feat(nordvpn): filter with SERVER_CATEGORIES (#1806)

- update NordVPN servers data built-in

.devcontainer/Dockerfile

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

.devcontainer/README.md

@@ -9,17 +9,21 @@ It works on Linux, Windows and OSX.
 - [VS code](https://code.visualstudio.com/download) installed
 - [VS code remote containers extension](https://marketplace.visualstudio.com/items?itemName=ms-vscode-remote.remote-containers) installed
 - [Docker](https://www.docker.com/products/docker-desktop) installed and running
-    - If you don't use Linux or WSL 2, share your home directory `~/` and the directory of your project with Docker Desktop
 - [Docker Compose](https://docs.docker.com/compose/install/) installed
-- Ensure your host has the following and that they are accessible by Docker:
-    - `~/.ssh` directory
-    - `~/.gitconfig` file (can be empty)
 
 ## Setup
 
+1. Create the following files on your host if you don't have them:
+
+    ```sh
+    touch ~/.gitconfig ~/.zsh_history
+    ```
+
+    Note that the development container will create the empty directories `~/.docker`, `~/.ssh` and `~/.kube` if you don't have them.
+
+1. **For Docker on OSX or Windows without WSL**: ensure your home directory `~` is accessible by Docker.
 1. Open the command palette in Visual Studio Code (CTRL+SHIFT+P).
 1. Select `Remote-Containers: Open Folder in Container...` and choose the project directory.
-1. For Docker running on Windows HyperV, if you want to use SSH keys, bind mount them at `/tmp/.ssh` by changing the `volumes` section in the [docker-compose.yml](docker-compose.yml).
 
 ## Customization
 
@@ -29,13 +33,9 @@ You can make changes to the [Dockerfile](Dockerfile) and then rebuild the image.
 
 ```Dockerfile
 FROM qmcgaw/godevcontainer
-USER root
 RUN apk add curl
-USER vscode
 ```
 
-Note that you may need to use `USER root` to build as root, and then change back to `USER vscode`.
-
 To rebuild the image, either:
 
 - With VSCode through the command palette, select `Remote-Containers: Rebuild and reopen in container`
@@ -47,11 +47,11 @@ You can customize **settings** and **extensions** in the [devcontainer.json](dev
 
 ### Entrypoint script
 
-You can bind mount a shell script to `/home/vscode/.welcome.sh` to replace the [current welcome script](shell/.welcome.sh).
+You can bind mount a shell script to `/root/.welcome.sh` to replace the [current welcome script](https://github.com/qdm12/godevcontainer/blob/master/shell/.welcome.sh).
 
 ### Publish a port
 
-To access a port from your host to your development container, publish a port in [docker-compose.yml](docker-compose.yml).
+To access a port from your host to your development container, publish a port in [docker-compose.yml](docker-compose.yml). You can also now do it directly with VSCode without restarting the container.
 
 ### Run other services
 

.devcontainer/devcontainer.json

@@ -1,82 +1,73 @@
-{
-    "name": "gluetun-dev",
-    "dockerComposeFile": [
-        "docker-compose.yml"
-    ],
-    "service": "vscode",
-    "runServices": [
-        "vscode"
-    ],
-    "shutdownAction": "stopCompose",
-    "postCreateCommand": "source ~/.windows.sh && go mod download && go mod tidy",
-    "workspaceFolder": "/workspace",
-    "extensions": [
-        "golang.go",
-        "eamodio.gitlens", // IDE Git information
-        "davidanson.vscode-markdownlint",
-        "ms-azuretools.vscode-docker", // Docker integration and linting
-        "shardulm94.trailing-spaces", // Show trailing spaces
-        "Gruntfuggly.todo-tree", // Highlights TODO comments
-        "bierner.emojisense", // Emoji sense for markdown
-        "stkb.rewrap", // rewrap comments after n characters on one line
-        "vscode-icons-team.vscode-icons", // Better file extension icons
-        "github.vscode-pull-request-github", // Github interaction
-        "redhat.vscode-yaml", // Kubernetes, Drone syntax highlighting
-        "bajdzis.vscode-database", // Supports connections to mysql or postgres, over SSL, socked
-        "IBM.output-colorizer", // Colorize your output/test logs
-        "mohsen1.prettify-json", // Prettify JSON data
-        "github.copilot",
-    ],
-    "settings": {
-        "files.eol": "\n",
-        "remote.extensionKind": {
-            "ms-azuretools.vscode-docker": "workspace"
-        },
-        "editor.codeActionsOnSaveTimeout": 3000,
-        "go.useLanguageServer": true,
-        "[go]": {
-            "editor.formatOnSave": true,
-            "editor.codeActionsOnSave": {
-                "source.organizeImports": true,
-            },
-            // Optional: Disable snippets, as they conflict with completion ranking.
-            "editor.snippetSuggestions": "none"
-        },
-        "[go.mod]": {
-            "editor.formatOnSave": true,
-            "editor.codeActionsOnSave": {
-                "source.organizeImports": true,
-            },
-        },
-        "gopls": {
-            "usePlaceholders": false,
-            "staticcheck": true
-        },
-        "go.autocompleteUnimportedPackages": true,
-        "go.gotoSymbol.includeImports": true,
-        "go.gotoSymbol.includeGoroot": true,
-        "go.lintTool": "golangci-lint",
-        "go.buildOnSave": "workspace",
-        "go.lintOnSave": "workspace",
-        "go.vetOnSave": "workspace",
-        "editor.formatOnSave": true,
-        "go.toolsEnvVars": {
-            "GOFLAGS": "-tags=",
-            // "CGO_ENABLED": 1 // for the race detector
-        },
-        "gopls.env": {
-            "GOFLAGS": "-tags="
-        },
-        "go.testEnvVars": {
-            "": ""
-        },
-        "go.testFlags": [
-            "-v",
-            // "-race"
-        ],
-        "go.testTimeout": "10s",
-        "go.coverOnSingleTest": true,
-        "go.coverOnSingleTestFile": true,
-        "go.coverOnTestPackage": true
-    }
+{
+    "name": "gluetun-dev",
+    "dockerComposeFile": [
+        "docker-compose.yml"
+    ],
+    "service": "vscode",
+    "runServices": [
+        "vscode"
+    ],
+    "shutdownAction": "stopCompose",
+    "postCreateCommand": "~/.windows.sh && go mod download && go mod tidy",
+    "workspaceFolder": "/workspace",
+    // "overrideCommand": "",
+    "customizations": {
+        "vscode": {
+            "extensions": [
+                "golang.go",
+                "eamodio.gitlens", // IDE Git information
+                "davidanson.vscode-markdownlint",
+                "ms-azuretools.vscode-docker", // Docker integration and linting
+                "shardulm94.trailing-spaces", // Show trailing spaces
+                "Gruntfuggly.todo-tree", // Highlights TODO comments
+                "bierner.emojisense", // Emoji sense for markdown
+                "stkb.rewrap", // rewrap comments after n characters on one line
+                "vscode-icons-team.vscode-icons", // Better file extension icons
+                "github.vscode-pull-request-github", // Github interaction
+                "redhat.vscode-yaml", // Kubernetes, Drone syntax highlighting
+                "bajdzis.vscode-database", // Supports connections to mysql or postgres, over SSL, socked
+                "IBM.output-colorizer", // Colorize your output/test logs
+                "github.copilot" // AI code completion
+            ],
+            "settings": {
+                "files.eol": "\n",
+                "remote.extensionKind": {
+                    "ms-azuretools.vscode-docker": "workspace"
+                },
+                "go.useLanguageServer": true,
+                "[go]": {
+                    "editor.codeActionsOnSave": {
+                        "source.organizeImports": true
+                    }
+                },
+                "[go.mod]": {
+                    "editor.codeActionsOnSave": {
+                        "source.organizeImports": true
+                    }
+                },
+                "gopls": {
+                    "usePlaceholders": false,
+                    "staticcheck": true
+                },
+                "go.lintTool": "golangci-lint",
+                "go.lintOnSave": "package",
+                "editor.formatOnSave": true,
+                "go.buildTags": "linux",
+                "go.toolsEnvVars": {
+                    "CGO_ENABLED": "0"
+                },
+                "go.testEnvVars": {
+                    "CGO_ENABLED": "1"
+                },
+                "go.testFlags": [
+                    "-v",
+                    "-race"
+                ],
+                "go.testTimeout": "10s",
+                "go.coverOnSingleTest": true,
+                "go.coverOnSingleTestFile": true,
+                "go.coverOnTestPackage": true
+            }
+        }
+    }
 }

.devcontainer/docker-compose.yml

@@ -1,32 +1,28 @@
-version: "3.7"
-
-services:
-  vscode:
-    build: .
-    devices:
-      - /dev/net/tun:/dev/net/tun
-    volumes:
-      - ../:/workspace
-      # Docker socket to access Docker server
-      - /var/run/docker.sock:/var/run/docker.sock
-      # 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
-      # Shell history persistence
-      - ~/.zsh_history:/root/.zsh_history
-      # Git config
-      - ~/.gitconfig:/root/.gitconfig
-    environment:
-      - TZ=
-    cap_add:
-      # For debugging with dlv
-      # - SYS_PTRACE
-      - NET_ADMIN
-    security_opt:
-      # For debugging with dlv
-      - seccomp:unconfined
-    entrypoint: zsh -c "while sleep 1000; do :; done"
+version: "3.7"
+
+services:
+  vscode:
+    build: .
+    volumes:
+      - ../:/workspace
+      # Docker socket to access Docker server
+      - /var/run/docker.sock:/var/run/docker.sock
+      # SSH directory for Linux, OSX and WSL
+      # 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
+      - ~/.gitconfig:/root/.gitconfig
+    environment:
+      - TZ=
+    cap_add:
+      # For debugging with dlv
+      - SYS_PTRACE
+      - NET_ADMIN
+    security_opt:
+      # For debugging with dlv
+      - seccomp:unconfined
+    entrypoint: [ "zsh", "-c", "while sleep 1000; do :; done" ]

.github/CONTRIBUTING.md

@@ -13,6 +13,6 @@ Contributions are [released](https://help.github.com/articles/github-terms-of-se
 
 ## Resources
 
-- [Gluetun guide on development](https://github.com/qdm12/gluetun/wiki/Development)
+- [Gluetun guide on development](https://github.com/qdm12/gluetun-wiki/blob/main/contributing/development.md)
 - [Using Pull Requests](https://help.github.com/articles/about-pull-requests/)
 - [How to Contribute to Open Source](https://opensource.guide/how-to-contribute/)

.github/ISSUE_TEMPLATE/bug.yml

@@ -7,13 +7,18 @@ body:
     attributes:
       value: |
         Thanks for taking the time to fill out this bug report!
+
+        ⚠️ Your issue will be instantly closed as not planned WITHOUT explanation if:
+        - you do not fill out **the title of the issue** ☝️
+        - you do not provide the **Gluetun version** as requested below
+        - you provide **less than 10 lines of logs** as requested below
   - type: dropdown
     id: urgent
     attributes:
       label: Is this urgent?
       description: |
         Is this a critical bug, or do you need this fixed urgently?
-        If this is urgent, note you can use one of the [image tags available](https://github.com/qdm12/gluetun/wiki/Docker-image-tags) if that can help.
+        If this is urgent, note you can use one of the [image tags available](https://github.com/qdm12/gluetun-wiki/blob/main/setup/docker-image-tags.md) if that can help.
       options:
         - "No"
         - "Yes"
@@ -40,6 +45,7 @@ body:
     attributes:
       label: VPN service provider
       options:
+        - AirVPN
         - Custom
         - Cyberghost
         - ExpressVPN
@@ -54,8 +60,10 @@ body:
         - PrivateVPN
         - ProtonVPN
         - PureVPN
+        - SlickVPN
         - Surfshark
         - TorGuard
+        - VPNSecure.me
         - VPNUnlimited
         - VyprVPN
         - WeVPN
@@ -72,6 +80,7 @@ body:
         - Portainer
         - Kubernetes
         - Podman
+        - Unraid
         - Other
     validations:
       required: true
@@ -81,7 +90,7 @@ body:
       label: What is the version of Gluetun
       description: |
         Copy paste the version line at the top of your logs.
-        It should be in the form `Running version latest built on 2020-03-13T01:30:06Z (commit d0f678c)`.
+        It MUST be in the form `Running version latest built on 2020-03-13T01:30:06Z (commit d0f678c)`.
     validations:
       required: true
   - type: textarea
@@ -94,7 +103,7 @@ body:
   - type: textarea
     id: logs
     attributes:
-      label: Share your logs
+      label: Share your logs (at least 10 lines)
       description: No sensitive information is logged out except when running with `LOG_LEVEL=debug`.
       render: plain text
     validations:

.github/ISSUE_TEMPLATE/config.yml

@@ -1,4 +1,7 @@
 contact_links:
+  - name: Report a Wiki issue
+    url: https://github.com/qdm12/gluetun-wiki/issues/new
+    about: Please create an issue on the gluetun-wiki repository.
   - name: Configuration help?
     url: https://github.com/qdm12/gluetun/discussions/new
     about: Please create a Github discussion.

.github/ISSUE_TEMPLATE/provider.md

@@ -14,4 +14,4 @@ One of the following is required:
 
 If the list of servers requires to login **or** is hidden behind an interactive configurator,
 you can only use a custom Openvpn configuration file.
-[The Wiki](https://github.com/qdm12/gluetun/wiki/Openvpn-file) describes how to do so.
+[The Wiki's OpenVPN configuration file page](https://github.com/qdm12/gluetun-wiki/blob/main/setup/openvpn-configuration-file.md) describes how to do so.

.github/ISSUE_TEMPLATE/wiki issue.yml

@@ -1,18 +0,0 @@
-name: Wiki issue
-description: Report a Wiki issue
-title: "Wiki issue: "
-labels: ["📄 Wiki issue"]
-body:
-  - type: input
-    id: url
-    attributes:
-      label: "URL to the Wiki page"
-      placeholder: "https://github.com/qdm12/gluetun/wiki/OpenVPN-options"
-    validations:
-      required: true
-  - type: textarea
-    id: description
-    attributes:
-      label: "What's the issue?"
-    validations:
-      required: true

.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: ""
@@ -64,12 +70,17 @@
 - name: ":cloud: PureVPN"
   color: "cfe8d4"
   description: ""
+- name: ":cloud: SlickVPN"
+  color: "cfe8d4"
+  description: ""
 - name: ":cloud: Surfshark"
   color: "cfe8d4"
   description: ""
 - name: ":cloud: Torguard"
   color: "cfe8d4"
   description: ""
+- name: ":cloud: VPNSecure.me"
+  color: "cfe8d4"
 - name: ":cloud: VPNUnlimited"
   color: "cfe8d4"
   description: ""
@@ -84,6 +95,9 @@
   description: ""
 
 # Problem category
+- name: "Config problem"
+  color: "ffc7ea"
+  description: ""
 - name: "Openvpn"
   color: "ffc7ea"
   description: ""
@@ -96,6 +110,15 @@
 - name: "Firewall"
   color: "ffc7ea"
   description: ""
+- name: "Routing"
+  color: "ffc7ea"
+  description: ""
+- name: "IPv6"
+  color: "ffc7ea"
+  description: ""
+- name: "Port forwarding"
+  color: "ffc7ea"
+  description: ""
 - name: "HTTP proxy"
   color: "ffc7ea"
   description: ""

.github/workflows/ci-skip.yml

@@ -14,8 +14,6 @@ on:
       - go.mod
       - go.sum
   pull_request:
-    branches:
-      - master
     paths-ignore:
       - .github/workflows/ci.yml
       - cmd/**

.github/workflows/ci.yml

@@ -17,8 +17,6 @@ on:
       - go.mod
       - go.sum
   pull_request:
-    branches:
-      - master
     paths:
       - .github/workflows/ci.yml
       - cmd/**
@@ -39,16 +37,22 @@ jobs:
     env:
       DOCKER_BUILDKIT: "1"
     steps:
-      - uses: actions/checkout@v3
+      - uses: actions/checkout@v4
 
       - uses: reviewdog/action-misspell@v1
         with:
           locale: "US"
           level: error
+          exclude: |
+            ./internal/storage/servers.json
+            *.md
 
       - name: Linting
         run: docker build --target lint .
 
+      - name: Mocks check
+        run: docker build --target mocks .
+
       - name: Build test image
         run: docker build --target test -t test-container .
 
