort.StringSlice, 0, len(iptablesPathToUnsupportedMessage))
+	for iptablesPath, unsupportedMessage := range iptablesPathToUnsupportedMessage {
+		if !isPermissionDenied(unsupportedMessage) {
+			allArePermissionDenied = false
+		}
+		unsupportedMessage = iptablesPath + ": " + unsupportedMessage
+		allUnsupportedMessages = append(allUnsupportedMessages, unsupportedMessage)
+	}
+
+	allUnsupportedMessages.Sort() // predictable order for tests
+
+	if allArePermissionDenied {
+		// If the error is related to a denied permission for all iptables path,
+		// return an error describing what to do from an end-user perspective.
+		return "", fmt.Errorf("%w: %s", ErrNetAdminMissing, strings.Join(allUnsupportedMessages, "; "))
+	}
+
+	return "", fmt.Errorf("%w: errors encountered are: %s",
+		ErrIPTablesNotSupported, strings.Join(allUnsupportedMessages, "; "))
 }
 
 func testIptablesPath(ctx context.Context, path string,
@@ -56,14 +75,6 @@ func testIptablesPath(ctx context.Context, path string,
 		"-A", "OUTPUT", "-o", testInterfaceName, "-j", "DROP")
 	output, err := runner.Run(cmd)
 	if err != nil {
-		if isPermissionDenied(output) {
-			// If the error is related to a denied permission,
-			// return an error describing what to do from an end-user
-			// perspective. This is a critical error and likely
-			// applies to all iptables.
-			criticalErr = fmt.Errorf("%w: %s", ErrNetAdminMissing, output)
-			return false, "", criticalErr
-		}
 		unsupportedMessage = fmt.Sprintf("%s (%s)", output, err)
 		return false, unsupportedMessage, nil
 	}
@@ -84,10 +95,6 @@ func testIptablesPath(ctx context.Context, path string,
 	cmd = exec.CommandContext(ctx, path, "-L", "INPUT")
 	output, err = runner.Run(cmd)
 	if err != nil {
-		if isPermissionDenied(output) {
-			criticalErr = fmt.Errorf("%w: %s", ErrNetAdminMissing, output)
-			return false, "", criticalErr
-		}
 		unsupportedMessage = fmt.Sprintf("%s (%s)", output, err)
 		return false, unsupportedMessage, nil
 	}
@@ -109,10 +116,6 @@ func testIptablesPath(ctx context.Context, path string,
 	cmd = exec.CommandContext(ctx, path, "--policy", "INPUT", inputPolicy)
 	output, err = runner.Run(cmd)
 	if err != nil {
-		if isPermissionDenied(output) {
-			criticalErr = fmt.Errorf("%w: %s", ErrNetAdminMissing, output)
-			return false, "", criticalErr
-		}
 		unsupportedMessage = fmt.Sprintf("%s (%s)", output, err)
 		return false, unsupportedMessage, nil
 	}

internal/firewall/support_test.go

@@ -8,10 +8,130 @@ import (
 	"github.com/golang/mock/gomock"
 	"github.com/qdm12/golibs/command"
 	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
 )
 
 //go:generate mockgen -destination=runner_mock_test.go -package $GOPACKAGE github.com/qdm12/golibs/command Runner
 
+func newAppendTestRuleMatcher(path string) *cmdMatcher {
+	return newCmdMatcher(path,
+		"^-A$", "^OUTPUT$", "^-o$", "^[a-z0-9]{15}$",
+		"^-j$", "^DROP$")
+}
+
+func newDeleteTestRuleMatcher(path string) *cmdMatcher {
+	return newCmdMatcher(path,
+		"^-D$", "^OUTPUT$", "^-o$", "^[a-z0-9]{15}$",
+		"^-j$", "^DROP$")
+}
+
+func newListInputRulesMatcher(path string) *cmdMatcher {
+	return newCmdMatcher(path,
+		"^-L$", "^INPUT$")
+}
+
+func newSetPolicyMatcher(path, inputPolicy string) *cmdMatcher { //nolint:unparam
+	return newCmdMatcher(path,
+		"^--policy$", "^INPUT$", "^"+inputPolicy+"$")
+}
+
+func Test_checkIptablesSupport(t *testing.T) {
+	t.Parallel()
+
+	ctx := context.Background()
+	errDummy := errors.New("exit code 4")
+	const inputPolicy = "ACCEPT"
+
+	testCases := map[string]struct {
+		buildRunner        func(ctrl *gomock.Controller) command.Runner
+		iptablesPathsToTry []string
+		iptablesPath       string
+		errSentinel        error
+		errMessage         string
+	}{
+		"critical error when checking": {
+			buildRunner: func(ctrl *gomock.Controller) command.Runner {
+				runner := NewMockRunner(ctrl)
+				runner.EXPECT().Run(newAppendTestRuleMatcher("path1")).
+					Return("", nil)
+				runner.EXPECT().Run(newDeleteTestRuleMatcher("path1")).
+					Return("output", errDummy)
+				return runner
+			},
+			iptablesPathsToTry: []string{"path1", "path2"},
+			errSentinel:        ErrTestRuleCleanup,
+			errMessage: "for path1: failed cleaning up test rule: " +
+				"output (exit code 4)",
+		},
+		"found valid path": {
+			buildRunner: func(ctrl *gomock.Controller) command.Runner {
+				runner := NewMockRunner(ctrl)
+				runner.EXPECT().Run(newAppendTestRuleMatcher("path1")).
+					Return("", nil)
+				runner.EXPECT().Run(newDeleteTestRuleMatcher("path1")).
+					Return("", nil)
+				runner.EXPECT().Run(newListInputRulesMatcher("path1")).
+					Return("Chain INPUT (policy "+inputPolicy+")", nil)
+				runner.EXPECT().Run(newSetPolicyMatcher("path1", inputPolicy)).
+					Return("", nil)
+				return runner
+			},
+			iptablesPathsToTry: []string{"path1", "path2"},
+			iptablesPath:       "path1",
+		},
+		"all permission denied": {
+			buildRunner: func(ctrl *gomock.Controller) command.Runner {
+				runner := NewMockRunner(ctrl)
+				runner.EXPECT().Run(newAppendTestRuleMatcher("path1")).
+					Return("Permission denied (you must be root) more context", errDummy)
+				runner.EXPECT().Run(newAppendTestRuleMatcher("path2")).
+					Return("context: Permission denied (you must be root)", errDummy)
+				return runner
+			},
+			iptablesPathsToTry: []string{"path1", "path2"},
+			errSentinel:        ErrNetAdminMissing,
+			errMessage: "NET_ADMIN capability is missing: " +
+				"path1: Permission denied (you must be root) more context (exit code 4); " +
+				"path2: context: Permission denied (you must be root) (exit code 4)",
+		},
+		"no valid path": {
+			buildRunner: func(ctrl *gomock.Controller) command.Runner {
+				runner := NewMockRunner(ctrl)
+				runner.EXPECT().Run(newAppendTestRuleMatcher("path1")).
+					Return("output 1", errDummy)
+				runner.EXPECT().Run(newAppendTestRuleMatcher("path2")).
+					Return("output 2", errDummy)
+				return runner
+			},
+			iptablesPathsToTry: []string{"path1", "path2"},
+			errSentinel:        ErrIPTablesNotSupported,
+			errMessage: "no iptables supported found: " +
+				"errors encountered are: " +
+				"path1: output 1 (exit code 4); " +
+				"path2: output 2 (exit code 4)",
+		},
+	}
+
+	for name, testCase := range testCases {
+		testCase := testCase
+		t.Run(name, func(t *testing.T) {
+			t.Parallel()
+			ctrl := gomock.NewController(t)
+
+			runner := testCase.buildRunner(ctrl)
+
+			iptablesPath, err :=
+				checkIptablesSupport(ctx, runner, testCase.iptablesPathsToTry...)
+
+			require.ErrorIs(t, err, testCase.errSentinel)
+			if testCase.errSentinel != nil {
+				assert.EqualError(t, err, testCase.errMessage)
+			}
+			assert.Equal(t, testCase.iptablesPath, iptablesPath)
+		})
+	}
+}
+
 func Test_testIptablesPath(t *testing.T) {
 	t.Parallel()
 