@@ -69,12 +73,12 @@ jobs:
       contents: read
       security-events: write
     steps:
-      - uses: actions/checkout@v3
-      - uses: github/codeql-action/init@v2
+      - uses: actions/checkout@v4
+      - uses: github/codeql-action/init@v3
         with:
           languages: go
-      - uses: github/codeql-action/autobuild@v2
-      - uses: github/codeql-action/analyze@v2
+      - uses: github/codeql-action/autobuild@v3
+      - uses: github/codeql-action/analyze@v3
 
   publish:
     if: |
@@ -88,19 +92,21 @@ jobs:
     permissions:
       actions: read
       contents: read
+      packages: write
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v3
+      - uses: actions/checkout@v4
 
       # extract metadata (tags, labels) for Docker
       # https://github.com/docker/metadata-action
       - name: Extract Docker metadata
         id: meta
-        uses: docker/metadata-action@v4
+        uses: docker/metadata-action@v5
         with:
           flavor: |
             latest=${{ github.ref == format('refs/heads/{0}', github.event.repository.default_branch) }}
           images: |
+            ghcr.io/qdm12/gluetun
             qmcgaw/gluetun
             qmcgaw/private-internet-access
           tags: |
@@ -110,20 +116,26 @@ jobs:
             type=semver,pattern=v{{major}},enable=${{ !startsWith(github.ref, 'refs/tags/v0.') }}
             type=raw,value=latest,enable=${{ github.ref == format('refs/heads/{0}', github.event.repository.default_branch) }}
 
-      - uses: docker/setup-qemu-action@v2
-      - uses: docker/setup-buildx-action@v2
+      - uses: docker/setup-qemu-action@v3
+      - uses: docker/setup-buildx-action@v3
 
-      - uses: docker/login-action@v2
+      - uses: docker/login-action@v3
         with:
           username: qmcgaw
           password: ${{ secrets.DOCKERHUB_PASSWORD }}
 
+      - uses: docker/login-action@v3
+        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@v3.0.0
+        uses: docker/build-push-action@v5
         with:
           platforms: linux/amd64,linux/386,linux/arm64,linux/arm/v6,linux/arm/v7,linux/ppc64le
           labels: ${{ steps.meta.outputs.labels }}

.github/workflows/closed-issue.yml

@@ -0,0 +1,21 @@
+name: Closed issue
+on:
+  issues:
+    types: [closed]
+
+jobs:
+  comment:
+    permissions:
+      issues: write
+    runs-on: ubuntu-latest
+    steps:
+      - uses: peter-evans/create-or-update-comment@v4
+        with:
+          token: ${{ github.token }}
+          issue-number: ${{ github.event.issue.number }}
+          body: |
+            Closed issues are **NOT** monitored, so commenting here is likely to be not seen.
+            If you think this is *still unresolved* and have **more information** to bring, please create another issue.
+
+            This is an automated comment setup because @qdm12 is the sole maintainer of this project
+            which became too popular to monitor issues closed.

.github/workflows/dockerhub-description.yml

@@ -1,25 +0,0 @@
-name: Docker Hub description
-on:
-  push:
-    branches:
-      - master
-    paths:
-      - README.md
-      - .github/workflows/dockerhub-description.yml
-jobs:
-  docker-hub-description:
-    if: github.repository == 'qdm12/gluetun'
-    runs-on: ubuntu-latest
-    permissions:
-      actions: read
-      contents: read
-    steps:
-      - uses: actions/checkout@v3
-
-      - uses: peter-evans/dockerhub-description@v3
-        with:
-          username: qmcgaw
-          password: ${{ secrets.DOCKERHUB_PASSWORD }}
-          repository: qmcgaw/gluetun
-          short-description: Lightweight Swiss-knife VPN client to connect to several VPN providers
-          readme-filepath: README.md

.github/workflows/labels.yml

@@ -7,9 +7,11 @@ on:
       - .github/workflows/labels.yml
 jobs:
   labeler:
+    permissions:
+      issues: write
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v3
-      - uses: crazy-max/ghaction-github-labeler@v4
+      - uses: actions/checkout@v4
+      - uses: crazy-max/ghaction-github-labeler@v5
         with:
           yaml-file: .github/labels.yml

.github/workflows/markdown-skip.yml

@@ -0,0 +1,21 @@
+name: Markdown
+on:
+  push:
+    branches:
+      - master
+    paths-ignore:
+      - "**.md"
+      - .github/workflows/markdown.yml
+  pull_request:
+    paths-ignore:
+      - "**.md"
+      - .github/workflows/markdown.yml
+
+jobs:
+  markdown:
+    runs-on: ubuntu-latest
+    permissions:
+      actions: read
+    steps:
+      - name: No trigger path triggered for required markdown workflow.
+        run: exit 0

.github/workflows/markdown.yml

@@ -0,0 +1,46 @@
+name: Markdown
+on:
+  push:
+    branches:
+      - master
+    paths:
+      - "**.md"
+      - .github/workflows/markdown.yml
+  pull_request:
+    paths:
+      - "**.md"
+      - .github/workflows/markdown.yml
+
+jobs:
+  markdown:
+    runs-on: ubuntu-latest
+    permissions:
+      actions: read
+      contents: read
+    steps:
+      - uses: actions/checkout@v4
+
+      - uses: DavidAnson/markdownlint-cli2-action@v14
+        with:
+          globs: "**.md"
+          config: .markdownlint.json
+
+      - uses: reviewdog/action-misspell@v1
+        with:
+          locale: "US"
+          level: error
+          pattern: |
+            *.md
+
+      - uses: gaurav-nelson/github-action-markdown-link-check@v1
+        with:
+          use-quiet-mode: yes
+
+      - uses: peter-evans/dockerhub-description@v3
+        if: github.repository == 'qdm12/gluetun' && github.event_name == 'push'
+        with:
+          username: qmcgaw
+          password: ${{ secrets.DOCKERHUB_PASSWORD }}
+          repository: qmcgaw/gluetun
+          short-description: Lightweight Swiss-knife VPN client to connect to several VPN providers
+          readme-filepath: README.md

.github/workflows/opened-issue.yml

@@ -0,0 +1,22 @@
+name: Opened issue
+on:
+  issues:
+    types: [opened]
+
+jobs:
+  comment:
+    permissions:
+      issues: write
+    runs-on: ubuntu-latest
+    steps:
+      - uses: peter-evans/create-or-update-comment@v4
+        with:
+          token: ${{ github.token }}
+          issue-number: ${{ github.event.issue.number }}
+          body: |
+            @qdm12 is more or less the only maintainer of this project and works on it in his free time.
+            Please:
+            - **do not** ask for updates, be patient
+            - :+1: the issue to show your support instead of commenting
+            @qdm12 usually checks issues at least once a week, if this is a new urgent bug,
+            [revert to an older tagged container image](https://github.com/qdm12/gluetun-wiki/blob/main/setup/docker-image-tags.md)

.golangci.yml

@@ -9,6 +9,8 @@ issues:
         - dupl
         - goerr113
         - containedctx
+        - goconst
+        - maintidx
     - path: "internal\\/server\\/.+\\.go"
       linters:
         - dupl
@@ -19,7 +21,6 @@ issues:
       source: "^.+= os\\.OpenFile\\(.+, .+, 0[0-9]{3}\\)"
       linters:
         - gomnd
-
     - text: "^mnd: Magic number: 0[0-9]{3}, in <argument> detected$"
       source: "^.+= os\\.MkdirAll\\(.+, 0[0-9]{3}\\)"
       linters:
@@ -30,13 +31,28 @@ issues:
     - text: "returns interface \\(github\\.com\\/vishvananda\\/netlink\\.Link\\)"
       linters:
         - ireturn
+    - path: "internal\\/openvpn\\/pkcs8\\/descbc\\.go"
+      text: "newCipherDESCBCBlock returns interface \\(github\\.com\\/youmark\\/pkcs8\\.Cipher\\)"
+      linters:
+        - ireturn
+    - path: "internal\\/firewall\\/.*\\.go"
+      text: "string `-i ` has [1-9][0-9]* occurrences, make it a constant"
+      linters:
+        - goconst
+    - path: "internal\\/provider\\/ipvanish\\/updater\\/servers.go"
+      text: "string ` in ` has 3 occurrences, make it a constant"
+      linters:
+        - goconst
+    - path: "internal\\/vpn\\/portforward.go"
+      text: 'directive `//nolint:ireturn` is unused for linter "ireturn"'
+      linters:
+        - nolintlint
 
 linters:
   enable:
     # - cyclop
     # - errorlint
-    # - varnamelen
-    # - wrapcheck
+    - asasalint
     - asciicheck
     - bidichk
     - bodyclose
@@ -44,6 +60,7 @@ linters:
     - decorder
     - dogsled
     - dupl
+    - dupword
     - durationcheck
     - errchkjson
     - errname
@@ -52,6 +69,7 @@ linters:
     - exportloopref
     - forcetypeassert
     - gci
+    - gocheckcompilerdirectives
     - gochecknoglobals
     - gochecknoinits
     - gocognit
@@ -66,14 +84,17 @@ linters:
     - gomoddirectives
     - goprintffuncname
     - gosec
+    - gosmopolitan
     - grouper
-    - ifshort
     - importas
+    - interfacebloat
     - ireturn
     - lll
     - maintidx
     - makezero
+    - mirror
     - misspell
+    - musttag
     - nakedret
     - nestif
     - nilerr
@@ -81,20 +102,24 @@ linters:
     - noctx
     - nolintlint
     - nosprintfhostport
+    - paralleltest
     - prealloc
     - predeclared
-    - predeclared
     - promlinter
+    - reassign
     - revive
     - rowserrcheck
     - sqlclosecheck
+    - tagalign
     - tenv
     - thelper
     - tparallel
     - unconvert
     - unparam
+    - usestdlibvars
     - wastedassign
     - whitespace
+    - zerologlint
 
 run:
   skip-dirs:

.markdownlint.json

@@ -0,0 +1,3 @@
+{
+  "MD013": false
+}

.vscode/extensions.json

@@ -0,0 +1,8 @@
+{
+  // This list should be kept to the strict minimum
+  // to develop this project.
+  "recommendations": [
+    "golang.go",
+    "davidanson.vscode-markdownlint",
+  ],
+}

.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"
+        },
     ]
 }

.vscode/settings.json

@@ -0,0 +1,29 @@
+{
+  // The settings should be kept to the strict minimum
+  // to develop this project.
+  "files.eol": "\n",
+  "editor.formatOnSave": true,
+  "go.buildTags": "linux",
+  "go.toolsEnvVars": {
+    "CGO_ENABLED": "0"
+  },
+  "go.testEnvVars": {
+    "CGO_ENABLED": "1"
+  },
+  "go.testFlags": [
+    "-v",
+    "-race"
+  ],
+  "go.testTimeout": "10s",
+  "go.coverOnSingleTest": true,
+  "go.coverOnSingleTestFile": true,
+  "go.coverOnTestPackage": true,
+  "go.useLanguageServer": true,
+  "[go]": {
+    "editor.codeActionsOnSave": {
+      "source.organizeImports": true
+    }
+  },
+  "go.lintTool": "golangci-lint",
+  "go.lintOnSave": "package"
+}

Dockerfile

@@ -1,18 +1,22 @@
-ARG ALPINE_VERSION=3.16
-ARG GO_ALPINE_VERSION=3.16
-ARG GO_VERSION=1.17
+ARG ALPINE_VERSION=3.18
+ARG GO_ALPINE_VERSION=3.18
+ARG GO_VERSION=1.21
 ARG XCPUTRANSLATE_VERSION=v0.6.0
-ARG GOLANGCI_LINT_VERSION=v1.46.2
+ARG GOLANGCI_LINT_VERSION=v1.56.2
+ARG MOCKGEN_VERSION=v1.6.0
 ARG BUILDPLATFORM=linux/amd64
 
 FROM --platform=${BUILDPLATFORM} qmcgaw/xcputranslate:${XCPUTRANSLATE_VERSION} AS xcputranslate
 FROM --platform=${BUILDPLATFORM} qmcgaw/binpot:golangci-lint-${GOLANGCI_LINT_VERSION} AS golangci-lint
+FROM --platform=${BUILDPLATFORM} qmcgaw/binpot:mockgen-${MOCKGEN_VERSION} AS mockgen
 
 FROM --platform=${BUILDPLATFORM} golang:${GO_VERSION}-alpine${GO_ALPINE_VERSION} AS base
 COPY --from=xcputranslate /xcputranslate /usr/local/bin/xcputranslate
-RUN apk --update add git g++
+# Note: findutils needed to have xargs support `-d` flag for mocks stage.
+RUN apk --update add git g++ findutils
 ENV CGO_ENABLED=0
 COPY --from=golangci-lint /bin /go/bin/golangci-lint
+COPY --from=mockgen /bin /go/bin/mockgen
 WORKDIR /tmp/gobuild
 COPY go.mod go.sum ./
 RUN go mod download
@@ -30,6 +34,18 @@ FROM --platform=${BUILDPLATFORM} base AS lint
 COPY .golangci.yml ./
 RUN golangci-lint run --timeout=10m
 