@@ -20,17 +140,6 @@ func Test_testIptablesPath(t *testing.T) {
 	errDummy := errors.New("exit code 4")
 	const inputPolicy = "ACCEPT"
 
-	appendTestRuleMatcher := newCmdMatcher(path,
-		"^-A$", "^OUTPUT$", "^-o$", "^[a-z0-9]{15}$",
-		"^-j$", "^DROP$")
-	deleteTestRuleMatcher := newCmdMatcher(path,
-		"^-D$", "^OUTPUT$", "^-o$", "^[a-z0-9]{15}$",
-		"^-j$", "^DROP$")
-	listInputRulesMatcher := newCmdMatcher(path,
-		"^-L$", "^INPUT$")
-	setPolicyMatcher := newCmdMatcher(path,
-		"^--policy$", "^INPUT$", "^"+inputPolicy+"$")
-
 	testCases := map[string]struct {
 		buildRunner        func(ctrl *gomock.Controller) command.Runner
 		ok                 bool
@@ -41,18 +150,16 @@ func Test_testIptablesPath(t *testing.T) {
 		"append test rule permission denied": {
 			buildRunner: func(ctrl *gomock.Controller) command.Runner {
 				runner := NewMockRunner(ctrl)
-				runner.EXPECT().Run(appendTestRuleMatcher).
+				runner.EXPECT().Run(newAppendTestRuleMatcher(path)).
 					Return("Permission denied (you must be root)", errDummy)
 				return runner
 			},
-			criticalErrWrapped: ErrNetAdminMissing,
-			criticalErrMessage: "NET_ADMIN capability is missing: " +
-				"Permission denied (you must be root)",
+			unsupportedMessage: "Permission denied (you must be root) (exit code 4)",
 		},
 		"append test rule unsupported": {
 			buildRunner: func(ctrl *gomock.Controller) command.Runner {
 				runner := NewMockRunner(ctrl)
-				runner.EXPECT().Run(appendTestRuleMatcher).
+				runner.EXPECT().Run(newAppendTestRuleMatcher(path)).
 					Return("some output", errDummy)
 				return runner
 			},
@@ -61,8 +168,8 @@ func Test_testIptablesPath(t *testing.T) {
 		"remove test rule error": {
 			buildRunner: func(ctrl *gomock.Controller) command.Runner {
 				runner := NewMockRunner(ctrl)
-				runner.EXPECT().Run(appendTestRuleMatcher).Return("", nil)
-				runner.EXPECT().Run(deleteTestRuleMatcher).
+				runner.EXPECT().Run(newAppendTestRuleMatcher(path)).Return("", nil)
+				runner.EXPECT().Run(newDeleteTestRuleMatcher(path)).
 					Return("some output", errDummy)
 				return runner
 			},
@@ -72,22 +179,20 @@ func Test_testIptablesPath(t *testing.T) {
 		"list input rules permission denied": {
 			buildRunner: func(ctrl *gomock.Controller) command.Runner {
 				runner := NewMockRunner(ctrl)
-				runner.EXPECT().Run(appendTestRuleMatcher).Return("", nil)
-				runner.EXPECT().Run(deleteTestRuleMatcher).Return("", nil)
-				runner.EXPECT().Run(listInputRulesMatcher).
+				runner.EXPECT().Run(newAppendTestRuleMatcher(path)).Return("", nil)
+				runner.EXPECT().Run(newDeleteTestRuleMatcher(path)).Return("", nil)
+				runner.EXPECT().Run(newListInputRulesMatcher(path)).
 					Return("Permission denied (you must be root)", errDummy)
 				return runner
 			},
-			criticalErrWrapped: ErrNetAdminMissing,
-			criticalErrMessage: "NET_ADMIN capability is missing: " +
-				"Permission denied (you must be root)",
+			unsupportedMessage: "Permission denied (you must be root) (exit code 4)",
 		},
 		"list input rules unsupported": {
 			buildRunner: func(ctrl *gomock.Controller) command.Runner {
 				runner := NewMockRunner(ctrl)
-				runner.EXPECT().Run(appendTestRuleMatcher).Return("", nil)
-				runner.EXPECT().Run(deleteTestRuleMatcher).Return("", nil)
-				runner.EXPECT().Run(listInputRulesMatcher).
+				runner.EXPECT().Run(newAppendTestRuleMatcher(path)).Return("", nil)
+				runner.EXPECT().Run(newDeleteTestRuleMatcher(path)).Return("", nil)
+				runner.EXPECT().Run(newListInputRulesMatcher(path)).
 					Return("some output", errDummy)
 				return runner
 			},
@@ -96,9 +201,9 @@ func Test_testIptablesPath(t *testing.T) {
 		"list input rules no policy": {
 			buildRunner: func(ctrl *gomock.Controller) command.Runner {
 				runner := NewMockRunner(ctrl)
-				runner.EXPECT().Run(appendTestRuleMatcher).Return("", nil)
-				runner.EXPECT().Run(deleteTestRuleMatcher).Return("", nil)
-				runner.EXPECT().Run(listInputRulesMatcher).
+				runner.EXPECT().Run(newAppendTestRuleMatcher(path)).Return("", nil)
+				runner.EXPECT().Run(newDeleteTestRuleMatcher(path)).Return("", nil)
+				runner.EXPECT().Run(newListInputRulesMatcher(path)).
 					Return("some\noutput", nil)
 				return runner
 			},
@@ -108,26 +213,24 @@ func Test_testIptablesPath(t *testing.T) {
 		"set policy permission denied": {
 			buildRunner: func(ctrl *gomock.Controller) command.Runner {
 				runner := NewMockRunner(ctrl)
-				runner.EXPECT().Run(appendTestRuleMatcher).Return("", nil)
-				runner.EXPECT().Run(deleteTestRuleMatcher).Return("", nil)
-				runner.EXPECT().Run(listInputRulesMatcher).
+				runner.EXPECT().Run(newAppendTestRuleMatcher(path)).Return("", nil)
+				runner.EXPECT().Run(newDeleteTestRuleMatcher(path)).Return("", nil)
+				runner.EXPECT().Run(newListInputRulesMatcher(path)).
 					Return("\nChain INPUT (policy "+inputPolicy+")\nxx\n", nil)
-				runner.EXPECT().Run(setPolicyMatcher).
+				runner.EXPECT().Run(newSetPolicyMatcher(path, inputPolicy)).
 					Return("Permission denied (you must be root)", errDummy)
 				return runner
 			},
-			criticalErrWrapped: ErrNetAdminMissing,
-			criticalErrMessage: "NET_ADMIN capability is missing: " +
-				"Permission denied (you must be root)",
+			unsupportedMessage: "Permission denied (you must be root) (exit code 4)",
 		},
 		"set policy unsupported": {
 			buildRunner: func(ctrl *gomock.Controller) command.Runner {
 				runner := NewMockRunner(ctrl)
-				runner.EXPECT().Run(appendTestRuleMatcher).Return("", nil)
-				runner.EXPECT().Run(deleteTestRuleMatcher).Return("", nil)
-				runner.EXPECT().Run(listInputRulesMatcher).
+				runner.EXPECT().Run(newAppendTestRuleMatcher(path)).Return("", nil)
+				runner.EXPECT().Run(newDeleteTestRuleMatcher(path)).Return("", nil)
+				runner.EXPECT().Run(newListInputRulesMatcher(path)).
 					Return("\nChain INPUT (policy "+inputPolicy+")\nxx\n", nil)
-				runner.EXPECT().Run(setPolicyMatcher).
+				runner.EXPECT().Run(newSetPolicyMatcher(path, inputPolicy)).
 					Return("some output", errDummy)
 				return runner
 			},
@@ -136,11 +239,12 @@ func Test_testIptablesPath(t *testing.T) {
 		"success": {
 			buildRunner: func(ctrl *gomock.Controller) command.Runner {
 				runner := NewMockRunner(ctrl)
-				runner.EXPECT().Run(appendTestRuleMatcher).Return("", nil)
-				runner.EXPECT().Run(deleteTestRuleMatcher).Return("", nil)
-				runner.EXPECT().Run(listInputRulesMatcher).
+				runner.EXPECT().Run(newAppendTestRuleMatcher(path)).Return("", nil)
+				runner.EXPECT().Run(newDeleteTestRuleMatcher(path)).Return("", nil)
+				runner.EXPECT().Run(newListInputRulesMatcher(path)).
 					Return("\nChain INPUT (policy "+inputPolicy+")\nxx\n", nil)
-				runner.EXPECT().Run(setPolicyMatcher).Return("some output", nil)
+				runner.EXPECT().Run(newSetPolicyMatcher(path, inputPolicy)).
+					Return("some output", nil)
 				return runner
 			},
 			ok: true,