+FROM --platform=${BUILDPLATFORM} base AS mocks
+RUN git init && \
+    git config user.email ci@localhost && \
+    git config user.name ci && \
+    git config core.fileMode false && \
+    git add -A && \
+    git commit -m "snapshot" && \
+    grep -lr -E '^// Code generated by MockGen\. DO NOT EDIT\.$' . | xargs -r -d '\n' rm && \
+    go generate -run "mockgen" ./... && \
+    git diff --exit-code && \
+    rm -rf .git/
+
 FROM --platform=${BUILDPLATFORM} base AS build
 ARG TARGETPLATFORM
 ARG VERSION=unknown
@@ -74,29 +90,45 @@ ENV VPN_SERVICE_PROVIDER=pia \
     OPENVPN_FLAGS= \
     OPENVPN_CIPHERS= \
     OPENVPN_AUTH= \
-    OPENVPN_PROCESS_USER= \
-    OPENVPN_IPV6=off \
+    OPENVPN_PROCESS_USER=root \
     OPENVPN_CUSTOM_CONFIG= \
     # Wireguard
+    WIREGUARD_CONF_SECRETFILE=/run/secrets/wg0.conf \
     WIREGUARD_PRIVATE_KEY= \
+    WIREGUARD_PRIVATE_KEY_SECRETFILE=/run/secrets/wireguard_private_key \
     WIREGUARD_PRESHARED_KEY= \
+    WIREGUARD_PRESHARED_KEY_SECRETFILE=/run/secrets/wireguard_preshared_key \
     WIREGUARD_PUBLIC_KEY= \
+    WIREGUARD_ALLOWED_IPS= \
     WIREGUARD_ADDRESSES= \
+    WIREGUARD_ADDRESSES_SECRETFILE=/run/secrets/wireguard_addresses \
+    WIREGUARD_MTU=1400 \
+    WIREGUARD_IMPLEMENTATION=auto \
     # VPN server filtering
     SERVER_REGIONS= \
     SERVER_COUNTRIES= \
     SERVER_CITIES= \
     SERVER_HOSTNAMES= \
+    SERVER_CATEGORIES= \
     # # Mullvad only:
     ISP= \
     OWNED_ONLY=no \
     # # Private Internet Access only:
     PRIVATE_INTERNET_ACCESS_OPENVPN_ENCRYPTION_PRESET= \
-    PRIVATE_INTERNET_ACCESS_VPN_PORT_FORWARDING=off \
-    PRIVATE_INTERNET_ACCESS_VPN_PORT_FORWARDING_STATUS_FILE="/tmp/gluetun/forwarded_port" \
+    VPN_PORT_FORWARDING=off \
+    VPN_PORT_FORWARDING_LISTENING_PORT=0 \
+    VPN_PORT_FORWARDING_PROVIDER= \
+    VPN_PORT_FORWARDING_STATUS_FILE="/tmp/gluetun/forwarded_port" \
     # # Cyberghost only:
+    OPENVPN_CERT= \
+    OPENVPN_KEY= \
     OPENVPN_CLIENTCRT_SECRETFILE=/run/secrets/openvpn_clientcrt \
     OPENVPN_CLIENTKEY_SECRETFILE=/run/secrets/openvpn_clientkey \
+    # # VPNSecure only:
+    OPENVPN_ENCRYPTED_KEY= \
+    OPENVPN_ENCRYPTED_KEY_SECRETFILE=/run/secrets/openvpn_encrypted_key \
+    OPENVPN_KEY_PASSPHRASE= \
+    OPENVPN_KEY_PASSPHRASE_SECRETFILE=/run/secrets/openvpn_key_passphrase \
     # # Nordvpn only:
     SERVER_NUMBER= \
     # # PIA only:
@@ -105,6 +137,10 @@ ENV VPN_SERVICE_PROVIDER=pia \
     FREE_ONLY= \
     # # Surfshark only:
     MULTIHOP_ONLY= \
+    # # VPN Secure only:
+    PREMIUM_ONLY= \
+    # # PIA only:
+    PORT_FORWARD_ONLY= \
     # Firewall
     FIREWALL=on \
     FIREWALL_VPN_INPUT_PORTS= \
@@ -116,6 +152,7 @@ ENV VPN_SERVICE_PROVIDER=pia \
     # Health
     HEALTH_SERVER_ADDRESS=127.0.0.1:9999 \
     HEALTH_TARGET_ADDRESS=cloudflare.com:443 \
+    HEALTH_SUCCESS_WAIT_DURATION=5s \
     HEALTH_VPN_DURATION_INITIAL=6s \
     HEALTH_VPN_DURATION_ADDITION=5s \
     # DNS over TLS
@@ -138,6 +175,7 @@ ENV VPN_SERVICE_PROVIDER=pia \
     HTTPPROXY= \
     HTTPPROXY_LOG=off \
     HTTPPROXY_LISTENING_ADDRESS=":8888" \
+    HTTPPROXY_STEALTH=off \
     HTTPPROXY_USER= \
     HTTPPROXY_PASSWORD= \
     HTTPPROXY_USER_SECRETFILE=/run/secrets/httpproxy_user \
@@ -150,6 +188,7 @@ ENV VPN_SERVICE_PROVIDER=pia \
     SHADOWSOCKS_PASSWORD_SECRETFILE=/run/secrets/shadowsocks_password \
     SHADOWSOCKS_CIPHER=chacha20-ietf-poly1305 \
     # Control server
+    HTTP_CONTROL_SERVER_LOG=on \
     HTTP_CONTROL_SERVER_ADDRESS=":8000" \
     # Server data updater
     UPDATER_PERIOD=0 \
@@ -158,6 +197,8 @@ ENV VPN_SERVICE_PROVIDER=pia \
     # Public IP
     PUBLICIP_FILE="/tmp/gluetun/ip" \
     PUBLICIP_PERIOD=12h \
+    PUBLICIP_API=ipinfo \
+    PUBLICIP_API_TOKEN= \
     # Pprof
     PPROF_ENABLED=no \
     PPROF_BLOCK_PROFILE_RATE=0 \
@@ -172,12 +213,12 @@ 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 && \
-    apk add --no-cache --update -X "https://dl-cdn.alpinelinux.org/alpine/v3.12/main" openvpn==2.4.12-r0 && \
-    mv /usr/sbin/openvpn /usr/sbin/openvpn2.4 && \
+RUN apk add --no-cache --update -l wget && \
+    apk add --no-cache --update -X "https://dl-cdn.alpinelinux.org/alpine/v3.17/main" openvpn\~2.5 && \
+    mv /usr/sbin/openvpn /usr/sbin/openvpn2.5 && \
     apk del openvpn && \
     apk add --no-cache --update openvpn ca-certificates iptables ip6tables unbound tzdata && \
-    mv /usr/sbin/openvpn /usr/sbin/openvpn2.5 && \
+    mv /usr/sbin/openvpn /usr/sbin/openvpn2.6 && \
     # Fix vulnerability issue
     apk add --no-cache --update busybox && \
     rm -rf /var/cache/apk/* /etc/unbound/* /usr/sbin/unbound-* /etc/openvpn/*.sh /usr/lib/openvpn/plugins/openvpn-plugin-down-root.so && \

README.md

@@ -1,125 +1,130 @@
-# Gluetun VPN client
-
-Lightweight swiss-knife-like VPN client to multiple VPN sercice 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**,  **Surfshark**, **TorGuard**, **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 [common errors](https://github.com/qdm12/gluetun-wiki/tree/main/errors) and [faq](https://github.com/qdm12/gluetun-wiki/tree/main/faq)
+  - [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)
+- 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 [the development page](https://github.com/qdm12/gluetun-wiki/blob/main/contributing/development.md) and [add a provider page](https://github.com/qdm12/gluetun-wiki/blob/main/contributing/add-a-provider.md)
+- 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 3.18 for a small Docker image of 35.6MB
+- 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 **AirVPN**, **Ivpn**, **Mullvad**, **NordVPN**, **Surfshark** and **Windscribe**
+  - For **ProtonVPN**, **PureVPN**, **Torguard**, **VPN Unlimited** and **WeVPN** using [the custom provider](https://github.com/qdm12/gluetun-wiki/blob/main/setup/providers/custom.md)
+  - For custom Wireguard configurations using [the custom provider](https://github.com/qdm12/gluetun-wiki/blob/main/setup/providers/custom.md)
+  - 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/blob/main/setup/connect-a-container-to-gluetun.md)
+- [Connect LAN devices to it](https://github.com/qdm12/gluetun-wiki/blob/main/setup/connect-a-lan-device-to-gluetun.md)
+- 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/blob/main/setup/providers/private-internet-access.md#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-wiki/issues/new)
+
+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/blob/main/setup/connect-a-container-to-gluetun.md#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/tree/main/setup#setup
+      - 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/blob/main/setup/servers.md#update-the-vpn-servers-list
+      - UPDATER_PERIOD=
+```
+
+🆕 Image also available as `ghcr.io/qdm12/gluetun`
+
+## License
+
+[![MIT](https://img.shields.io/github/license/qdm12/gluetun)](https://github.com/qdm12/gluetun/blob/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"
@@ -34,7 +34,7 @@ import (
 	"github.com/qdm12/gluetun/internal/pprof"
 	"github.com/qdm12/gluetun/internal/provider"
 	"github.com/qdm12/gluetun/internal/publicip"
-	"github.com/qdm12/gluetun/internal/publicip/ipinfo"
+	pubipapi "github.com/qdm12/gluetun/internal/publicip/api"
 	"github.com/qdm12/gluetun/internal/routing"
 	"github.com/qdm12/gluetun/internal/server"
 	"github.com/qdm12/gluetun/internal/shadowsocks"
@@ -77,26 +77,28 @@ 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()
 
-	envReader := env.New(logger)
-	filesReader := files.New()
 	secretsReader := secrets.New()
-	muxReader := mux.New(envReader, filesReader, secretsReader)
+	filesReader := files.New()
+	envReader := env.New(logger)
+	muxReader := mux.New(secretsReader, filesReader, envReader)
 
 	errorCh := make(chan error)
 	go func() {
 		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":
@@ -148,7 +159,7 @@ func _main(ctx context.Context, buildInfo models.BuildInformation,
 		}
 	}
 
-	announcementExp, err := time.Parse(time.RFC3339, "2021-02-15T00:00:00Z")
+	announcementExp, err := time.Parse(time.RFC3339, "2023-07-01T00:00:00Z")
 	if err != nil {
 		return err
 	}
@@ -159,7 +170,7 @@ func _main(ctx context.Context, buildInfo models.BuildInformation,
 		Version:      buildInfo.Version,
 		Commit:       buildInfo.Commit,
 		BuildDate:    buildInfo.Created,
-		Announcement: "Large settings parsing refactoring merged on 2022-01-06, please report any issue!",
+		Announcement: "Wiki moved to https://github.com/qdm12/gluetun-wiki",
 		AnnounceExp:  announcementExp,
 		// Sponsor information
 		PaypalUser:    "qmcgaw",
@@ -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)
@@ -247,8 +264,8 @@ func _main(ctx context.Context, buildInfo models.BuildInformation,
 
 	err = printVersions(ctx, logger, []printVersionElement{
 		{name: "Alpine", getVersion: alpineConf.Version},
-		{name: "OpenVPN 2.4", getVersion: ovpnConf.Version24},
 		{name: "OpenVPN 2.5", getVersion: ovpnConf.Version25},
+		{name: "OpenVPN 2.6", getVersion: ovpnConf.Version26},
 		{name: "Unbound", getVersion: dnsConf.Version},
 		{name: "IPtables", getVersion: func(ctx context.Context) (version string, err error) {
 			return firewall.Version(ctx, cmder)
@@ -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...")
@@ -304,6 +325,11 @@ func _main(ctx context.Context, buildInfo models.BuildInformation,
 		return err
 	}
 
+	err = routingConf.AddLocalRules(localNetworks)
+	if err != nil {
+		return fmt.Errorf("adding local rules: %w", err)
+	}
+
 	const tunDevice = "/dev/net/tun"
 	if err := tun.Check(tunDevice); err != nil {
 		logger.Info(err.Error() + "; creating it...")
@@ -339,20 +365,24 @@ 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,
-		httpClient, firewallConf, portForwardLogger, puid, pgid)
-	portForwardHandler, portForwardCtx, portForwardDone := goshutdown.NewGoRoutineHandler(
-		"port forwarding", goroutine.OptionTimeout(time.Second))
-	go portForwardLooper.Run(portForwardCtx, portForwardDone)
+		routingConf, httpClient, firewallConf, portForwardLogger, puid, pgid)
+	portForwardRunError, err := portForwardLooper.Start(ctx)
+	if err != nil {
+		return fmt.Errorf("starting port forwarding loop: %w", err)
+	}
 
-	unboundLogger := logger.New(log.SetComponent("dns over tls"))
+	unboundLogger := logger.New(log.SetComponent("dns"))
 	unboundLooper := dns.NewLoop(dnsConf, allSettings.DNS, httpClient,
 		unboundLogger)
 	dnsHandler, dnsCtx, dnsDone := goshutdown.NewGoRoutineHandler(
@@ -366,19 +396,18 @@ func _main(ctx context.Context, buildInfo models.BuildInformation,
 	go unboundLooper.RunRestartTicker(dnsTickerCtx, dnsTickerDone)
 	controlGroupHandler.Add(dnsTickerHandler)
 
-	ipFetcher := ipinfo.New(httpClient)
+	publicipAPI, _ := pubipapi.ParseProvider(allSettings.PublicIP.API)
+	ipFetcher, err := pubipapi.New(publicipAPI, httpClient, *allSettings.PublicIP.APIToken)
+	if err != nil {
+		return fmt.Errorf("creating public IP API client: %w", err)
+	}
 	publicIPLooper := publicip.NewLoop(ipFetcher,
 		logger.New(log.SetComponent("ip getter")),
 		allSettings.PublicIP, puid, pgid)
-	pubIPHandler, pubIPCtx, pubIPDone := goshutdown.NewGoRoutineHandler(
-		"public IP", goroutine.OptionTimeout(defaultShutdownTimeout))
-	go publicIPLooper.Run(pubIPCtx, pubIPDone)
-	otherGroupHandler.Add(pubIPHandler)
-
-	pubIPTickerHandler, pubIPTickerCtx, pubIPTickerDone := goshutdown.NewGoRoutineHandler(
-		"public IP", goroutine.OptionTimeout(defaultShutdownTimeout))
-	go publicIPLooper.RunRestartTicker(pubIPTickerCtx, pubIPTickerDone)
-	tickersGroupHandler.Add(pubIPTickerHandler)
+	publicIPRunError, err := publicIPLooper.Start(ctx)
+	if err != nil {
+		return fmt.Errorf("starting public ip loop: %w", err)
+	}
 
 	updaterLogger := logger.New(log.SetComponent("updater"))
 
@@ -389,7 +418,7 @@ 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 +460,10 @@ 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)
+		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)
@@ -451,13 +481,31 @@ func _main(ctx context.Context, buildInfo models.BuildInformation,
 		order.OptionOnSuccess(defaultShutdownOnSuccess),
 		order.OptionOnFailure(defaultShutdownOnFailure))
 	orderHandler.Append(controlGroupHandler, tickersGroupHandler, healthServerHandler,
-		vpnHandler, portForwardHandler, otherGroupHandler)
+		vpnHandler, otherGroupHandler)
 
 	// Start VPN for the first time in a blocking call
 	// until the VPN is launched
 	_, _ = vpnLooper.ApplyStatus(ctx, constants.Running) // TODO option to disable with variable
 
-	<-ctx.Done()
+	select {
+	case <-ctx.Done():
+		stoppers := []interface {
+			String() string
+			Stop() error
+		}{
+			portForwardLooper, publicIPLooper,
+		}
+		for _, stopper := range stoppers {
+			err := stopper.Stop()
+			if err != nil {
+				logger.Error(fmt.Sprintf("stopping %s: %s", stopper, err))
+			}
+		}
+	case err := <-portForwardRunError:
+		logger.Errorf("port forwarding loop crashed: %s", err)
+	case err := <-publicIPRunError:
+		logger.Errorf("public IP loop crashed: %s", err)
+	}
 
 	return orderHandler.Shutdown(context.Background())
 }
@@ -480,7 +528,7 @@ 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)
 	}
@@ -489,32 +537,49 @@ func printVersions(ctx context.Context, logger infoer,
 }
 
 type netLinker interface {
+	Addresser
+	Router
+	Ruler
+	Linker
+	IsWireguardSupported() (ok bool, err error)
+	IsIPv6Supported() (ok bool, err error)
+	PatchLoggerLevel(level log.Level)
+}
+
+type Addresser interface {
 	AddrList(link netlink.Link, family int) (
 		addresses []netlink.Addr, err error)
-	AddrAdd(link netlink.Link, addr *netlink.Addr) error
-	IsWireguardSupported() (ok bool, err error)
-	RouteList(link netlink.Link, family int) (
-		routes []netlink.Route, err error)
-	RouteAdd(route *netlink.Route) error
-	RouteDel(route *netlink.Route) error
-	RouteReplace(route *netlink.Route) error
+	AddrReplace(link netlink.Link, addr netlink.Addr) error
+}
+
+type Router interface {
+	RouteList(family int) (routes []netlink.Route, err error)
+	RouteAdd(route netlink.Route) error
+	RouteDel(route netlink.Route) error
+	RouteReplace(route netlink.Route) error
+}
+
+type Ruler interface {
 	RuleList(family int) (rules []netlink.Rule, err error)
-	RuleAdd(rule *netlink.Rule) error
-	RuleDel(rule *netlink.Rule) error
+	RuleAdd(rule netlink.Rule) error
+	RuleDel(rule netlink.Rule) error
+}
+
+type Linker interface {
 	LinkList() (links []netlink.Link, err error)
 	LinkByName(name string) (link netlink.Link, err error)
 	LinkByIndex(index int) (link netlink.Link, err error)
-	LinkAdd(link netlink.Link) (err error)
+	LinkAdd(link netlink.Link) (linkIndex int, err error)
 	LinkDel(link netlink.Link) (err error)
-	LinkSetUp(link netlink.Link) (err error)
+	LinkSetUp(link netlink.Link) (linkIndex int, err error)
 	LinkSetDown(link netlink.Link) (err error)
 }
 
 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
 }
 
@@ -522,3 +587,9 @@ 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

@@ -1,45 +1,55 @@
 module github.com/qdm12/gluetun
 
-go 1.17
+go 1.21
 
 require (
-	github.com/breml/rootcerts v0.2.3
-	github.com/fatih/color v1.13.0
+	github.com/breml/rootcerts v0.2.16
+	github.com/fatih/color v1.16.0
 	github.com/golang/mock v1.6.0
+	github.com/klauspost/compress v1.17.4
+	github.com/klauspost/pgzip v1.2.6
 	github.com/qdm12/dns v1.11.0
 	github.com/qdm12/golibs v0.0.0-20210822203818-5c568b0777b6
+	github.com/qdm12/gosettings v0.4.0-rc1
 	github.com/qdm12/goshutdown v0.3.0
 	github.com/qdm12/gosplash v0.1.0
 	github.com/qdm12/gotree v0.2.0
-	github.com/qdm12/govalid v0.1.0
+	github.com/qdm12/govalid v0.2.0-rc1
 	github.com/qdm12/log v0.1.0
-	github.com/qdm12/ss-server v0.4.0
+	github.com/qdm12/ss-server v0.5.0
 	github.com/qdm12/updated v0.0.0-20210603204757-205acfe6937e
-	github.com/stretchr/testify v1.7.2
-	github.com/vishvananda/netlink v1.1.1-0.20211129163951-9ada19101fc5
-	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
-	inet.af/netaddr v0.0.0-20210718074554-06ca8145d722
+	github.com/stretchr/testify v1.8.4
+	github.com/ulikunitz/xz v0.5.11
+	github.com/vishvananda/netlink v1.2.1-beta.2
+	github.com/youmark/pkcs8 v0.0.0-20201027041543-1326539a0a0a
+	golang.org/x/net v0.19.0
+	golang.org/x/sys v0.15.0
+	golang.org/x/text v0.14.0
+	golang.zx2c4.com/wireguard v0.0.0-20230325221338-052af4a8072b
+	golang.zx2c4.com/wireguard/wgctrl v0.0.0-20230215201556-9c5414ab4bde
+	gopkg.in/ini.v1 v1.67.0
+	inet.af/netaddr v0.0.0-20220811202034-502d2d690317
 )
 
 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 v0.5.9 // indirect
+	github.com/josharian/native v1.0.0 // indirect
+	github.com/mattn/go-colorable v0.1.13 // indirect
+	github.com/mattn/go-isatty v0.0.20 // indirect
+	github.com/mdlayher/genetlink v1.2.0 // indirect
+	github.com/mdlayher/netlink v1.6.2 // 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
-	golang.org/x/net v0.0.0-20210504132125-bbd867fde50d // indirect
+	go4.org/intern v0.0.0-20211027215823-ae77deb06f29 // indirect
+	go4.org/unsafe/assume-no-moving-gc v0.0.0-20230525183740-e7c30c78aeb2 // indirect
+	golang.org/x/crypto v0.17.0 // indirect
+	golang.org/x/exp v0.0.0-20230522175609-2e198f4a06a1 // indirect
+	golang.org/x/sync v0.1.0 // indirect
+	golang.zx2c4.com/wintun v0.0.0-20230126152724-0fa3db229ce2 // 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 v0.2.3 h1:1vkYjKOiHVSyuz9Ue4AOrViEvUm8gk8phTg0vbcuU0A=
-github.com/breml/rootcerts v0.2.3/go.mod h1:24FDtzYMpqIeYC7QzaE8VPRQaFZU5TIUDlyk8qwjD88=
+github.com/breml/rootcerts v0.2.16 h1:yN1TGvicfHx8dKz3OQRIrx/5nE/iN3XT1ibqGbd6urc=
+github.com/breml/rootcerts v0.2.16/go.mod h1:S/PKh+4d1HUn4HQovEB8hPJZO6pUZYrIhmXBhsegfXw=
 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 v1.16.0 h1:zmkK9Ngbjj+K0yRhTVONQh1p/HknKYSlNT+vZCzyokM=
+github.com/fatih/color v1.16.0/go.mod h1:fL2Sau1YI5c0pdGEVCbKQbLXB6edEj1ZgiY4NijnWvE=
 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=
@@ -36,29 +36,24 @@ 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/btree v1.0.1 h1:gK4Kx5IaGY9CD5sPJ36FHiBJ6ZXl0kilRiiCj+jdYp4=
+github.com/google/btree v1.0.1/go.mod h1:xXMiIv4Fb/0kKde4SpL7qlzvu5cMJDRkFDxJfI9uaxA=
 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/go.mod h1:n+brtR0CgQNWTVd5ZUFpTBC8YFBDLK/h/bpaJ8/DtOE=
+github.com/google/go-cmp v0.5.9 h1:O2Tfq5qg4qc4AmwVlvv0oLiVAGB7enBSJ2x2DqQFi38=
+github.com/google/go-cmp v0.5.9/go.mod h1:17dUlkBOakJ0+DkrSSNjCkIjxS6bF9zb3elmeNGIjoY=
 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=
-github.com/jsimonetti/rtnetlink v0.0.0-20210122163228-8d122574c736/go.mod h1:ZXpIyOK59ZnN7J0BV99cZUPmsqDRZ3eq5X+st7u/oSA=
-github.com/jsimonetti/rtnetlink v0.0.0-20210212075122-66c871082f2b h1:c3NTyLNozICy8B4mlMXemD3z/gXgQzVXZS/HqT+i3do=
-github.com/jsimonetti/rtnetlink v0.0.0-20210212075122-66c871082f2b/go.mod h1:8w9Rh8m+aHZIG69YPGGem1i5VzoyRC8nw2kA8B+ik5U=
+github.com/josharian/native v1.0.0 h1:Ts/E8zCSEsG17dUqv7joXJFybuMLjQfWE04tsBODTxk=
+github.com/josharian/native v1.0.0/go.mod h1:7X/raswPFr05uY3HiLlYeyQntB6OO7E/d2Cu7qoaN2w=
 github.com/kevinburke/ssh_config v0.0.0-20190725054713-01f96b0aa0cd/go.mod h1:CT57kijsi8u/K/BOFA39wgDQJ9CxiF4nAY/ojJ6r6mM=
+github.com/klauspost/compress v1.17.4 h1:Ej5ixsIri7BrIjBkRZLTo6ghwrEtHFk7ijlczPW4fZ4=
+github.com/klauspost/compress v1.17.4/go.mod h1:/dCuZOvVtNoHsyb+cuJD3itjs3NbnF6KH9zAO4BDxPM=
+github.com/klauspost/pgzip v1.2.6 h1:8RXeL5crjEUFnR2/Sn6GJNWtSQ3Dk8pq4CL3jvdDyjU=
+github.com/klauspost/pgzip v1.2.6/go.mod h1:Ch1tH69qFZu15pkjo5kYi6mth2Zzwzt50oCQKQE9RUs=
 github.com/kr/pretty v0.1.0 h1:L/CwN0zerZDmRFUapSPitk6f+Q3+0za1rQkzVuMiMFI=
 github.com/kr/pretty v0.1.0/go.mod h1:dAy3ld7l9f0ibDNOQOHHMYYIIbhfbHSm3C4ZsoJORNo=
 github.com/kr/pty v1.1.1/go.mod h1:pFQYn66WHrOpPYNljwOMqo10TkYh1fy3cYio2l3bCsQ=
@@ -68,25 +63,20 @@ github.com/kr/text v0.1.0/go.mod h1:4Jbv+DJW3UT/LiOwJeYQe1efqtUx/iVham/4vfdArNI=
 github.com/kyokomi/emoji v2.2.4+incompatible/go.mod h1:mZ6aGCD7yk8j6QY6KICwnZ2pxoszVseX1DNoGtU2tBA=
 github.com/mailru/easyjson v0.0.0-20180823135443-60711f1a8329/go.mod h1:C1wdFJiN94OJF2b5HbByQZoLdCWB1Yqtg26g4irojpc=
 github.com/mattn/go-colorable v0.1.8/go.mod h1:u6P/XSegPjTcexA+o6vUJrdnUu04hMope9wVRipJSqc=
-github.com/mattn/go-colorable v0.1.9 h1:sqDoxXbdeALODt0DAeJCVp38ps9ZogZEAXjus69YV3U=
-github.com/mattn/go-colorable v0.1.9/go.mod h1:u6P/XSegPjTcexA+o6vUJrdnUu04hMope9wVRipJSqc=
+github.com/mattn/go-colorable v0.1.13 h1:fFA4WZxdEF4tXPZVKMLwD8oUnCTTo08duU7wxecdEvA=
+github.com/mattn/go-colorable v0.1.13/go.mod h1:7S9/ev0klgBDR4GtXTXX8a3vIGJpMovkB8vQcUbaXHg=
 github.com/mattn/go-isatty v0.0.12/go.mod h1:cbi8OIDigv2wuxKPP5vlRcQ1OAZbq2CE4Kysco4FUpU=
-github.com/mattn/go-isatty v0.0.14 h1:yVuAays6BHfxijgZPzw+3Zlu5yQgKGP2/hcQbHb7S9Y=
-github.com/mattn/go-isatty v0.0.14/go.mod h1:7GGIvUiUoEMVVmxf/4nioHXj79iQHKdU27kJ6hsGG94=
-github.com/mdlayher/ethtool v0.0.0-20210210192532-2b88debcdd43 h1:WgyLFv10Ov49JAQI/ZLUkCZ7VJS3r74hwFIGXJsgZlY=
-github.com/mdlayher/ethtool v0.0.0-20210210192532-2b88debcdd43/go.mod h1:+t7E0lkKfbBsebllff1xdTmyJt8lH37niI6kwFk9OTo=
-github.com/mdlayher/genetlink v1.0.0 h1:OoHN1OdyEIkScEmRgxLEe2M9U8ClMytqA5niynLtfj0=
-github.com/mdlayher/genetlink v1.0.0/go.mod h1:0rJ0h4itni50A86M2kHcgS85ttZazNt7a8H2a2cw0Gc=
-github.com/mdlayher/netlink v0.0.0-20190409211403-11939a169225/go.mod h1:eQB3mZE4aiYnlUsyGGCOpPETfdQq4Jhsgf1fk3cwQaA=
-github.com/mdlayher/netlink v1.0.0/go.mod h1:KxeJAFOFLG6AjpyDkQ/iIhxygIUKD+vcwqcnu43w/+M=
-github.com/mdlayher/netlink v1.1.0/go.mod h1:H4WCitaheIsdF9yOYu8CFmCgQthAPIWZmcKp9uZHgmY=
-github.com/mdlayher/netlink v1.1.1/go.mod h1:WTYpFb/WTvlRJAyKhZL5/uy69TDDpHHu2VZmb2XgV7o=
-github.com/mdlayher/netlink v1.2.0/go.mod h1:kwVW1io0AZy9A1E2YYgaD4Cj+C+GPkU6klXCMzIJ9p8=
-github.com/mdlayher/netlink v1.2.1/go.mod h1:bacnNlfhqHqqLo4WsYeXSqfyXkInQ9JneWI68v1KwSU=
-github.com/mdlayher/netlink v1.2.2-0.20210123213345-5cc92139ae3e/go.mod h1:bacnNlfhqHqqLo4WsYeXSqfyXkInQ9JneWI68v1KwSU=
-github.com/mdlayher/netlink v1.3.0/go.mod h1:xK/BssKuwcRXHrtN04UBkwQ6dY9VviGGuriDdoPSWys=
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+golang.org/x/sync v0.0.0-20220923202941-7f9b1623fab7/go.mod h1:RxMgew5VJxzue5/jJTE5uejpjVlOe/izrB70Jof72aM=
+golang.org/x/sync v0.1.0 h1:wsuoTGHzEhffawBOhz5CYhcrV4IdKZbEyZjBMuTp12o=
+golang.org/x/sync v0.1.0/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 v0.0.0-20220319134239-a9b59b0215f8/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
+golang.org/x/sys v0.0.0-20220728004956-3c1f35247d10/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/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
+golang.org/x/sys v0.15.0 h1:h48lPFYpsTvQJZF4EKyI4aLHaev3CxivZmv7yZig9pc=
+golang.org/x/sys v0.15.0/go.mod h1:/VUhepiaJMQUp4+oa/7Zr1D23ma6VTLIYjOOTFZPUcA=
 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 v0.14.0 h1:ScX5w1eTa3QqT8oi6+ziP7dTV1S2+ALU0bI+0zXKWiQ=
+golang.org/x/text v0.14.0/go.mod h1:18ZOQIKpY8NJVqYksKHtTdi31H5itFRjB5/qKTNYzSU=
+golang.org/x/time v0.0.0-20191024005414-555d28b269f0 h1:/5xXl8Y5W96D+TtHSlonuFqGHIWVuyCkGJLwGh9JJFs=
+golang.org/x/time v0.0.0-20191024005414-555d28b269f0/go.mod h1:tRJNPiyCQ0inRvYxbN9jk5I+vvW/OXSQhTDSoE431IQ=
 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=
@@ -235,16 +226,18 @@ golang.org/x/tools v0.1.1/go.mod h1:o0xws9oXOQQZyjljx8fwUC0k7L1pTE6eaCbjGeHmOkk=
 golang.org/x/xerrors v0.0.0-20190717185122-a985d3407aa7/go.mod h1:I/5z698sn9Ka8TeJc9MKroUUfqBBauWjQqLJ2OPfmY0=
 golang.org/x/xerrors v0.0.0-20191011141410-1b5146add898/go.mod h1:I/5z698sn9Ka8TeJc9MKroUUfqBBauWjQqLJ2OPfmY0=
 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 v0.0.0-20230126152724-0fa3db229ce2 h1:B82qJJgjvYKsXS9jeunTOisW56dUokqW/FOteYJJ/yg=
+golang.zx2c4.com/wintun v0.0.0-20230126152724-0fa3db229ce2/go.mod h1:deeaetjYA+DHMHg+sMSMI58GrEteJUUzzw7en6TJQcI=
+golang.zx2c4.com/wireguard v0.0.0-20230325221338-052af4a8072b h1:J1CaxgLerRR5lgx3wnr6L04cJFbWoceSK9JWBdglINo=
+golang.zx2c4.com/wireguard v0.0.0-20230325221338-052af4a8072b/go.mod h1:tqur9LnfstdR9ep2LaJT4lFUl0EjlHtge+gAjmsHUG4=
+golang.zx2c4.com/wireguard/wgctrl v0.0.0-20230215201556-9c5414ab4bde h1:ybF7AMzIUikL9x4LgwEmzhXtzRpKNqngme1VGDWz+Nk=
+golang.zx2c4.com/wireguard/wgctrl v0.0.0-20230215201556-9c5414ab4bde/go.mod h1:mQqgjkW8GQQcJQsbBvK890TKqUK1DfKWkuBGbOkuMHQ=
 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=
+gopkg.in/ini.v1 v1.67.0 h1:Dgnx+6+nfE+IfzjUEISNeydPJh9AXNNsWbGP9KzCsOA=
+gopkg.in/ini.v1 v1.67.0/go.mod h1:pNLf8WUiyNEtQjuu5G5vTm06TEv9tsIgeAvK8hOrP4k=
 gopkg.in/src-d/go-billy.v4 v4.3.2/go.mod h1:nDjArDMp+XMs1aFAESLRjfGSgfvoYN0hDfzEk0GjC98=
 gopkg.in/src-d/go-git-fixtures.v3 v3.5.0/go.mod h1:dLBcvytrw/TYZsNTWCnkNF2DSIlzWYqTe3rJR56Ac7g=
 gopkg.in/src-d/go-git.v4 v4.13.1/go.mod h1:nx5NYcxdKxq5fpltdHnPa2Exj4Sx0EclMWZQbYDu2z8=
@@ -254,6 +247,8 @@ gopkg.in/yaml.v2 v2.2.2/go.mod h1:hI93XBmqTisBFMUTm0b8Fm+jr3Dg1NNxqwp+5A1VGuI=
 gopkg.in/yaml.v3 v3.0.0-20200313102051-9f266ea9e77c/go.mod h1:K4uyk7z7BCEPqu6E+C64Yfv1cQ7kz7rIZviUmN+EgEM=
 gopkg.in/yaml.v3 v3.0.1 h1:fxVm/GzAzEWqLHuvctI91KS9hhNmmWOoWu0XTYJS7CA=
 gopkg.in/yaml.v3 v3.0.1/go.mod h1:K4uyk7z7BCEPqu6E+C64Yfv1cQ7kz7rIZviUmN+EgEM=
+gvisor.dev/gvisor v0.0.0-20221203005347-703fd9b7fbc0 h1:Wobr37noukisGxpKo5jAsLREcpj61RxrWYzD8uwveOY=
+gvisor.dev/gvisor v0.0.0-20221203005347-703fd9b7fbc0/go.mod h1:Dn5idtptoW1dIos9U6A2rpebLs/MtTwFacjKb8jLdQA=
 inet.af/netaddr v0.0.0-20210511181906-37180328850c/go.mod h1:z0nx+Dh+7N7CC8V5ayHtHGpZpxLQZZxkIaaz6HN65Ls=
-inet.af/netaddr v0.0.0-20210718074554-06ca8145d722 h1:Qws2rZnQudC58cIagVucPQDLmMi3kAXgxscsgD0v6DU=
-inet.af/netaddr v0.0.0-20210718074554-06ca8145d722/go.mod h1:z0nx+Dh+7N7CC8V5ayHtHGpZpxLQZZxkIaaz6HN65Ls=
+inet.af/netaddr v0.0.0-20220811202034-502d2d690317 h1:U2fwK6P2EqmopP/hFLTOAjWTki0qgd4GMJn5X8wOleU=
+inet.af/netaddr v0.0.0-20220811202034-502d2d690317/go.mod h1:OIezDfdzOgFhuw4HuWapWq2e9l0H9tK4F1j+ETRtF3k=

internal/alpine/version.go

@@ -7,7 +7,7 @@ import (
 	"strings"
 )
 
-func (a *Alpine) Version(ctx context.Context) (version string, err error) {
+func (a *Alpine) Version(context.Context) (version string, err error) {
 	file, err := os.OpenFile(a.alpineReleasePath, os.O_RDONLY, 0)
 	if err != nil {
 		return "", err

internal/cli/ci.go

@@ -2,6 +2,6 @@ package cli
 
 import "context"
 