internal/firewall/vpn.go

@@ -45,13 +45,13 @@ func (c *Config) SetVPNConnection(ctx context.Context,
 
 	for _, defaultRoute := range c.defaultRoutes {
 		if err := c.acceptOutputTrafficToVPN(ctx, defaultRoute.NetInterface, connection, remove); err != nil {
-			return fmt.Errorf("cannot allow output traffic through VPN connection: %w", err)
+			return fmt.Errorf("allowing output traffic through VPN connection: %w", err)
 		}
 	}
 	c.vpnConnection = connection
 
 	if err = c.acceptOutputThroughInterface(ctx, vpnIntf, remove); err != nil {
-		return fmt.Errorf("cannot accept output traffic through interface %s: %w", vpnIntf, err)
+		return fmt.Errorf("accepting output traffic through interface %s: %w", vpnIntf, err)
 	}
 	c.vpnIntf = vpnIntf
 

internal/healthcheck/health.go

@@ -74,12 +74,12 @@ func (s *Server) healthCheck(ctx context.Context) (err error) {
 	const dialNetwork = "tcp4"
 	connection, err := s.dialer.DialContext(ctx, dialNetwork, address)
 	if err != nil {
-		return fmt.Errorf("cannot dial: %w", err)
+		return fmt.Errorf("dialing: %w", err)
 	}
 
 	err = connection.Close()
 	if err != nil {
-		return fmt.Errorf("cannot close connection: %w", err)
+		return fmt.Errorf("closing connection: %w", err)
 	}
 
 	return nil
@@ -91,7 +91,7 @@ func makeAddressToDial(address string) (addressToDial string, err error) {
 		addrErr := new(net.AddrError)
 		ok := errors.As(err, &addrErr)
 		if !ok || addrErr.Err != "missing port in address" {
-			return "", fmt.Errorf("cannot split host and port from address: %w", err)
+			return "", fmt.Errorf("splitting host and port from address: %w", err)
 		}
 		host = address
 		const defaultPort = "443"

internal/healthcheck/health_test.go

@@ -85,7 +85,7 @@ func Test_makeAddressToDial(t *testing.T) {
 		},
 		"bad address": {
 			address: "test.com::",
-			err:     fmt.Errorf("cannot split host and port from address: address test.com::: too many colons in address"), //nolint:lll
+			err:     fmt.Errorf("splitting host and port from address: address test.com::: too many colons in address"), //nolint:lll
 		},
 	}
 

internal/healthcheck/openvpn.go

@@ -15,7 +15,8 @@ type vpnHealth struct {
 
 func (s *Server) onUnhealthyVPN(ctx context.Context) {
 	s.logger.Info("program has been unhealthy for " +
-		s.vpn.healthyWait.String() + ": restarting VPN")
+		s.vpn.healthyWait.String() + ": restarting VPN " +
+		"(see https://github.com/qdm12/gluetun/wiki/Healthcheck)")
 	_, _ = s.vpn.loop.ApplyStatus(ctx, constants.Stopped)
 	_, _ = s.vpn.loop.ApplyStatus(ctx, constants.Running)
 	s.vpn.healthyWait += *s.config.VPN.Addition

internal/httpproxy/auth.go

@@ -2,6 +2,7 @@ package httpproxy
 
 import (
 	"encoding/base64"
+	"fmt"
 	"net/http"
 	"strings"
 )
@@ -32,7 +33,8 @@ func (h *handler) isAuthorized(responseWriter http.ResponseWriter, request *http
 		return false
 	}
 	if h.username != usernamePassword[0] || h.password != usernamePassword[1] {
-		h.logger.Info("Username or password mismatch from " + request.RemoteAddr)
+		h.logger.Info(fmt.Sprintf("Username (%q) or password (%q) mismatch from %s",
+			usernamePassword[0], usernamePassword[1], request.RemoteAddr))
 		h.logger.Debug("username provided \"" + usernamePassword[0] +
 			"\" and password provided \"" + usernamePassword[1] + "\"")
 		responseWriter.WriteHeader(http.StatusUnauthorized)

internal/httpproxy/server.go

@@ -39,7 +39,7 @@ func (s *Server) Run(ctx context.Context, errorCh chan<- error) {
 	}
 	go func() {
 		<-ctx.Done()
-		const shutdownGraceDuration = 2 * time.Second
+		const shutdownGraceDuration = 100 * time.Millisecond
 		shutdownCtx, cancel := context.WithTimeout(context.Background(), shutdownGraceDuration)
 		defer cancel()
 		if err := server.Shutdown(shutdownCtx); err != nil {

internal/models/markdown.go

@@ -5,6 +5,7 @@ import (
 	"strings"
 
 	"github.com/qdm12/gluetun/internal/constants/providers"
+	"github.com/qdm12/gluetun/internal/constants/vpn"
 )
 
 func boolToMarkdown(b bool) string {
@@ -26,6 +27,7 @@ const (
 	hostnameHeader    = "Hostname"
 	ispHeader         = "ISP"
 	multiHopHeader    = "MultiHop"
+	nameHeader        = "Name"
 	numberHeader      = "Number"
 	ownedHeader       = "Owned"
 	portForwardHeader = "Port forwarding"
@@ -57,6 +59,8 @@ func (s *Server) ToMarkdown(headers ...string) (markdown string) {
 			fields[i] = s.ISP
 		case multiHopHeader:
 			fields[i] = boolToMarkdown(s.MultiHop)
+		case nameHeader:
+			fields[i] = s.ServerName
 		case numberHeader:
 			fields[i] = fmt.Sprint(s.Number)
 		case ownedHeader:
@@ -72,7 +76,7 @@ func (s *Server) ToMarkdown(headers ...string) (markdown string) {
 		case tcpHeader:
 			fields[i] = boolToMarkdown(s.TCP)
 		case udpHeader:
-			fields[i] = boolToMarkdown(s.UDP)
+			fields[i] = boolToMarkdown(s.UDP || s.VPN == vpn.Wireguard)
 		case vpnHeader:
 			fields[i] = s.VPN
 		}
@@ -98,6 +102,9 @@ func (s *Servers) ToMarkdown(vpnProvider string) (markdown string) {
 
 func getMarkdownHeaders(vpnProvider string) (headers []string) {
 	switch vpnProvider {
+	case providers.Airvpn:
+		return []string{regionHeader, countryHeader, cityHeader, vpnHeader,
+			udpHeader, tcpHeader, hostnameHeader, nameHeader}
 	case providers.Cyberghost:
 		return []string{countryHeader, hostnameHeader, tcpHeader, udpHeader}
 	case providers.Expressvpn:

internal/models/server.go

@@ -39,7 +39,8 @@ var (
 	ErrVPNFieldEmpty           = errors.New("vpn field is empty")
 	ErrHostnameFieldEmpty      = errors.New("hostname field is empty")
 	ErrIPsFieldEmpty           = errors.New("ips field is empty")
-	ErrNoNetworkProtocol       = errors.New("both TCP and UDP fields are false")
+	ErrNoNetworkProtocol       = errors.New("both TCP and UDP fields are false for OpenVPN")
+	ErrNetworkProtocolSet      = errors.New("no network protocol should be set")
 	ErrWireguardPublicKeyEmpty = errors.New("wireguard public key field is empty")
 )
 
@@ -51,7 +52,9 @@ func (s *Server) HasMinimumInformation() (err error) {
 		return ErrHostnameFieldEmpty
 	case len(s.IPs) == 0:
 		return ErrIPsFieldEmpty
-	case !s.TCP && !s.UDP:
+	case s.VPN == vpn.Wireguard && (s.TCP || s.UDP):
+		return ErrNetworkProtocolSet
+	case s.VPN == vpn.OpenVPN && !s.TCP && !s.UDP:
 		return ErrNoNetworkProtocol
 	case s.VPN == vpn.Wireguard && s.WgPubKey == "":
 		return ErrWireguardPublicKeyEmpty

internal/models/servers.go

@@ -27,13 +27,13 @@ func (a *AllServers) MarshalJSON() (data []byte, err error) {
 
 	_, err = buffer.WriteString("{")
 	if err != nil {
-		return nil, fmt.Errorf("cannot write opening bracket: %w", err)
+		return nil, fmt.Errorf("writing opening bracket: %w", err)
 	}
 
 	versionString := fmt.Sprintf(`"version":%d`, a.Version)
 	_, err = buffer.WriteString(versionString)
 	if err != nil {
-		return nil, fmt.Errorf("cannot write schema version string: %w", err)
+		return nil, fmt.Errorf("writing schema version string: %w", err)
 	}
 
 	sortedProviders := make(sort.StringSlice, 0, len(a.ProviderToServers))
@@ -46,26 +46,26 @@ func (a *AllServers) MarshalJSON() (data []byte, err error) {
 		providerKey := fmt.Sprintf(`,"%s":`, provider)
 		_, err = buffer.WriteString(providerKey)
 		if err != nil {
-			return nil, fmt.Errorf("cannot write provider key %s: %w",
+			return nil, fmt.Errorf("writing provider key %s: %w",
 				providerKey, err)
 		}
 
 		servers := a.ProviderToServers[provider]
 		serversJSON, err := json.Marshal(servers)
 		if err != nil {
-			return nil, fmt.Errorf("failed encoding servers for provider %s: %w",
+			return nil, fmt.Errorf("encoding servers for provider %s: %w",
 				provider, err)
 		}
 		_, err = buffer.Write(serversJSON)
 		if err != nil {
-			return nil, fmt.Errorf("cannot write JSON servers data for provider %s: %w",
+			return nil, fmt.Errorf("writing JSON servers data for provider %s: %w",
 				provider, err)
 		}
 	}
 
 	_, err = buffer.WriteString("}")
 	if err != nil {
-		return nil, fmt.Errorf("cannot write closing bracket: %w", err)
+		return nil, fmt.Errorf("writing closing bracket: %w", err)
 	}
 
 	return buffer.Bytes(), nil
@@ -127,14 +127,14 @@ func (a *AllServers) UnmarshalJSON(data []byte) (err error) {
 
 		jsonValue, err := json.Marshal(value)
 		if err != nil {
-			return fmt.Errorf("cannot marshal %s servers: %w",
+			return fmt.Errorf("encoding %s servers: %w",
 				key, err)
 		}
 
 		var servers Servers
 		err = json.Unmarshal(jsonValue, &servers)
 		if err != nil {
-			return fmt.Errorf("cannot unmarshal %s servers: %w",
+			return fmt.Errorf("decoding %s servers: %w",
 				key, err)
 		}
 

internal/netlink/family.go

@@ -16,7 +16,7 @@ const (
 func (n *NetLink) IsWireguardSupported() (ok bool, err error) {
 	families, err := netlink.GenlFamilyList()
 	if err != nil {
-		return false, fmt.Errorf("cannot list gen 1 families: %w", err)
+		return false, fmt.Errorf("listing gen 1 families: %w", err)
 	}
 	for _, family := range families {
 		if family.Name == "wireguard" {

internal/netlink/interfaces.go

@@ -0,0 +1,8 @@
+package netlink
+
+import "github.com/qdm12/log"
+
+type DebugLogger interface {
+	Debugf(format string, args ...any)
+	Patch(options ...log.Option)
+}