-func (c *CLI) CI(context context.Context) error {
+func (c *CLI) CI(context.Context) error {
 	return nil
 }

internal/cli/formatservers.go

@@ -33,15 +33,20 @@ func addProviderFlag(flagSet *flag.FlagSet, providerToFormat map[string]*bool,
 func (c *CLI) FormatServers(args []string) error {
 	var format, output string
 	allProviders := providers.All()
+	allProviderFlags := make([]string, len(allProviders))
+	for i, provider := range allProviders {
+		allProviderFlags[i] = strings.ReplaceAll(provider, " ", "-")
+	}
+
 	providersToFormat := make(map[string]*bool, len(allProviders))
-	for _, provider := range allProviders {
+	for _, provider := range allProviderFlags {
 		providersToFormat[provider] = new(bool)
 	}
-	flagSet := flag.NewFlagSet("markdown", flag.ExitOnError)
+	flagSet := flag.NewFlagSet("format-servers", flag.ExitOnError)
 	flagSet.StringVar(&format, "format", "markdown", "Format to use which can be: 'markdown'")
 	flagSet.StringVar(&output, "output", "/dev/stdout", "Output file to write the formatted data to")
 	titleCaser := cases.Title(language.English)
-	for _, provider := range allProviders {
+	for _, provider := range allProviderFlags {
 		addProviderFlag(flagSet, providersToFormat, provider, titleCaser)
 	}
 	if err := flagSet.Parse(args); err != nil {
@@ -61,19 +66,25 @@ func (c *CLI) FormatServers(args []string) error {
 	}
 	switch len(providers) {
 	case 0:
-		return ErrProviderUnspecified
+		return fmt.Errorf("%w", ErrProviderUnspecified)
 	case 1:
 	default:
 		return fmt.Errorf("%w: %d specified: %s",
 			ErrMultipleProvidersToFormat, len(providers),
 			strings.Join(providers, ", "))
 	}
-	providerToFormat := providers[0]
+
+	var providerToFormat string
+	for _, providerToFormat = range allProviders {
+		if strings.ReplaceAll(providerToFormat, " ", "-") == providers[0] {
+			break
+		}
+	}
 
 	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 +92,18 @@ 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) 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/nooplogger.go

@@ -8,9 +8,9 @@ func newNoopLogger() *noopLogger {
 	return new(noopLogger)
 }
 
-func (l *noopLogger) Debug(s string)                 {}
-func (l *noopLogger) Info(s string)                  {}
-func (l *noopLogger) Warn(s string)                  {}
-func (l *noopLogger) Error(s string)                 {}
-func (l *noopLogger) PatchLevel(level logging.Level) {}
-func (l *noopLogger) PatchPrefix(prefix string)      {}
+func (l *noopLogger) Debug(string)             {}
+func (l *noopLogger) Info(string)              {}
+func (l *noopLogger) Warn(string)              {}
+func (l *noopLogger) Error(string)             {}
+func (l *noopLogger) PatchLevel(logging.Level) {}
+func (l *noopLogger) PatchPrefix(string)       {}

internal/cli/openvpnconfig.go

@@ -3,16 +3,15 @@ package cli
 import (
 	"context"
 	"fmt"
-	"net"
 	"net/http"
+	"net/netip"
 	"strings"
 	"time"
 
-	"github.com/qdm12/gluetun/internal/configuration/sources"
 	"github.com/qdm12/gluetun/internal/constants"
+	"github.com/qdm12/gluetun/internal/models"
 	"github.com/qdm12/gluetun/internal/openvpn/extract"
 	"github.com/qdm12/gluetun/internal/provider"
-	"github.com/qdm12/gluetun/internal/publicip/ipinfo"
 	"github.com/qdm12/gluetun/internal/storage"
 	"github.com/qdm12/gluetun/internal/updater/resolver"
 )
@@ -29,14 +28,19 @@ type Unzipper interface {
 
 type ParallelResolver interface {
 	Resolve(ctx context.Context, settings resolver.ParallelSettings) (
-		hostToIPs map[string][]net.IP, warnings []string, err error)
+		hostToIPs map[string][]netip.Addr, warnings []string, err error)
 }
 
 type IPFetcher interface {
-	FetchMultiInfo(ctx context.Context, ips []net.IP) (data []ipinfo.Response, err error)
+	FetchInfo(ctx context.Context, ip netip.Addr) (data models.PublicIP, 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

@@ -14,7 +14,7 @@ import (
 	"github.com/qdm12/gluetun/internal/constants/providers"
 	"github.com/qdm12/gluetun/internal/openvpn/extract"
 	"github.com/qdm12/gluetun/internal/provider"
-	"github.com/qdm12/gluetun/internal/publicip/ipinfo"
+	"github.com/qdm12/gluetun/internal/publicip/api"
 	"github.com/qdm12/gluetun/internal/storage"
 	"github.com/qdm12/gluetun/internal/updater"
 	"github.com/qdm12/gluetun/internal/updater/resolver"
@@ -35,7 +35,7 @@ type UpdaterLogger interface {
 func (c *CLI) Update(ctx context.Context, args []string, logger UpdaterLogger) error {
 	options := settings.Updater{}
 	var endUserMode, maintainerMode, updateAll bool
-	var csvProviders string
+	var csvProviders, ipToken string
 	flagSet := flag.NewFlagSet("update", flag.ExitOnError)
 	flagSet.BoolVar(&endUserMode, "enduser", false, "Write results to /gluetun/servers.json (for end users)")
 	flagSet.BoolVar(&maintainerMode, "maintainer", false,
@@ -46,19 +46,20 @@ func (c *CLI) Update(ctx context.Context, args []string, logger UpdaterLogger) e
 		"Minimum ratio of servers to find for the update to succeed")
 	flagSet.BoolVar(&updateAll, "all", false, "Update servers for all VPN providers")
 	flagSet.StringVar(&csvProviders, "providers", "", "CSV string of VPN providers to update server data for")
+	flagSet.StringVar(&ipToken, "ip-token", "", "IP data service token (e.g. ipinfo.io) to use")
 	if err := flagSet.Parse(args); err != nil {
 		return err
 	}
 
 	if !endUserMode && !maintainerMode {
-		return ErrModeUnspecified
+		return fmt.Errorf("%w", ErrModeUnspecified)
 	}
 
 	if updateAll {
 		options.Providers = providers.All()
 	} else {
 		if csvProviders == "" {
-			return ErrNoProviderSpecified
+			return fmt.Errorf("%w", ErrNoProviderSpecified)
 		}
 		options.Providers = strings.Split(csvProviders, ",")
 	}
@@ -72,14 +73,17 @@ 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
 	httpClient := &http.Client{Timeout: clientTimeout}
 	unzipper := unzip.New(httpClient)
 	parallelResolver := resolver.NewParallelResolver(options.DNSAddress)
-	ipFetcher := ipinfo.New(httpClient)
+	ipFetcher, err := api.New(api.IPInfo, httpClient, ipToken)
+	if err != nil {
+		return fmt.Errorf("creating public IP API client: %w", err)
+	}
 	openvpnFileExtractor := extract.New()
 
 	providers := provider.NewProviders(storage, time.Now, logger, httpClient,
@@ -88,13 +92,13 @@ 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

@@ -2,9 +2,9 @@ package settings
 
 import (
 	"fmt"
-	"net"
+	"net/netip"
 
-	"github.com/qdm12/gluetun/internal/configuration/settings/helpers"
+	"github.com/qdm12/gosettings"
 	"github.com/qdm12/gotree"
 )
 
@@ -13,13 +13,17 @@ type DNS struct {
 	// ServerAddress is the DNS server to use inside
 	// the Go program and for the system.
 	// It defaults to '127.0.0.1' to be used with the
-	// DoT server. It cannot be nil in the internal
+	// DoT server. It cannot be the zero value in the internal
 	// state.
-	ServerAddress net.IP
-	// KeepNameserver is true if the Docker DNS server
-	// found in /etc/resolv.conf should be kept.
-	// Note settings this to true will go around the
-	// DoT server blocking.
+	ServerAddress netip.Addr
+	// KeepNameserver is true if the existing DNS server
+	// found in /etc/resolv.conf should be used
+	// Note setting this to true will likely DNS traffic
+	// outside the VPN tunnel since it would go through
+	// the local DNS server of your Docker/Kubernetes
+	// configuration, which is likely not going through the tunnel.
+	// This will also disable the DNS over TLS server and the
+	// `ServerAddress` field will be ignored.
 	// It defaults to false and cannot be nil in the
 	// internal state.
 	KeepNameserver *bool
@@ -31,7 +35,7 @@ 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
@@ -39,8 +43,8 @@ func (d DNS) validate() (err error) {
 
 func (d *DNS) Copy() (copied DNS) {
 	return DNS{
-		ServerAddress:  helpers.CopyIP(d.ServerAddress),
-		KeepNameserver: helpers.CopyBoolPtr(d.KeepNameserver),
+		ServerAddress:  d.ServerAddress,
+		KeepNameserver: gosettings.CopyPointer(d.KeepNameserver),
 		DoT:            d.DoT.copy(),
 	}
 }
@@ -48,8 +52,8 @@ func (d *DNS) Copy() (copied DNS) {
 // mergeWith merges the other settings into any
 // unset field of the receiver settings object.
 func (d *DNS) mergeWith(other DNS) {
-	d.ServerAddress = helpers.MergeWithIP(d.ServerAddress, other.ServerAddress)
-	d.KeepNameserver = helpers.MergeWithBool(d.KeepNameserver, other.KeepNameserver)
+	d.ServerAddress = gosettings.MergeWithValidator(d.ServerAddress, other.ServerAddress)
+	d.KeepNameserver = gosettings.MergeWithPointer(d.KeepNameserver, other.KeepNameserver)
 	d.DoT.mergeWith(other.DoT)
 }
 
@@ -57,15 +61,15 @@ func (d *DNS) mergeWith(other DNS) {
 // settings object with any field set in the other
 // settings.
 func (d *DNS) overrideWith(other DNS) {
-	d.ServerAddress = helpers.OverrideWithIP(d.ServerAddress, other.ServerAddress)
-	d.KeepNameserver = helpers.OverrideWithBool(d.KeepNameserver, other.KeepNameserver)
+	d.ServerAddress = gosettings.OverrideWithValidator(d.ServerAddress, other.ServerAddress)
+	d.KeepNameserver = gosettings.OverrideWithPointer(d.KeepNameserver, other.KeepNameserver)
 	d.DoT.overrideWith(other.DoT)
 }
 
 func (d *DNS) setDefaults() {
-	localhost := net.IPv4(127, 0, 0, 1) //nolint:gomnd
-	d.ServerAddress = helpers.DefaultIP(d.ServerAddress, localhost)
-	d.KeepNameserver = helpers.DefaultBool(d.KeepNameserver, false)
+	localhost := netip.AddrFrom4([4]byte{127, 0, 0, 1})
+	d.ServerAddress = gosettings.DefaultValidator(d.ServerAddress, localhost)
+	d.KeepNameserver = gosettings.DefaultPointer(d.KeepNameserver, false)
 	d.DoT.setDefaults()
 }
 
@@ -75,8 +79,11 @@ func (d DNS) String() string {
 
 func (d DNS) toLinesNode() (node *gotree.Node) {
 	node = gotree.New("DNS settings:")
+	node.Appendf("Keep existing nameserver(s): %s", gosettings.BoolToYesNo(d.KeepNameserver))
+	if *d.KeepNameserver {
+		return node
+	}
 	node.Appendf("DNS server address to use: %s", d.ServerAddress)
-	node.Appendf("Keep existing nameserver(s): %s", helpers.BoolPtrToYesNo(d.KeepNameserver))
 	node.AppendNode(d.DoT.toLinesNode())
 	return node
 }

internal/configuration/settings/dnsblacklist.go

@@ -3,12 +3,12 @@ package settings
 import (
 	"errors"
 	"fmt"
+	"net/netip"
 	"regexp"
 
 	"github.com/qdm12/dns/pkg/blacklist"
-	"github.com/qdm12/gluetun/internal/configuration/settings/helpers"
+	"github.com/qdm12/gosettings"
 	"github.com/qdm12/gotree"
-	"inet.af/netaddr"
 )
 
 // DNSBlacklist is settings for the DNS blacklist building.
@@ -18,14 +18,14 @@ type DNSBlacklist struct {
 	BlockSurveillance    *bool
 	AllowedHosts         []string
 	AddBlockedHosts      []string
-	AddBlockedIPs        []netaddr.IP
-	AddBlockedIPPrefixes []netaddr.IPPrefix
+	AddBlockedIPs        []netip.Addr
+	AddBlockedIPPrefixes []netip.Prefix
 }
 
 func (b *DNSBlacklist) setDefaults() {
-	b.BlockMalicious = helpers.DefaultBool(b.BlockMalicious, true)
-	b.BlockAds = helpers.DefaultBool(b.BlockAds, false)
-	b.BlockSurveillance = helpers.DefaultBool(b.BlockSurveillance, true)
+	b.BlockMalicious = gosettings.DefaultPointer(b.BlockMalicious, true)
+	b.BlockAds = gosettings.DefaultPointer(b.BlockAds, false)
+	b.BlockSurveillance = gosettings.DefaultPointer(b.BlockSurveillance, true)
 }
 
 var hostRegex = regexp.MustCompile(`^([a-zA-Z0-9]|[a-zA-Z0-9_][a-zA-Z0-9\-_]{0,61}[a-zA-Z0-9_])(\.([a-zA-Z0-9]|[a-zA-Z0-9_][a-zA-Z0-9\-_]{0,61}[a-zA-Z0-9]))*$`) //nolint:lll
@@ -53,34 +53,34 @@ func (b DNSBlacklist) validate() (err error) {
 
 func (b DNSBlacklist) copy() (copied DNSBlacklist) {
 	return DNSBlacklist{
-		BlockMalicious:       helpers.CopyBoolPtr(b.BlockMalicious),
-		BlockAds:             helpers.CopyBoolPtr(b.BlockAds),
-		BlockSurveillance:    helpers.CopyBoolPtr(b.BlockSurveillance),
-		AllowedHosts:         helpers.CopyStringSlice(b.AllowedHosts),
-		AddBlockedHosts:      helpers.CopyStringSlice(b.AddBlockedHosts),
-		AddBlockedIPs:        helpers.CopyNetaddrIPsSlice(b.AddBlockedIPs),
-		AddBlockedIPPrefixes: helpers.CopyIPPrefixSlice(b.AddBlockedIPPrefixes),
+		BlockMalicious:       gosettings.CopyPointer(b.BlockMalicious),
+		BlockAds:             gosettings.CopyPointer(b.BlockAds),
+		BlockSurveillance:    gosettings.CopyPointer(b.BlockSurveillance),
+		AllowedHosts:         gosettings.CopySlice(b.AllowedHosts),
+		AddBlockedHosts:      gosettings.CopySlice(b.AddBlockedHosts),
+		AddBlockedIPs:        gosettings.CopySlice(b.AddBlockedIPs),
+		AddBlockedIPPrefixes: gosettings.CopySlice(b.AddBlockedIPPrefixes),
 	}
 }
 
 func (b *DNSBlacklist) mergeWith(other DNSBlacklist) {
-	b.BlockMalicious = helpers.MergeWithBool(b.BlockMalicious, other.BlockMalicious)
-	b.BlockAds = helpers.MergeWithBool(b.BlockAds, other.BlockAds)
-	b.BlockSurveillance = helpers.MergeWithBool(b.BlockSurveillance, other.BlockSurveillance)
-	b.AllowedHosts = helpers.MergeStringSlices(b.AllowedHosts, other.AllowedHosts)
-	b.AddBlockedHosts = helpers.MergeStringSlices(b.AddBlockedHosts, other.AddBlockedHosts)
-	b.AddBlockedIPs = helpers.MergeNetaddrIPsSlices(b.AddBlockedIPs, other.AddBlockedIPs)
-	b.AddBlockedIPPrefixes = helpers.MergeIPPrefixesSlices(b.AddBlockedIPPrefixes, other.AddBlockedIPPrefixes)
+	b.BlockMalicious = gosettings.MergeWithPointer(b.BlockMalicious, other.BlockMalicious)
+	b.BlockAds = gosettings.MergeWithPointer(b.BlockAds, other.BlockAds)
+	b.BlockSurveillance = gosettings.MergeWithPointer(b.BlockSurveillance, other.BlockSurveillance)
+	b.AllowedHosts = gosettings.MergeWithSlice(b.AllowedHosts, other.AllowedHosts)
+	b.AddBlockedHosts = gosettings.MergeWithSlice(b.AddBlockedHosts, other.AddBlockedHosts)
+	b.AddBlockedIPs = gosettings.MergeWithSlice(b.AddBlockedIPs, other.AddBlockedIPs)
+	b.AddBlockedIPPrefixes = gosettings.MergeWithSlice(b.AddBlockedIPPrefixes, other.AddBlockedIPPrefixes)
 }
 
 func (b *DNSBlacklist) overrideWith(other DNSBlacklist) {
-	b.BlockMalicious = helpers.OverrideWithBool(b.BlockMalicious, other.BlockMalicious)
-	b.BlockAds = helpers.OverrideWithBool(b.BlockAds, other.BlockAds)
-	b.BlockSurveillance = helpers.OverrideWithBool(b.BlockSurveillance, other.BlockSurveillance)
-	b.AllowedHosts = helpers.OverrideWithStringSlice(b.AllowedHosts, other.AllowedHosts)
-	b.AddBlockedHosts = helpers.OverrideWithStringSlice(b.AddBlockedHosts, other.AddBlockedHosts)
-	b.AddBlockedIPs = helpers.OverrideWithNetaddrIPsSlice(b.AddBlockedIPs, other.AddBlockedIPs)
-	b.AddBlockedIPPrefixes = helpers.OverrideWithIPPrefixesSlice(b.AddBlockedIPPrefixes, other.AddBlockedIPPrefixes)
+	b.BlockMalicious = gosettings.OverrideWithPointer(b.BlockMalicious, other.BlockMalicious)
+	b.BlockAds = gosettings.OverrideWithPointer(b.BlockAds, other.BlockAds)
+	b.BlockSurveillance = gosettings.OverrideWithPointer(b.BlockSurveillance, other.BlockSurveillance)
+	b.AllowedHosts = gosettings.OverrideWithSlice(b.AllowedHosts, other.AllowedHosts)
+	b.AddBlockedHosts = gosettings.OverrideWithSlice(b.AddBlockedHosts, other.AddBlockedHosts)
+	b.AddBlockedIPs = gosettings.OverrideWithSlice(b.AddBlockedIPs, other.AddBlockedIPs)
+	b.AddBlockedIPPrefixes = gosettings.OverrideWithSlice(b.AddBlockedIPPrefixes, other.AddBlockedIPPrefixes)
 }
 
 func (b DNSBlacklist) ToBlacklistFormat() (settings blacklist.BuilderSettings, err error) {
@@ -90,8 +90,8 @@ func (b DNSBlacklist) ToBlacklistFormat() (settings blacklist.BuilderSettings, e
 		BlockSurveillance:    *b.BlockSurveillance,
 		AllowedHosts:         b.AllowedHosts,
 		AddBlockedHosts:      b.AddBlockedHosts,
-		AddBlockedIPs:        b.AddBlockedIPs,
-		AddBlockedIPPrefixes: b.AddBlockedIPPrefixes,
+		AddBlockedIPs:        netipAddressesToNetaddrIPs(b.AddBlockedIPs),
+		AddBlockedIPPrefixes: netipPrefixesToNetaddrIPPrefixes(b.AddBlockedIPPrefixes),
 	}, nil
 }
 
@@ -102,9 +102,9 @@ func (b DNSBlacklist) String() string {
 func (b DNSBlacklist) toLinesNode() (node *gotree.Node) {
 	node = gotree.New("DNS filtering settings:")
 
-	node.Appendf("Block malicious: %s", helpers.BoolPtrToYesNo(b.BlockMalicious))
-	node.Appendf("Block ads: %s", helpers.BoolPtrToYesNo(b.BlockAds))
-	node.Appendf("Block surveillance: %s", helpers.BoolPtrToYesNo(b.BlockSurveillance))
+	node.Appendf("Block malicious: %s", gosettings.BoolToYesNo(b.BlockMalicious))
+	node.Appendf("Block ads: %s", gosettings.BoolToYesNo(b.BlockAds))
+	node.Appendf("Block surveillance: %s", gosettings.BoolToYesNo(b.BlockSurveillance))
 
 	if len(b.AllowedHosts) > 0 {
 		allowedHostsNode := node.Appendf("Allowed hosts:")

internal/configuration/settings/dot.go

@@ -5,7 +5,7 @@ import (
 	"fmt"
 	"time"
 
-	"github.com/qdm12/gluetun/internal/configuration/settings/helpers"
+	"github.com/qdm12/gosettings"
 	"github.com/qdm12/gotree"
 )
 
@@ -54,8 +54,8 @@ func (d DoT) validate() (err error) {
 
 func (d *DoT) copy() (copied DoT) {
 	return DoT{
-		Enabled:      helpers.CopyBoolPtr(d.Enabled),
-		UpdatePeriod: helpers.CopyDurationPtr(d.UpdatePeriod),
+		Enabled:      gosettings.CopyPointer(d.Enabled),
+		UpdatePeriod: gosettings.CopyPointer(d.UpdatePeriod),
 		Unbound:      d.Unbound.copy(),
 		Blacklist:    d.Blacklist.copy(),
 	}
@@ -64,8 +64,8 @@ func (d *DoT) copy() (copied DoT) {
 // mergeWith merges the other settings into any
 // unset field of the receiver settings object.
 func (d *DoT) mergeWith(other DoT) {
-	d.Enabled = helpers.MergeWithBool(d.Enabled, other.Enabled)
-	d.UpdatePeriod = helpers.MergeWithDuration(d.UpdatePeriod, other.UpdatePeriod)
+	d.Enabled = gosettings.MergeWithPointer(d.Enabled, other.Enabled)
+	d.UpdatePeriod = gosettings.MergeWithPointer(d.UpdatePeriod, other.UpdatePeriod)
 	d.Unbound.mergeWith(other.Unbound)
 	d.Blacklist.mergeWith(other.Blacklist)
 }
@@ -74,16 +74,16 @@ func (d *DoT) mergeWith(other DoT) {
 // settings object with any field set in the other
 // settings.
 func (d *DoT) overrideWith(other DoT) {
-	d.Enabled = helpers.OverrideWithBool(d.Enabled, other.Enabled)
-	d.UpdatePeriod = helpers.OverrideWithDuration(d.UpdatePeriod, other.UpdatePeriod)
+	d.Enabled = gosettings.OverrideWithPointer(d.Enabled, other.Enabled)
+	d.UpdatePeriod = gosettings.OverrideWithPointer(d.UpdatePeriod, other.UpdatePeriod)
 	d.Unbound.overrideWith(other.Unbound)
 	d.Blacklist.overrideWith(other.Blacklist)
 }
 
 func (d *DoT) setDefaults() {
-	d.Enabled = helpers.DefaultBool(d.Enabled, true)
+	d.Enabled = gosettings.DefaultPointer(d.Enabled, true)
 	const defaultUpdatePeriod = 24 * time.Hour
-	d.UpdatePeriod = helpers.DefaultDuration(d.UpdatePeriod, defaultUpdatePeriod)
+	d.UpdatePeriod = gosettings.DefaultPointer(d.UpdatePeriod, defaultUpdatePeriod)
 	d.Unbound.setDefaults()
 	d.Blacklist.setDefaults()
 }
@@ -95,12 +95,12 @@ func (d DoT) String() string {
 func (d DoT) toLinesNode() (node *gotree.Node) {
 	node = gotree.New("DNS over TLS settings:")
 
-	node.Appendf("Enabled: %s", helpers.BoolPtrToYesNo(d.Enabled))
+	node.Appendf("Enabled: %s", gosettings.BoolToYesNo(d.Enabled))
 	if !*d.Enabled {
 		return node
 	}
 
-	update := "disabled"
+	update := "disabled" //nolint:goconst
 	if *d.UpdatePeriod > 0 {
 		update = "every " + d.UpdatePeriod.String()
 	}

internal/configuration/settings/errors.go

@@ -5,9 +5,11 @@ import "errors"
 var (
 	ErrCityNotValid                    = errors.New("the city specified is not valid")
 	ErrControlServerPrivilegedPort     = errors.New("cannot use privileged port without running as root")
+	ErrCategoryNotValid                = errors.New("the category specified is not valid")
 	ErrCountryNotValid                 = errors.New("the country specified is not valid")
 	ErrFilepathMissing                 = errors.New("filepath is missing")
-	ErrFirewallZeroPort                = errors.New("cannot have a zero port to block")
+	ErrFirewallZeroPort                = errors.New("cannot have a zero port")
+	ErrFirewallPublicOutboundSubnet    = errors.New("outbound subnet has an unspecified address")
 	ErrHostnameNotValid                = errors.New("the hostname specified is not valid")
 	ErrISPNotValid                     = errors.New("the ISP specified is not valid")
 	ErrMinRatioNotValid                = errors.New("minimum ratio is not valid")
@@ -17,6 +19,7 @@ var (
 	ErrOpenVPNCustomPortNotAllowed     = errors.New("custom endpoint port is not allowed")
 	ErrOpenVPNEncryptionPresetNotValid = errors.New("PIA encryption preset is not valid")
 	ErrOpenVPNInterfaceNotValid        = errors.New("interface name is not valid")
+	ErrOpenVPNKeyPassphraseIsEmpty     = errors.New("key passphrase is empty")
 	ErrOpenVPNMSSFixIsTooHigh          = errors.New("mssfix option value is too high")
 	ErrOpenVPNPasswordIsEmpty          = errors.New("password is empty")
 	ErrOpenVPNTCPNotSupported          = errors.New("TCP protocol is not supported")
@@ -33,13 +36,18 @@ var (
 	ErrUpdaterPeriodTooSmall           = errors.New("VPN server data updater period is too small")
 	ErrVPNProviderNameNotValid         = errors.New("VPN provider name is not valid")
 	ErrVPNTypeNotValid                 = errors.New("VPN type is not valid")
+	ErrWireguardAllowedIPNotSet        = errors.New("allowed IP is not set")
+	ErrWireguardAllowedIPsNotSet       = errors.New("allowed IPs is not set")
 	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

@@ -2,9 +2,9 @@ package settings
 
 import (
 	"fmt"
-	"net"
+	"net/netip"
 
-	"github.com/qdm12/gluetun/internal/configuration/settings/helpers"
+	"github.com/qdm12/gosettings"
 	"github.com/qdm12/gotree"
 )
 
@@ -12,7 +12,7 @@ import (
 type Firewall struct {
 	VPNInputPorts   []uint16
 	InputPorts      []uint16
-	OutboundSubnets []net.IPNet
+	OutboundSubnets []netip.Prefix
 	Enabled         *bool
 	Debug           *bool
 }
@@ -26,6 +26,12 @@ func (f Firewall) validate() (err error) {
 		return fmt.Errorf("input ports: %w", ErrFirewallZeroPort)
 	}
 
+	for _, subnet := range f.OutboundSubnets {
+		if subnet.Addr().IsUnspecified() {
+			return fmt.Errorf("%w: %s", ErrFirewallPublicOutboundSubnet, subnet)
+		}
+	}
+
 	return nil
 }
 
@@ -40,11 +46,11 @@ func hasZeroPort(ports []uint16) (has bool) {
 
 func (f *Firewall) copy() (copied Firewall) {
 	return Firewall{
-		VPNInputPorts:   helpers.CopyUint16Slice(f.VPNInputPorts),
-		InputPorts:      helpers.CopyUint16Slice(f.InputPorts),
-		OutboundSubnets: helpers.CopyIPNetSlice(f.OutboundSubnets),
-		Enabled:         helpers.CopyBoolPtr(f.Enabled),
-		Debug:           helpers.CopyBoolPtr(f.Debug),
+		VPNInputPorts:   gosettings.CopySlice(f.VPNInputPorts),
+		InputPorts:      gosettings.CopySlice(f.InputPorts),
+		OutboundSubnets: gosettings.CopySlice(f.OutboundSubnets),
+		Enabled:         gosettings.CopyPointer(f.Enabled),
+		Debug:           gosettings.CopyPointer(f.Debug),
 	}
 }
 
@@ -53,27 +59,27 @@ func (f *Firewall) copy() (copied Firewall) {
 // It merges values of slices together, even if they
 // are set in the receiver settings.
 func (f *Firewall) mergeWith(other Firewall) {
-	f.VPNInputPorts = helpers.MergeUint16Slices(f.VPNInputPorts, other.VPNInputPorts)
-	f.InputPorts = helpers.MergeUint16Slices(f.InputPorts, other.InputPorts)
-	f.OutboundSubnets = helpers.MergeIPNetsSlices(f.OutboundSubnets, other.OutboundSubnets)
-	f.Enabled = helpers.MergeWithBool(f.Enabled, other.Enabled)
-	f.Debug = helpers.MergeWithBool(f.Debug, other.Debug)
+	f.VPNInputPorts = gosettings.MergeWithSlice(f.VPNInputPorts, other.VPNInputPorts)
+	f.InputPorts = gosettings.MergeWithSlice(f.InputPorts, other.InputPorts)
+	f.OutboundSubnets = gosettings.MergeWithSlice(f.OutboundSubnets, other.OutboundSubnets)
+	f.Enabled = gosettings.MergeWithPointer(f.Enabled, other.Enabled)
+	f.Debug = gosettings.MergeWithPointer(f.Debug, other.Debug)
 }
 
 // overrideWith overrides fields of the receiver
 // settings object with any field set in the other
 // settings.
 func (f *Firewall) overrideWith(other Firewall) {
-	f.VPNInputPorts = helpers.OverrideWithUint16Slice(f.VPNInputPorts, other.VPNInputPorts)
-	f.InputPorts = helpers.OverrideWithUint16Slice(f.InputPorts, other.InputPorts)
-	f.OutboundSubnets = helpers.OverrideWithIPNetsSlice(f.OutboundSubnets, other.OutboundSubnets)
-	f.Enabled = helpers.OverrideWithBool(f.Enabled, other.Enabled)
-	f.Debug = helpers.OverrideWithBool(f.Debug, other.Debug)
+	f.VPNInputPorts = gosettings.OverrideWithSlice(f.VPNInputPorts, other.VPNInputPorts)
+	f.InputPorts = gosettings.OverrideWithSlice(f.InputPorts, other.InputPorts)
+	f.OutboundSubnets = gosettings.OverrideWithSlice(f.OutboundSubnets, other.OutboundSubnets)
+	f.Enabled = gosettings.OverrideWithPointer(f.Enabled, other.Enabled)
+	f.Debug = gosettings.OverrideWithPointer(f.Debug, other.Debug)
 }
 
 func (f *Firewall) setDefaults() {
-	f.Enabled = helpers.DefaultBool(f.Enabled, true)
-	f.Debug = helpers.DefaultBool(f.Debug, false)
+	f.Enabled = gosettings.DefaultPointer(f.Enabled, true)
+	f.Debug = gosettings.DefaultPointer(f.Debug, false)
 }
 
 func (f Firewall) String() string {
@@ -83,7 +89,7 @@ func (f Firewall) String() string {
 func (f Firewall) toLinesNode() (node *gotree.Node) {
 	node = gotree.New("Firewall settings:")
 
-	node.Appendf("Enabled: %s", helpers.BoolPtrToYesNo(f.Enabled))
+	node.Appendf("Enabled: %s", gosettings.BoolToYesNo(f.Enabled))
 	if !*f.Enabled {
 		return node
 	}
@@ -109,7 +115,8 @@ 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/firewall_test.go