internal/netlink/ipv6.go

@@ -0,0 +1,40 @@
+package netlink
+
+import (
+	"fmt"
+
+	"github.com/vishvananda/netlink"
+)
+
+func (n *NetLink) IsIPv6Supported() (supported bool, err error) {
+	links, err := n.LinkList()
+	if err != nil {
+		return false, fmt.Errorf("listing links: %w", err)
+	}
+
+	var totalRoutes uint
+	for _, link := range links {
+		routes, err := n.RouteList(link, netlink.FAMILY_V6)
+		if err != nil {
+			return false, fmt.Errorf("listing IPv6 routes for link %s: %w",
+				link.Attrs().Name, err)
+		}
+
+		// Check each route for IPv6 due to Podman bug listing IPv4 routes
+		// as IPv6 routes at container start, see:
+		// https://github.com/qdm12/gluetun/issues/1241#issuecomment-1333405949
+		for _, route := range routes {
+			sourceIsIPv6 := route.Src != nil && route.Src.To4() == nil
+			destinationIsIPv6 := route.Dst != nil && route.Dst.IP.To4() == nil
+			if sourceIsIPv6 || destinationIsIPv6 {
+				n.debugLogger.Debugf("IPv6 is supported by link %s", link.Attrs().Name)
+				return true, nil
+			}
+			totalRoutes++
+		}
+	}
+
+	n.debugLogger.Debugf("IPv6 is not supported after searching %d links and %d routes",
+		len(links), totalRoutes)
+	return false, nil
+}

internal/netlink/netlink.go

@@ -1,7 +1,17 @@
 package netlink
 
-type NetLink struct{}
+import "github.com/qdm12/log"
 
-func New() *NetLink {
-	return &NetLink{}
+type NetLink struct {
+	debugLogger DebugLogger
+}
+
+func New(debugLogger DebugLogger) *NetLink {
+	return &NetLink{
+		debugLogger: debugLogger,
+	}
+}
+
+func (n *NetLink) PatchLoggerLevel(level log.Level) {
+	n.debugLogger.Patch(log.SetLevel(level))
 }

internal/openvpn/extract/data.go

@@ -17,12 +17,12 @@ func (e *Extractor) Data(filepath string) (lines []string,
 	connection models.Connection, err error) {
 	lines, err = readCustomConfigLines(filepath)
 	if err != nil {
-		return nil, connection, fmt.Errorf("cannot read configuration file: %w", err)
+		return nil, connection, fmt.Errorf("reading configuration file: %w", err)
 	}
 
 	connection, err = extractDataFromLines(lines)
 	if err != nil {
-		return nil, connection, fmt.Errorf("cannot extract connection from file: %w", err)
+		return nil, connection, fmt.Errorf("extracting connection from file: %w", err)
 	}
 
 	return lines, connection, nil

internal/openvpn/extract/extract.go

@@ -54,14 +54,14 @@ func extractDataFromLine(line string) (
 	case strings.HasPrefix(line, "proto "):
 		protocol, err = extractProto(line)
 		if err != nil {
-			return nil, 0, "", fmt.Errorf("failed extracting protocol from proto line: %w", err)
+			return nil, 0, "", fmt.Errorf("extracting protocol from proto line: %w", err)
 		}
 		return nil, 0, protocol, nil
 
 	case strings.HasPrefix(line, "remote "):
 		ip, port, protocol, err = extractRemote(line)
 		if err != nil {
-			return nil, 0, "", fmt.Errorf("failed extracting from remote line: %w", err)
+			return nil, 0, "", fmt.Errorf("extracting from remote line: %w", err)
 		}
 		return ip, port, protocol, nil
 	}
@@ -81,7 +81,7 @@ func extractProto(line string) (protocol string, err error) {
 	}
 
 	switch fields[1] {
-	case "tcp", "udp":
+	case "tcp", "tcp4", "tcp6", "udp", "udp4", "udp6":
 	default:
 		return "", fmt.Errorf("%w: %s", errProtocolNotSupported, fields[1])
 	}

internal/openvpn/extract/extract_test.go

@@ -29,7 +29,7 @@ func Test_extractDataFromLines(t *testing.T) {
 		},
 		"extraction error": {
 			lines: []string{"bla bla", "proto bad", "remote 1.2.3.4 1194 tcp"},
-			err:   errors.New("on line 2: failed extracting protocol from proto line: network protocol not supported: bad"),
+			err:   errors.New("on line 2: extracting protocol from proto line: network protocol not supported: bad"),
 		},
 		"only use first values found": {
 			lines: []string{"proto udp", "proto tcp", "remote 1.2.3.4 443 tcp", "remote 5.2.3.4 1194 udp"},

internal/openvpn/extract/pem.go

@@ -1,33 +1,23 @@
 package extract
 
 import (
+	"encoding/base64"
 	"encoding/pem"
 	"errors"
-	"regexp"
-	"strings"
+	"fmt"
 )
 
 var (
 	errPEMDecode = errors.New("cannot decode PEM encoded block")
 )
 
-var (
-	regexPEMBegin = regexp.MustCompile(`-----BEGIN [A-Za-z ]+-----`)
-	regexPEMEnd   = regexp.MustCompile(`-----END [A-Za-z ]+-----`)
-)
-
 func PEM(b []byte) (encodedData string, err error) {
 	pemBlock, _ := pem.Decode(b)
 	if pemBlock == nil {
-		return "", errPEMDecode
+		return "", fmt.Errorf("%w", errPEMDecode)
 	}
 
-	encodedBytes := pem.EncodeToMemory(pemBlock)
-	encodedData = string(encodedBytes)
-	encodedData = strings.ReplaceAll(encodedData, "\n", "")
-	beginPrefix := regexPEMBegin.FindString(encodedData)
-	encodedData = strings.TrimPrefix(encodedData, beginPrefix)
-	endPrefix := regexPEMEnd.FindString(encodedData)
-	encodedData = strings.TrimSuffix(encodedData, endPrefix)
+	der := pemBlock.Bytes
+	encodedData = base64.StdEncoding.EncodeToString(der)
 	return encodedData, nil
 }

internal/openvpn/extract/pem_test.go

@@ -1,6 +1,7 @@
 package extract
 
 import (
+	"bytes"
 	"testing"
 