@@ -0,0 +1,74 @@
+package settings
+
+import (
+	"net/netip"
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+)
+
+func Test_Firewall_validate(t *testing.T) {
+	t.Parallel()
+
+	testCases := map[string]struct {
+		firewall   Firewall
+		errWrapped error
+		errMessage string
+	}{
+		"empty": {},
+		"zero_vpn_input_port": {
+			firewall: Firewall{
+				VPNInputPorts: []uint16{0},
+			},
+			errWrapped: ErrFirewallZeroPort,
+			errMessage: "VPN input ports: cannot have a zero port",
+		},
+		"zero_input_port": {
+			firewall: Firewall{
+				InputPorts: []uint16{0},
+			},
+			errWrapped: ErrFirewallZeroPort,
+			errMessage: "input ports: cannot have a zero port",
+		},
+		"unspecified_outbound_subnet": {
+			firewall: Firewall{
+				OutboundSubnets: []netip.Prefix{
+					netip.MustParsePrefix("0.0.0.0/0"),
+				},
+			},
+			errWrapped: ErrFirewallPublicOutboundSubnet,
+			errMessage: "outbound subnet has an unspecified address: 0.0.0.0/0",
+		},
+		"public_outbound_subnet": {
+			firewall: Firewall{
+				OutboundSubnets: []netip.Prefix{
+					netip.MustParsePrefix("1.2.3.4/32"),
+				},
+			},
+		},
+		"valid_settings": {
+			firewall: Firewall{
+				VPNInputPorts: []uint16{100, 101},
+				InputPorts:    []uint16{200, 201},
+				OutboundSubnets: []netip.Prefix{
+					netip.MustParsePrefix("192.168.1.0/24"),
+					netip.MustParsePrefix("10.10.1.1/32"),
+				},
+			},
+		},
+	}
+
+	for name, testCase := range testCases {
+		testCase := testCase
+		t.Run(name, func(t *testing.T) {
+			t.Parallel()
+
+			err := testCase.firewall.validate()
+
+			assert.ErrorIs(t, err, testCase.errWrapped)
+			if testCase.errWrapped != nil {
+				assert.EqualError(t, err, testCase.errMessage)
+			}
+		})
+	}
+}

internal/configuration/settings/health.go

@@ -3,8 +3,9 @@ package settings
 import (
 	"fmt"
 	"os"
+	"time"
 
-	"github.com/qdm12/gluetun/internal/configuration/settings/helpers"
+	"github.com/qdm12/gosettings"
 	"github.com/qdm12/gotree"
 	"github.com/qdm12/govalid/address"
 )
@@ -15,16 +16,28 @@ type Health struct {
 	// for the health check server.
 	// It cannot be the empty string in the internal state.
 	ServerAddress string
+	// ReadHeaderTimeout is the HTTP server header read timeout
+	// duration of the HTTP server. It defaults to 100 milliseconds.
+	ReadHeaderTimeout time.Duration
+	// ReadTimeout is the HTTP read timeout duration of the
+	// HTTP server. It defaults to 500 milliseconds.
+	ReadTimeout time.Duration
 	// TargetAddress is the address (host or host:port)
 	// to TCP dial to periodically for the health check.
 	// It cannot be the empty string in the internal state.
 	TargetAddress string
-	VPN           HealthyWait
+	// SuccessWait is the duration to wait to re-run the
+	// healthcheck after a successful healthcheck.
+	// It defaults to 5 seconds and cannot be zero in
+	// the internal state.
+	SuccessWait time.Duration
+	// VPN has health settings specific to the VPN loop.
+	VPN HealthyWait
 }
 
 func (h Health) Validate() (err error) {
 	uid := os.Getuid()
-	_, err = address.Validate(h.ServerAddress,
+	err = address.Validate(h.ServerAddress,
 		address.OptionListening(uid))
 	if err != nil {
 		return fmt.Errorf("server listening address is not valid: %w", err)
@@ -40,17 +53,23 @@ func (h Health) Validate() (err error) {
 
 func (h *Health) copy() (copied Health) {
 	return Health{
-		ServerAddress: h.ServerAddress,
-		TargetAddress: h.TargetAddress,
-		VPN:           h.VPN.copy(),
+		ServerAddress:     h.ServerAddress,
+		ReadHeaderTimeout: h.ReadHeaderTimeout,
+		ReadTimeout:       h.ReadTimeout,
+		TargetAddress:     h.TargetAddress,
+		SuccessWait:       h.SuccessWait,
+		VPN:               h.VPN.copy(),
 	}
 }
 
 // MergeWith merges the other settings into any
 // unset field of the receiver settings object.
 func (h *Health) MergeWith(other Health) {
-	h.ServerAddress = helpers.MergeWithString(h.ServerAddress, other.ServerAddress)
-	h.TargetAddress = helpers.MergeWithString(h.TargetAddress, other.TargetAddress)
+	h.ServerAddress = gosettings.MergeWithString(h.ServerAddress, other.ServerAddress)
+	h.ReadHeaderTimeout = gosettings.MergeWithNumber(h.ReadHeaderTimeout, other.ReadHeaderTimeout)
+	h.ReadTimeout = gosettings.MergeWithNumber(h.ReadTimeout, other.ReadTimeout)
+	h.TargetAddress = gosettings.MergeWithString(h.TargetAddress, other.TargetAddress)
+	h.SuccessWait = gosettings.MergeWithNumber(h.SuccessWait, other.SuccessWait)
 	h.VPN.mergeWith(other.VPN)
 }
 
@@ -58,14 +77,23 @@ func (h *Health) MergeWith(other Health) {
 // settings object with any field set in the other
 // settings.
 func (h *Health) OverrideWith(other Health) {
-	h.ServerAddress = helpers.OverrideWithString(h.ServerAddress, other.ServerAddress)
-	h.TargetAddress = helpers.OverrideWithString(h.TargetAddress, other.TargetAddress)
+	h.ServerAddress = gosettings.OverrideWithString(h.ServerAddress, other.ServerAddress)
+	h.ReadHeaderTimeout = gosettings.OverrideWithNumber(h.ReadHeaderTimeout, other.ReadHeaderTimeout)
+	h.ReadTimeout = gosettings.OverrideWithNumber(h.ReadTimeout, other.ReadTimeout)
+	h.TargetAddress = gosettings.OverrideWithString(h.TargetAddress, other.TargetAddress)
+	h.SuccessWait = gosettings.OverrideWithNumber(h.SuccessWait, other.SuccessWait)
 	h.VPN.overrideWith(other.VPN)
 }
 
 func (h *Health) SetDefaults() {
-	h.ServerAddress = helpers.DefaultString(h.ServerAddress, "127.0.0.1:9999")
-	h.TargetAddress = helpers.DefaultString(h.TargetAddress, "cloudflare.com:443")
+	h.ServerAddress = gosettings.DefaultString(h.ServerAddress, "127.0.0.1:9999")
+	const defaultReadHeaderTimeout = 100 * time.Millisecond
+	h.ReadHeaderTimeout = gosettings.DefaultNumber(h.ReadHeaderTimeout, defaultReadHeaderTimeout)
+	const defaultReadTimeout = 500 * time.Millisecond
+	h.ReadTimeout = gosettings.DefaultNumber(h.ReadTimeout, defaultReadTimeout)
+	h.TargetAddress = gosettings.DefaultString(h.TargetAddress, "cloudflare.com:443")
+	const defaultSuccessWait = 5 * time.Second
+	h.SuccessWait = gosettings.DefaultNumber(h.SuccessWait, defaultSuccessWait)
 	h.VPN.setDefaults()
 }
 
@@ -77,6 +105,9 @@ func (h Health) toLinesNode() (node *gotree.Node) {
 	node = gotree.New("Health settings:")
 	node.Appendf("Server listening address: %s", h.ServerAddress)
 	node.Appendf("Target address: %s", h.TargetAddress)
+	node.Appendf("Duration to wait after success: %s", h.SuccessWait)
+	node.Appendf("Read header timeout: %s", h.ReadHeaderTimeout)
+	node.Appendf("Read timeout: %s", h.ReadTimeout)
 	node.AppendNode(h.VPN.toLinesNode("VPN"))
 	return node
 }

internal/configuration/settings/healthywait.go

@@ -3,7 +3,7 @@ package settings
 import (
 	"time"
 
-	"github.com/qdm12/gluetun/internal/configuration/settings/helpers"
+	"github.com/qdm12/gosettings"
 	"github.com/qdm12/gotree"
 )
 
@@ -27,31 +27,31 @@ func (h HealthyWait) validate() (err error) {
 // unset field of the receiver settings object.
 func (h *HealthyWait) copy() (copied HealthyWait) {
 	return HealthyWait{
-		Initial:  helpers.CopyDurationPtr(h.Initial),
-		Addition: helpers.CopyDurationPtr(h.Addition),
+		Initial:  gosettings.CopyPointer(h.Initial),
+		Addition: gosettings.CopyPointer(h.Addition),
 	}
 }
 
 // mergeWith merges the other settings into any
 // unset field of the receiver settings object.
 func (h *HealthyWait) mergeWith(other HealthyWait) {
-	h.Initial = helpers.MergeWithDuration(h.Initial, other.Initial)
-	h.Addition = helpers.MergeWithDuration(h.Addition, other.Addition)
+	h.Initial = gosettings.MergeWithPointer(h.Initial, other.Initial)
+	h.Addition = gosettings.MergeWithPointer(h.Addition, other.Addition)
 }
 
 // overrideWith overrides fields of the receiver
 // settings object with any field set in the other
 // settings.
 func (h *HealthyWait) overrideWith(other HealthyWait) {
-	h.Initial = helpers.OverrideWithDuration(h.Initial, other.Initial)
-	h.Addition = helpers.OverrideWithDuration(h.Addition, other.Addition)
+	h.Initial = gosettings.OverrideWithPointer(h.Initial, other.Initial)
+	h.Addition = gosettings.OverrideWithPointer(h.Addition, other.Addition)
 }
 
 func (h *HealthyWait) setDefaults() {
 	const initialDurationDefault = 6 * time.Second
 	const additionDurationDefault = 5 * time.Second
-	h.Initial = helpers.DefaultDuration(h.Initial, initialDurationDefault)
-	h.Addition = helpers.DefaultDuration(h.Addition, additionDurationDefault)
+	h.Initial = gosettings.DefaultPointer(h.Initial, initialDurationDefault)
+	h.Addition = gosettings.DefaultPointer(h.Addition, additionDurationDefault)
 }
 
 func (h HealthyWait) String() string {

internal/configuration/settings/helpers/belong.go

@@ -1,12 +1,6 @@
 package helpers
 
-import (
-	"errors"
-	"fmt"
-	"strings"
-)
-
-func IsOneOf(value string, choices ...string) (ok bool) {
+func IsOneOf[T comparable](value T, choices ...T) (ok bool) {
 	for _, choice := range choices {
 		if value == choice {
 			return true
@@ -14,39 +8,3 @@ func IsOneOf(value string, choices ...string) (ok bool) {
 	}
 	return false
 }
-
-var (
-	ErrNoChoice      = errors.New("one or more values is set but there is no possible value available")
-	ErrValueNotOneOf = errors.New("value is not one of the possible choices")
-)
-
-func AreAllOneOf(values, choices []string) (err error) {
-	if len(values) > 0 && len(choices) == 0 {
-		return ErrNoChoice
-	}
-
-	set := make(map[string]struct{}, len(choices))
-	for _, choice := range choices {
-		choice = strings.ToLower(choice)
-		set[choice] = struct{}{}
-	}
-
-	for _, value := range values {
-		_, ok := set[value]
-		if !ok {
-			return fmt.Errorf("%w: value %q, choices available are %s",
-				ErrValueNotOneOf, value, strings.Join(choices, ", "))
-		}
-	}
-
-	return nil
-}
-
-func Uint16IsOneOf(port uint16, choices []uint16) (ok bool) {
-	for _, choice := range choices {
-		if port == choice {
-			return true
-		}
-	}
-	return false
-}

internal/configuration/settings/helpers/copy.go

@@ -1,199 +0,0 @@
-package helpers
-
-import (
-	"net"
-	"time"
-
-	"github.com/qdm12/log"
-	"inet.af/netaddr"
-)
-
-func CopyStringPtr(original *string) (copied *string) {
-	if original == nil {
-		return nil
-	}
-	copied = new(string)
-	*copied = *original
-	return copied
-}
-
-func CopyBoolPtr(original *bool) (copied *bool) {
-	if original == nil {
-		return nil
-	}
-	copied = new(bool)
-	*copied = *original
-	return copied
-}
-
-func CopyUint8Ptr(original *uint8) (copied *uint8) {
-	if original == nil {
-		return nil
-	}
-	copied = new(uint8)
-	*copied = *original
-	return copied
-}
-
-func CopyUint16Ptr(original *uint16) (copied *uint16) {
-	if original == nil {
-		return nil
-	}
-	copied = new(uint16)
-	*copied = *original
-	return copied
-}
-
-func CopyUint32Ptr(original *uint32) (copied *uint32) {
-	if original == nil {
-		return nil
-	}
-	copied = new(uint32)
-	*copied = *original
-	return copied
-}
-
-func CopyIntPtr(original *int) (copied *int) {
-	if original == nil {
-		return nil
-	}
-	copied = new(int)
-	*copied = *original
-	return copied
-}
-
-func CopyDurationPtr(original *time.Duration) (copied *time.Duration) {
-	if original == nil {
-		return nil
-	}
-	copied = new(time.Duration)
-	*copied = *original
-	return copied
-}
-
-func CopyLogLevelPtr(original *log.Level) (copied *log.Level) {
-	if original == nil {
-		return nil
-	}
-	copied = new(log.Level)
-	*copied = *original
-	return copied
-}
-
-func CopyIP(original net.IP) (copied net.IP) {
-	if original == nil {
-		return nil
-	}
-	copied = make(net.IP, len(original))
-	copy(copied, original)
-	return copied
-}
-
-func CopyIPNet(original net.IPNet) (copied net.IPNet) {
-	if original.IP != nil {
-		copied.IP = make(net.IP, len(original.IP))
-		copy(copied.IP, original.IP)
-	}
-
-	if original.Mask != nil {
-		copied.Mask = make(net.IPMask, len(original.Mask))
-		copy(copied.Mask, original.Mask)
-	}
-
-	return copied
-}
-
-func CopyIPNetPtr(original *net.IPNet) (copied *net.IPNet) {
-	if original == nil {
-		return nil
-	}
-
-	copied = new(net.IPNet)
-	*copied = CopyIPNet(*original)
-	return copied
-}
-
-func CopyNetaddrIP(original netaddr.IP) (copied netaddr.IP) {
-	b, err := original.MarshalBinary()
-	if err != nil {
-		panic(err)
-	}
-
-	err = copied.UnmarshalBinary(b)
-	if err != nil {
-		panic(err)
-	}
-
-	return copied
-}
-
-func CopyIPPrefix(original netaddr.IPPrefix) (copied netaddr.IPPrefix) {
-	b, err := original.MarshalText()
-	if err != nil {
-		panic(err)
-	}
-
-	err = copied.UnmarshalText(b)
-	if err != nil {
-		panic(err)
-	}
-
-	return copied
-}
-
-func CopyStringSlice(original []string) (copied []string) {
-	if original == nil {
-		return nil
-	}
-
-	copied = make([]string, len(original))
-	copy(copied, original)
-	return copied
-}
-
-func CopyUint16Slice(original []uint16) (copied []uint16) {
-	if original == nil {
-		return nil
-	}
-
-	copied = make([]uint16, len(original))
-	copy(copied, original)
-	return copied
-}
-
-func CopyIPNetSlice(original []net.IPNet) (copied []net.IPNet) {
-	if original == nil {
-		return nil
-	}
-
-	copied = make([]net.IPNet, len(original))
-	for i := range original {
-		copied[i] = CopyIPNet(original[i])
-	}
-	return copied
-}
-
-func CopyIPPrefixSlice(original []netaddr.IPPrefix) (copied []netaddr.IPPrefix) {
-	if original == nil {
-		return nil
-	}
-
-	copied = make([]netaddr.IPPrefix, len(original))
-	for i := range original {
-		copied[i] = CopyIPPrefix(original[i])
-	}
-	return copied
-}
-
-func CopyNetaddrIPsSlice(original []netaddr.IP) (copied []netaddr.IP) {
-	if original == nil {
-		return nil
-	}
-
-	copied = make([]netaddr.IP, len(original))
-	for i := range original {
-		copied[i] = CopyNetaddrIP(original[i])
-	}
-
-	return copied
-}