 	"github.com/stretchr/testify/assert"
@@ -24,6 +25,14 @@ func Test_PEM(t *testing.T) {
 			errWrapped: errPEMDecode,
 			errMessage: "cannot decode PEM encoded block",
 		},
+		"valid data with extras": {
+			b: bytes.Join([][]byte{
+				{1, 2, 3},
+				[]byte(validCertPEM),
+				{4, 5, 6},
+			}, []byte("\n")),
+			encodedData: validCertData,
+		},
 		"valid data": {
 			b:           []byte(validCertPEM),
 			encodedData: validCertData,

internal/openvpn/logs.go

@@ -65,6 +65,16 @@ That error usually happens because either:
 		filtered = s
 		level = levelInfo
 	}
+
+	switch {
+	case filtered == "RTNETLINK answers: File exists":
+		filtered = "OpenVPN tried to add an IP route which already exists (" + filtered + ")"
+		level = levelWarn
+	case strings.HasPrefix(filtered, "Linux route add command failed: "):
+		filtered = "Previous error details: " + filtered
+		level = levelWarn
+	}
+
 	filtered = constants.ColorOpenvpn().Sprintf(filtered)
 	return filtered, level
 }

internal/openvpn/logs_test.go

@@ -43,6 +43,36 @@ func Test_processLogLine(t *testing.T) {
 			"AUTH: Received control message: AUTH_FAILED",
 			"AUTH: Received control message: AUTH_FAILED\n\nYour credentials might be wrong 🤨\n\n",
 			levelError},
+		"TLS key negotiation error": {
+			s: "TLS Error: TLS key negotiation failed to occur within " +
+				"60 seconds (check your network connectivity)",
+			filtered: "TLS Error: TLS key negotiation failed to occur within " +
+				"60 seconds (check your network connectivity)" + `
+🚒🚒🚒🚒🚒🚨🚨🚨🚨🚨🚨🚒🚒🚒🚒🚒
+That error usually happens because either:
+
+1. The VPN server IP address you are trying to connect to is no longer valid 🔌
+   Update your server information using https://github.com/qdm12/gluetun/wiki/Updating-Servers
+
+2. The VPN server crashed 💥, try changing your VPN servers filtering options such as SERVER_REGIONS
+
+3. Your Internet connection is not working 🤯, ensure it works
+
+4. Something else ➡️ https://github.com/qdm12/gluetun/issues/new/choose
+`,
+			level: levelWarn,
+		},
+		"RTNETLINK answers: File exists": {
+			s: "ERROR: RTNETLINK answers: File exists",
+			filtered: "OpenVPN tried to add an IP route which already exists " +
+				"(RTNETLINK answers: File exists)",
+			level: levelWarn,
+		},
+		"Linux route add command failed": {
+			s:        "ERROR: Linux route add command failed: some error",
+			filtered: "Previous error details: Linux route add command failed: some error",
+			level:    levelWarn,
+		},
 	}
 	for name, tc := range tests {
 		tc := tc

internal/openvpn/pkcs8/algorithms.go

@@ -0,0 +1,53 @@
+package pkcs8
+
+import (
+	"crypto/x509/pkix"
+	"encoding/asn1"
+	"errors"
+	"fmt"
+)
+
+var (
+	// Algorithm identifiers are listed at
+	// https://www.ibm.com/docs/en/zos/2.3.0?topic=programming-object-identifiers
+	oidDESCBC = asn1.ObjectIdentifier{1, 3, 14, 3, 2, 7} //nolint:gochecknoglobals
+)
+
+var (
+	ErrEncryptionAlgorithmNotPBES2 = errors.New("encryption algorithm is not PBES2")
+)
+
+type encryptedPrivateKey struct {
+	EncryptionAlgorithm pkix.AlgorithmIdentifier
+	EncryptedData       []byte
+}
+
+type encryptedAlgorithmParams struct {
+	KeyDerivationFunc pkix.AlgorithmIdentifier
+	EncryptionScheme  pkix.AlgorithmIdentifier
+}
+
+func getEncryptionAlgorithmOid(der []byte) (
+	encryptionSchemeAlgorithm asn1.ObjectIdentifier, err error) {
+	var encryptedPrivateKeyData encryptedPrivateKey
+	_, err = asn1.Unmarshal(der, &encryptedPrivateKeyData)
+	if err != nil {
+		return nil, fmt.Errorf("decoding asn1 encrypted private key data: %w", err)
+	}
+
+	oidPBES2 := asn1.ObjectIdentifier{1, 2, 840, 113549, 1, 5, 13}
+	oidAlgorithm := encryptedPrivateKeyData.EncryptionAlgorithm.Algorithm
+	if !oidAlgorithm.Equal(oidPBES2) {
+		return nil, fmt.Errorf("%w: %s instead of PBES2 %s",
+			ErrEncryptionAlgorithmNotPBES2, oidAlgorithm, oidPBES2)
+	}
+
+	var encryptionAlgorithmParams encryptedAlgorithmParams
+	paramBytes := encryptedPrivateKeyData.EncryptionAlgorithm.Parameters.FullBytes
+	_, err = asn1.Unmarshal(paramBytes, &encryptionAlgorithmParams)
+	if err != nil {
+		return nil, fmt.Errorf("decoding asn1 encryption algorithm parameters: %w", err)
+	}
+
+	return encryptionAlgorithmParams.EncryptionScheme.Algorithm, nil
+}

internal/openvpn/pkcs8/algorithms_test.go

@@ -0,0 +1,106 @@
+package pkcs8
+
+import (
+	"crypto/x509/pkix"
+	"encoding/asn1"
+	"encoding/pem"
+	"errors"
+	"fmt"
+	"os"
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
+	pkcs8lib "github.com/youmark/pkcs8"
+)
+
+func Test_getEncryptionAlgorithmOid(t *testing.T) {
+	t.Parallel()
+
+	testCases := map[string]struct {
+		makeDER                   func() (der []byte, err error)
+		encryptionSchemeAlgorithm asn1.ObjectIdentifier
+		errMessage                string
+	}{
+		"empty data": {
+			makeDER: func() (der []byte, err error) { return nil, nil },
+			errMessage: "decoding asn1 encrypted private key data: " +
+				"asn1: syntax error: sequence truncated",
+		},
+		"algorithm not pbes2": {
+			makeDER: func() (der []byte, err error) {
+				data := encryptedPrivateKey{
+					EncryptionAlgorithm: pkix.AlgorithmIdentifier{
+						Algorithm: asn1.ObjectIdentifier{1, 2, 3, 4},
+					},
+				}
+				return asn1.Marshal(data)
+			},
+			errMessage: "encryption algorithm is not PBES2: " +
+				"1.2.3.4 instead of PBES2 1.2.840.113549.1.5.13",
+		},
+		"empty params full bytes": {
+			makeDER: func() (der []byte, err error) {
+				data := encryptedPrivateKey{
+					EncryptionAlgorithm: pkix.AlgorithmIdentifier{
+						Algorithm: asn1.ObjectIdentifier{1, 2, 840, 113549, 1, 5, 13},
+						Parameters: asn1.RawValue{
+							FullBytes: []byte{},
+						},
+					},
+				}
+				return asn1.Marshal(data)
+			},
+			errMessage: "decoding asn1 encryption algorithm parameters: " +
+				"asn1: structure error: tags don't match " +
+				"(16 vs {class:0 tag:0 length:0 isCompound:false}) {optional:false explicit:false application:false private:false defaultValue:<nil> tag:<nil> stringType:0 timeType:0 set:false omitEmpty:false} encryptedAlgorithmParams @2", //nolint:lll
+		},
+		"DES-CBC DER": {
+			makeDER: func() (der []byte, err error) {
+				DESCBCEncryptedPEM, err := os.ReadFile("testdata/rsa_pkcs8_descbc_encrypted.pem")
+				if err != nil {
+					return nil, fmt.Errorf("reading file: %w", err)
+				}
+				pemBlock, _ := pem.Decode(DESCBCEncryptedPEM)
+				if pemBlock == nil {
+					return nil, errors.New("failed to decode PEM")
+				}
+				return pemBlock.Bytes, nil
+			},
+			encryptionSchemeAlgorithm: oidDESCBC,
+		},
+		"AES-128-CBC DER": {
+			makeDER: func() (der []byte, err error) {
+				AES128CBCEncryptedPEM, err := os.ReadFile("testdata/rsa_pkcs8_aes128cbc_encrypted.pem")
+				if err != nil {
+					return nil, fmt.Errorf("reading file: %w", err)
+				}
+				pemBlock, _ := pem.Decode(AES128CBCEncryptedPEM)
+				if pemBlock == nil {
+					return nil, errors.New("failed to decode PEM")
+				}
+				return pemBlock.Bytes, nil
+			},
+			encryptionSchemeAlgorithm: pkcs8lib.AES128CBC.OID(),
+		},
+	}
+
+	for name, testCase := range testCases {
+		testCase := testCase
+		t.Run(name, func(t *testing.T) {
+			t.Parallel()
+
+			der, err := testCase.makeDER()
+			require.NoError(t, err)
+
+			encryptionSchemeAlgorithm, err := getEncryptionAlgorithmOid(der)
+
+			if testCase.errMessage != "" {
+				assert.EqualError(t, err, testCase.errMessage)
+			} else {
+				assert.NoError(t, err)
+			}
+			assert.Equal(t, testCase.encryptionSchemeAlgorithm, encryptionSchemeAlgorithm)
+		})
+	}
+}

internal/openvpn/pkcs8/descbc.go

@@ -0,0 +1,59 @@
+package pkcs8
+
+import (
+	"bytes"
+	"crypto/cipher"
+	"crypto/des" //nolint:gosec
+	"encoding/asn1"
+	"fmt"
+
+	pkcs8lib "github.com/youmark/pkcs8"
+)
+
+func init() { //nolint:gochecknoinits
+	pkcs8lib.RegisterCipher(oidDESCBC, newCipherDESCBCBlock)
+}
+
+func newCipherDESCBCBlock() pkcs8lib.Cipher { //nolint:ireturn
+	return cipherDESCBC{}
+}
+
+type cipherDESCBC struct{}
+
+func (c cipherDESCBC) IVSize() int {
+	return des.BlockSize
+}
+
+func (c cipherDESCBC) KeySize() int {
+	return 8 //nolint:gomnd
+}
+
+func (c cipherDESCBC) OID() asn1.ObjectIdentifier {
+	return oidDESCBC
+}
+
+func (c cipherDESCBC) Encrypt(key, iv, plaintext []byte) ([]byte, error) {
+	block, err := des.NewCipher(key) //nolint:gosec
+	if err != nil {
+		return nil, fmt.Errorf("creating DES cipher: %w", err)
+	}
+	blockEncrypter := cipher.NewCBCEncrypter(block, iv)
+	paddingLen := block.BlockSize() - (len(plaintext) % block.BlockSize())
+	ciphertext := make([]byte, len(plaintext)+paddingLen)
+	copy(ciphertext, plaintext)
+	copy(ciphertext[len(plaintext):],
+		bytes.Repeat([]byte{byte(paddingLen)}, paddingLen))
+	blockEncrypter.CryptBlocks(ciphertext, ciphertext)
+	return ciphertext, nil
+}
+
+func (c cipherDESCBC) Decrypt(key, iv, ciphertext []byte) ([]byte, error) {
+	block, err := des.NewCipher(key) //nolint:gosec
+	if err != nil {
+		return nil, fmt.Errorf("creating DES cipher: %w", err)
+	}
+	blockDecrypter := cipher.NewCBCDecrypter(block, iv)
+	plaintext := make([]byte, len(ciphertext))
+	blockDecrypter.CryptBlocks(plaintext, ciphertext)
+	return plaintext, nil
+}

internal/openvpn/pkcs8/testdata/readme.txt

@@ -0,0 +1,12 @@
+The key files in this directory are generated using OpenSSL.
+Re-generating them is fine and should work with existing tests.
+
+For DES encrypted RSA key files, openssl version 1.x.x is required, and the following commands in order generate the files:
+
+openssl genpkey -algorithm RSA -pkeyopt rsa_keygen_bits:512 -des -pass pass:password -out rsa_pkcs8_aes128cbc_encrypted.pem
+openssl pkcs8 -topk8 -in rsa_pkcs8_aes128cbc_encrypted.pem -passin pass:password -nocrypt -out rsa_pkcs8_aes128cbc_decrypted.pem
+
+For AES encrypted RSA key files, the following commands in order generate the files:
+
+openssl genpkey -algorithm RSA -pkeyopt rsa_keygen_bits:512 -aes-128-cbc -pass pass:password -out rsa_pkcs8_descbc_encrypted.pem
+openssl pkcs8 -topk8 -in rsa_pkcs8_descbc_encrypted.pem -passin pass:password -nocrypt -out rsa_pkcs8_descbc_decrypted.pem

internal/openvpn/pkcs8/testdata/rsa_pkcs8_aes128cbc_decrypted.pem

@@ -0,0 +1,10 @@
+-----BEGIN PRIVATE KEY-----
+MIIBVgIBADANBgkqhkiG9w0BAQEFAASCAUAwggE8AgEAAkEAsont6TMS9RVqjXoi
+wF/oKZCwbWM4HmCJvp5Z2dOfKabt+7FOTJiD7APLJKva6791HDTuyBu7+HFQCzW3
+ghLuiwIDAQABAkB09FuwHq/1cmEJao+nO2xHBiw8i/lwFMdG4k5znegujL4g16i7
++afWrMd54jYNPGiKuSNObB2BZR1j8tz/jvbxAiEA3d7bVwtWdaZVIV5t9uqrq5fG
+j3eXfNemTu1HQDmVqNMCIQDOALECY98KURR4NJueTKNuvawkuWFhizfKKTfS5B6Q
+aQIhANsF/RFYp+lMYg2m4nc2AnJKSkGmlW0wlYSkyAmmzw7xAiEAqSz+MSVNnU5a
+ziD+D/GGYkKYJYysgYvwZDCXbLT0uMkCIQDZghteTq2MMwIWWUJti3nc6nCICaJu
+d5O9Sm7BcOSuoA==
+-----END PRIVATE KEY-----

internal/openvpn/pkcs8/testdata/rsa_pkcs8_aes128cbc_encrypted.pem

@@ -0,0 +1,12 @@
+-----BEGIN ENCRYPTED PRIVATE KEY-----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+-----END ENCRYPTED PRIVATE KEY-----

internal/openvpn/pkcs8/testdata/rsa_pkcs8_descbc_decrypted.pem

@@ -0,0 +1,10 @@
+-----BEGIN PRIVATE KEY-----
+MIIBVgIBADANBgkqhkiG9w0BAQEFAASCAUAwggE8AgEAAkEAuU3FTtbPm8OjZ/d8
+vVd+seQcrCGgwxigKpOszFfOOXKxfy2CgpjE1Ga2h0UneJ6pq0KZyY+ggYAX8PaS
+U6R3HwIDAQABAkEAibQPkjzz3u8Nua8i1Zn1nsDDxe7fhtv/+mPvn5MIv4sFRS71
+0o9+SPNIQn7aJcGIqyBzHYdQg3/wGla+LA+msQIhAOt+hy1dnaWTSXIrIuPt+sSP
+Fjk80ijfxntXHNU6qExjAiEAyXBurrTdQs6D61ZzdlOFzgUs/FHa4dmWmxXuFsdv
+8RUCIQCIZQJaLiyOp94UOBO/PCjQC6ftguKeNe25plzWy2CKzQIgXBpBMTZXGG2u
+WZMcldSYkFtDd1bB2pQPTXeYdefYYgUCIQDVH3ysySFXIlHJulgcxvriXTfY4goY
+TQ0PL0Ow7sIz6A==
+-----END PRIVATE KEY-----

internal/openvpn/pkcs8/testdata/rsa_pkcs8_descbc_encrypted.pem

@@ -0,0 +1,12 @@
+-----BEGIN ENCRYPTED PRIVATE KEY-----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+-----END ENCRYPTED PRIVATE KEY-----

internal/openvpn/pkcs8/upgrade.go

@@ -0,0 +1,52 @@
+package pkcs8
+
+import (
+	"encoding/base64"
+	"errors"
+	"fmt"
+
+	pkcs8lib "github.com/youmark/pkcs8"
+)
+
+var (
+	ErrUnsupportedKeyType = errors.New("unsupported key type")
+)
+
+// UpgradeEncryptedKey eventually upgrades an encrypted key to a newer encryption
+// if its encryption is too weak for Openvpn/Openssl.
+// If the key is encrypted using DES-CBC, it is decrypted and re-encrypted using AES-256-CBC.
+// Otherwise, the key is returned unmodified.
+// Note this function only supports:
+// - PKCS8 encrypted keys
+// - RSA and ECDSA keys
+// - DES-CBC, 3DES, AES-128-CBC, AES-192-CBC, AES-256-CBC, AES-128-GCM, AES-192-GCM
+// and AES-256-GCM encryption algorithms.
+func UpgradeEncryptedKey(encryptedPKCS8DERKey, passphrase string) (securelyEncryptedPKCS8DERKey string, err error) {
+	der, err := base64.StdEncoding.DecodeString(encryptedPKCS8DERKey)
+	if err != nil {
+		return "", fmt.Errorf("decoding base64 encoded DER: %w", err)
+	}
+
+	oidEncryptionAlgorithm, err := getEncryptionAlgorithmOid(der)
+	if err != nil {
+		return "", fmt.Errorf("finding encryption algorithm oid: %w", err)
+	}
+
+	if !oidEncryptionAlgorithm.Equal(oidDESCBC) {
+		return encryptedPKCS8DERKey, nil
+	}
+
+	// Convert DES-CBC encrypted key to an AES256CBC encrypted key
+	privateKey, err := pkcs8lib.ParsePKCS8PrivateKey(der, []byte(passphrase))
+	if err != nil {
+		return "", fmt.Errorf("parsing pkcs8 encrypted private key: %w", err)
+	}
+
+	der, err = pkcs8lib.MarshalPrivateKey(privateKey, []byte(passphrase), pkcs8lib.DefaultOpts)
+	if err != nil {
+		return "", fmt.Errorf("encrypting and encoding private key: %w", err)
+	}
+
+	securelyEncryptedPKCS8DERKey = base64.StdEncoding.EncodeToString(der)
+	return securelyEncryptedPKCS8DERKey, nil
+}

internal/openvpn/pkcs8/upgrade_test.go

@@ -0,0 +1,75 @@
+package pkcs8
+
+import (
+	"crypto/x509"
+	"encoding/base64"
+	"encoding/pem"
+	"os"
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
+	"github.com/youmark/pkcs8"
+)
+
+func parsePEMFile(t *testing.T, pemFilepath string) (base64DER string) {
+	t.Helper()
+
+	bytes, err := os.ReadFile(pemFilepath)
+	require.NoError(t, err)
+
+	pemBlock, _ := pem.Decode(bytes)
+	require.NotNil(t, pemBlock)
+
+	derBytes := pemBlock.Bytes
+	base64DER = base64.StdEncoding.EncodeToString(derBytes)
+	return base64DER
+}
+
+func Test_UpgradeEncryptedKey(t *testing.T) {
+	t.Parallel()
+
+	testCases := map[string]struct {
+		encryptedPKCS8base64DERKey string
+		passphrase                 string
+		decryptedPKCS8Base64DERKey string
+		errMessage                 string
+	}{
+		"AES-128-CBC key": {
+			encryptedPKCS8base64DERKey: parsePEMFile(t, "testdata/rsa_pkcs8_aes128cbc_encrypted.pem"),
+			passphrase:                 "password",
+			decryptedPKCS8Base64DERKey: parsePEMFile(t, "testdata/rsa_pkcs8_aes128cbc_decrypted.pem"),
+		},
+		"DES-CBC key": {
+			encryptedPKCS8base64DERKey: parsePEMFile(t, "testdata/rsa_pkcs8_descbc_encrypted.pem"),
+			passphrase:                 "password",
+			decryptedPKCS8Base64DERKey: parsePEMFile(t, "testdata/rsa_pkcs8_descbc_decrypted.pem"),
+		},
+	}
+
+	for name, testCase := range testCases {
+		testCase := testCase
+		t.Run(name, func(t *testing.T) {
+			t.Parallel()
+
+			securelyEncryptedPKCS8DERKey, err := UpgradeEncryptedKey(testCase.encryptedPKCS8base64DERKey, testCase.passphrase)
+
+			if testCase.errMessage != "" {
+				assert.EqualError(t, err, testCase.errMessage)
+				return
+			}
+			assert.NoError(t, err)
+
+			// Decrypt possible re-encrypted key to verify it matches the expected
+			// corresponding decrypted key.
+			der, err := base64.StdEncoding.DecodeString(securelyEncryptedPKCS8DERKey)
+			require.NoError(t, err)
+			privateKey, err := pkcs8.ParsePKCS8PrivateKey(der, []byte(testCase.passphrase))
+			require.NoError(t, err)
+			der, err = x509.MarshalPKCS8PrivateKey(privateKey)
+			require.NoError(t, err)
+			base64DER := base64.StdEncoding.EncodeToString(der)
+			assert.Equal(t, testCase.decryptedPKCS8Base64DERKey, base64DER)
+		})
+	}
+}

internal/provider/airvpn/connection.go

@@ -0,0 +1,14 @@
+package airvpn
+
+import (
+	"github.com/qdm12/gluetun/internal/configuration/settings"
+	"github.com/qdm12/gluetun/internal/models"
+	"github.com/qdm12/gluetun/internal/provider/utils"
+)
+
+func (p *Provider) GetConnection(selection settings.ServerSelection, ipv6Supported bool) (
+	connection models.Connection, err error) {
+	defaults := utils.NewConnectionDefaults(443, 1194, 1637) //nolint:gomnd
+	return utils.GetConnection(p.Name(),
+		p.storage, selection, defaults, ipv6Supported, p.randSource)
+}