internal/configuration/settings/helpers/default.go

@@ -1,102 +0,0 @@
-package helpers
-
-import (
-	"net"
-	"time"
-
-	"github.com/qdm12/log"
-)
-
-func DefaultInt(existing *int, defaultValue int) (
-	result *int) {
-	if existing != nil {
-		return existing
-	}
-	result = new(int)
-	*result = defaultValue
-	return result
-}
-
-func DefaultUint8(existing *uint8, defaultValue uint8) (
-	result *uint8) {
-	if existing != nil {
-		return existing
-	}
-	result = new(uint8)
-	*result = defaultValue
-	return result
-}
-
-func DefaultUint16(existing *uint16, defaultValue uint16) (
-	result *uint16) {
-	if existing != nil {
-		return existing
-	}
-	result = new(uint16)
-	*result = defaultValue
-	return result
-}
-func DefaultUint32(existing *uint32, defaultValue uint32) (
-	result *uint32) {
-	if existing != nil {
-		return existing
-	}
-	result = new(uint32)
-	*result = defaultValue
-	return result
-}
-
-func DefaultBool(existing *bool, defaultValue bool) (
-	result *bool) {
-	if existing != nil {
-		return existing
-	}
-	result = new(bool)
-	*result = defaultValue
-	return result
-}
-
-func DefaultString(existing string, defaultValue string) (
-	result string) {
-	if existing != "" {
-		return existing
-	}
-	return defaultValue
-}
-
-func DefaultStringPtr(existing *string, defaultValue string) (result *string) {
-	if existing != nil {
-		return existing
-	}
-	result = new(string)
-	*result = defaultValue
-	return result
-}
-
-func DefaultDuration(existing *time.Duration,
-	defaultValue time.Duration) (result *time.Duration) {
-	if existing != nil {
-		return existing
-	}
-	result = new(time.Duration)
-	*result = defaultValue
-	return result
-}
-
-func DefaultLogLevel(existing *log.Level,
-	defaultValue log.Level) (result *log.Level) {
-	if existing != nil {
-		return existing
-	}
-	result = new(log.Level)
-	*result = defaultValue
-	return result
-}
-
-func DefaultIP(existing net.IP, defaultValue net.IP) (
-	result net.IP) {
-	if existing != nil {
-		return existing
-	}
-	return defaultValue
-}

internal/configuration/settings/helpers/files.go

@@ -1,31 +0,0 @@
-package helpers
-
-import (
-	"errors"
-	"fmt"
-	"os"
-	"path/filepath"
-)
-
-var (
-	ErrFileDoesNotExist = errors.New("file does not exist")
-	ErrFileRead         = errors.New("cannot read file")
-	ErrFileClose        = errors.New("cannot close file")
-)
-
-func FileExists(path string) (err error) {
-	path = filepath.Clean(path)
-
-	f, err := os.Open(path)
-	if errors.Is(err, os.ErrNotExist) {
-		return fmt.Errorf("%w: %s", ErrFileDoesNotExist, path)
-	} else if err != nil {
-		return fmt.Errorf("%w: %s", ErrFileRead, err)
-	}
-
-	if err := f.Close(); err != nil {
-		return fmt.Errorf("%w: %s", ErrFileClose, err)
-	}
-
-	return nil
-}

internal/configuration/settings/helpers/merge.go

@@ -1,259 +0,0 @@
-package helpers
-
-import (
-	"net"
-	"net/http"
-	"time"
-
-	"github.com/qdm12/log"
-	"inet.af/netaddr"
-)
-
-func MergeWithBool(existing, other *bool) (result *bool) {
-	if existing != nil {
-		return existing
-	} else if other == nil {
-		return nil
-	}
-	result = new(bool)
-	*result = *other
-	return result
-}
-
-func MergeWithString(existing, other string) (result string) {
-	if existing != "" {
-		return existing
-	}
-	return other
-}
-
-func MergeWithInt(existing, other int) (result int) {
-	if existing != 0 {
-		return existing
-	}
-	return other
-}
-
-func MergeWithFloat64(existing, other float64) (result float64) {
-	if existing != 0 {
-		return existing
-	}
-	return other
-}
-
-func MergeWithStringPtr(existing, other *string) (result *string) {
-	if existing != nil {
-		return existing
-	} else if other == nil {
-		return nil
-	}
-	result = new(string)
-	*result = *other
-	return result
-}
-
-func MergeWithIntPtr(existing, other *int) (result *int) {
-	if existing != nil {
-		return existing
-	} else if other == nil {
-		return nil
-	}
-	result = new(int)
-	*result = *other
-	return result
-}
-
-func MergeWithUint8(existing, other *uint8) (result *uint8) {
-	if existing != nil {
-		return existing
-	} else if other == nil {
-		return nil
-	}
-	result = new(uint8)
-	*result = *other
-	return result
-}
-
-func MergeWithUint16(existing, other *uint16) (result *uint16) {
-	if existing != nil {
-		return existing
-	} else if other == nil {
-		return nil
-	}
-	result = new(uint16)
-	*result = *other
-	return result
-}
-
-func MergeWithUint32(existing, other *uint32) (result *uint32) {
-	if existing != nil {
-		return existing
-	} else if other == nil {
-		return nil
-	}
-	result = new(uint32)
-	*result = *other
-	return result
-}
-
-func MergeWithIP(existing, other net.IP) (result net.IP) {
-	if existing != nil {
-		return existing
-	} else if other == nil {
-		return nil
-	}
-	result = make(net.IP, len(other))
-	copy(result, other)
-	return result
-}
-
-func MergeWithDuration(existing, other *time.Duration) (result *time.Duration) {
-	if existing != nil {
-		return existing
-	}
-	return other
-}
-
-func MergeWithLogLevel(existing, other *log.Level) (result *log.Level) {
-	if existing != nil {
-		return existing
-	} else if other == nil {
-		return nil
-	}
-	result = new(log.Level)
-	*result = *other
-	return result
-}
-
-func MergeWithHTTPHandler(existing, other http.Handler) (result http.Handler) {
-	if existing != nil {
-		return existing
-	}
-	return other
-}
-
-func MergeStringSlices(a, b []string) (result []string) {
-	if a == nil && b == nil {
-		return nil
-	}
-
-	seen := make(map[string]struct{}, len(a)+len(b))
-	result = make([]string, 0, len(a)+len(b))
-	for _, s := range a {
-		if _, ok := seen[s]; ok {
-			continue // duplicate
-		}
-		result = append(result, s)
-		seen[s] = struct{}{}
-	}
-	for _, s := range b {
-		if _, ok := seen[s]; ok {
-			continue // duplicate
-		}
-		result = append(result, s)
-		seen[s] = struct{}{}
-	}
-	return result
-}
-
-func MergeUint16Slices(a, b []uint16) (result []uint16) {
-	if a == nil && b == nil {
-		return nil
-	}
-
-	seen := make(map[uint16]struct{}, len(a)+len(b))
-	result = make([]uint16, 0, len(a)+len(b))
-	for _, n := range a {
-		if _, ok := seen[n]; ok {
-			continue // duplicate
-		}
-		result = append(result, n)
-		seen[n] = struct{}{}
-	}
-	for _, n := range b {
-		if _, ok := seen[n]; ok {
-			continue // duplicate
-		}
-		result = append(result, n)
-		seen[n] = struct{}{}
-	}
-	return result
-}
-
-func MergeIPNetsSlices(a, b []net.IPNet) (result []net.IPNet) {
-	if a == nil && b == nil {
-		return nil
-	}
-
-	seen := make(map[string]struct{}, len(a)+len(b))
-	result = make([]net.IPNet, 0, len(a)+len(b))
-	for _, ipNet := range a {
-		key := ipNet.String()
-		if _, ok := seen[key]; ok {
-			continue // duplicate
-		}
-		result = append(result, ipNet)
-		seen[key] = struct{}{}
-	}
-	for _, ipNet := range b {
-		key := ipNet.String()
-		if _, ok := seen[key]; ok {
-			continue // duplicate
-		}
-		result = append(result, ipNet)
-		seen[key] = struct{}{}
-	}
-	return result
-}
-
-func MergeNetaddrIPsSlices(a, b []netaddr.IP) (result []netaddr.IP) {
-	if a == nil && b == nil {
-		return nil
-	}
-
-	seen := make(map[string]struct{}, len(a)+len(b))
-	result = make([]netaddr.IP, 0, len(a)+len(b))
-	for _, ip := range a {
-		key := ip.String()
-		if _, ok := seen[key]; ok {
-			continue // duplicate
-		}
-		result = append(result, ip)
-		seen[key] = struct{}{}
-	}
-	for _, ip := range b {
-		key := ip.String()
-		if _, ok := seen[key]; ok {
-			continue // duplicate
-		}
-		result = append(result, ip)
-		seen[key] = struct{}{}
-	}
-	return result
-}
-
-func MergeIPPrefixesSlices(a, b []netaddr.IPPrefix) (result []netaddr.IPPrefix) {
-	if a == nil && b == nil {
-		return nil
-	}
-
-	seen := make(map[string]struct{}, len(a)+len(b))
-	result = make([]netaddr.IPPrefix, 0, len(a)+len(b))
-	for _, ipPrefix := range a {
-		key := ipPrefix.String()
-		if _, ok := seen[key]; ok {
-			continue // duplicate
-		}
-		result = append(result, ipPrefix)
-		seen[key] = struct{}{}
-	}
-	for _, ipPrefix := range b {
-		key := ipPrefix.String()
-		if _, ok := seen[key]; ok {
-			continue // duplicate
-		}
-		result = append(result, ipPrefix)
-		seen[key] = struct{}{}
-	}
-	return result
-}

internal/configuration/settings/helpers/messages.go

@@ -1,29 +0,0 @@
-package helpers
-
-import (
-	"fmt"
-	"strings"
-)
-
-func ChoicesOrString(choices []string) string {
-	return strings.Join(
-		choices[:len(choices)-1], ", ") +
-		" or " + choices[len(choices)-1]
-}
-
-func PortChoicesOrString(ports []uint16) (s string) {
-	switch len(ports) {
-	case 0:
-		return "there is no allowed port"
-	case 1:
-		return "allowed port is " + fmt.Sprint(ports[0])
-	}
-
-	s = "allowed ports are "
-	portStrings := make([]string, len(ports))
-	for i := range ports {
-		portStrings[i] = fmt.Sprint(ports[i])
-	}
-	s += ChoicesOrString(portStrings)
-	return s
-}

internal/configuration/settings/helpers/obfuscate.go

@@ -1,25 +0,0 @@
-package helpers
-
-func ObfuscateWireguardKey(fullKey string) (obfuscatedKey string) {
-	const minKeyLength = 10
-	if len(fullKey) < minKeyLength {
-		return "(too short)"
-	}
-
-	lastIndex := len(fullKey) - 1
-	return fullKey[0:2] + "..." + fullKey[lastIndex-2:]
-}
-
-func ObfuscatePassword(password string) (obfuscatedPassword string) {
-	if password != "" {
-		return "[set]"
-	}
-	return "[not set]"
-}
-
-func ObfuscateData(data string) (obfuscated string) {
-	if data != "" {
-		return "[set]"
-	}
-	return "[not set]"
-}

internal/configuration/settings/helpers/override.go

@@ -1,164 +0,0 @@
-package helpers
-
-import (
-	"net"
-	"net/http"
-	"time"
-
-	"github.com/qdm12/log"
-	"inet.af/netaddr"
-)
-
-func OverrideWithBool(existing, other *bool) (result *bool) {
-	if other == nil {
-		return existing
-	}
-	result = new(bool)
-	*result = *other
-	return result
-}
-
-func OverrideWithString(existing, other string) (result string) {
-	if other == "" {
-		return existing
-	}
-	return other
-}
-
-func OverrideWithInt(existing, other int) (result int) {
-	if other == 0 {
-		return existing
-	}
-	return other
-}
-
-func OverrideWithFloat64(existing, other float64) (result float64) {
-	if other == 0 {
-		return existing
-	}
-	return other
-}
-
-func OverrideWithStringPtr(existing, other *string) (result *string) {
-	if other == nil {
-		return existing
-	}
-	result = new(string)
-	*result = *other
-	return result
-}
-
-func OverrideWithIntPtr(existing, other *int) (result *int) {
-	if other == nil {
-		return existing
-	}
-	result = new(int)
-	*result = *other
-	return result
-}
-
-func OverrideWithUint8(existing, other *uint8) (result *uint8) {
-	if other == nil {
-		return existing
-	}
-	result = new(uint8)
-	*result = *other
-	return result
-}
-
-func OverrideWithUint16(existing, other *uint16) (result *uint16) {
-	if other == nil {
-		return existing
-	}
-	result = new(uint16)
-	*result = *other
-	return result
-}
-
-func OverrideWithUint32(existing, other *uint32) (result *uint32) {
-	if other == nil {
-		return existing
-	}
-	result = new(uint32)
-	*result = *other
-	return result
-}
-
-func OverrideWithIP(existing, other net.IP) (result net.IP) {
-	if other == nil {
-		return existing
-	}
-	result = make(net.IP, len(other))
-	copy(result, other)
-	return result
-}
-
-func OverrideWithDuration(existing, other *time.Duration) (result *time.Duration) {
-	if other == nil {
-		return existing
-	}
-	result = new(time.Duration)
-	*result = *other
-	return result
-}
-
-func OverrideWithLogLevel(existing, other *log.Level) (result *log.Level) {
-	if other == nil {
-		return existing
-	}
-	result = new(log.Level)
-	*result = *other
-	return result
-}
-
-func OverrideWithHTTPHandler(existing, other http.Handler) (result http.Handler) {
-	if other != nil {
-		return other
-	}
-	return existing
-}
-
-func OverrideWithStringSlice(existing, other []string) (result []string) {
-	if other == nil {
-		return existing
-	}
-	result = make([]string, len(other))
-	copy(result, other)
-	return result
-}
-
-func OverrideWithUint16Slice(existing, other []uint16) (result []uint16) {
-	if other == nil {
-		return existing
-	}
-	result = make([]uint16, len(other))
-	copy(result, other)
-	return result
-}
-
-func OverrideWithIPNetsSlice(existing, other []net.IPNet) (result []net.IPNet) {
-	if other == nil {
-		return existing
-	}
-	result = make([]net.IPNet, len(other))
-	copy(result, other)
-	return result
-}
-
-func OverrideWithNetaddrIPsSlice(existing, other []netaddr.IP) (result []netaddr.IP) {
-	if other == nil {
-		return existing
-	}
-	result = make([]netaddr.IP, len(other))
-	copy(result, other)
-	return result
-}
-
-func OverrideWithIPPrefixesSlice(existing, other []netaddr.IPPrefix) (result []netaddr.IPPrefix) {
-	if other == nil {
-		return existing
-	}
-	result = make([]netaddr.IPPrefix, len(other))
-	copy(result, other)
-	return result
-}

internal/configuration/settings/helpers/pointers.go

@@ -1,11 +0,0 @@
-package helpers
-
-import "time"
-
-// StringPtr returns a pointer to the string value
-// passed as argument.
-func StringPtr(s string) *string { return &s }
-
-// DurationPtr returns a pointer to the duration value
-// passed as argument.
-func DurationPtr(d time.Duration) *time.Duration { return &d }

internal/configuration/settings/helpers/string.go

@@ -1,12 +1,5 @@
 package helpers
 
-func BoolPtrToYesNo(b *bool) string {
-	if *b {
-		return "yes"
-	}
-	return "no"
-}
-
 func TCPPtrToString(tcp *bool) string {
 	if *tcp {
 		return "TCP"

internal/configuration/settings/httpproxy.go

@@ -3,8 +3,9 @@ package settings
 import (
 	"fmt"
 	"os"
+	"time"
 
-	"github.com/qdm12/gluetun/internal/configuration/settings/helpers"
+	"github.com/qdm12/gosettings"
 	"github.com/qdm12/gotree"
 	"github.com/qdm12/govalid/address"
 )
@@ -33,13 +34,19 @@ type HTTPProxy struct {
 	// each request/response. It cannot be nil in the
 	// internal state.
 	Log *bool
+	// ReadHeaderTimeout is the HTTP header read timeout duration
+	// of the HTTP server. It defaults to 1 second if left unset.
+	ReadHeaderTimeout time.Duration
+	// ReadTimeout is the HTTP read timeout duration
+	// of the HTTP server. It defaults to 3 seconds if left unset.
+	ReadTimeout time.Duration
 }
 
 func (h HTTPProxy) validate() (err error) {
 	// Do not validate user and password
 
 	uid := os.Getuid()
-	_, err = address.Validate(h.ListeningAddress, address.OptionListening(uid))
+	err = address.Validate(h.ListeningAddress, address.OptionListening(uid))
 	if err != nil {
 		return fmt.Errorf("%w: %s", ErrServerAddressNotValid, h.ListeningAddress)
 	}
@@ -49,45 +56,55 @@ func (h HTTPProxy) validate() (err error) {
 
 func (h *HTTPProxy) copy() (copied HTTPProxy) {
 	return HTTPProxy{
-		User:             helpers.CopyStringPtr(h.User),
-		Password:         helpers.CopyStringPtr(h.Password),
-		ListeningAddress: h.ListeningAddress,
-		Enabled:          helpers.CopyBoolPtr(h.Enabled),
-		Stealth:          helpers.CopyBoolPtr(h.Stealth),
-		Log:              helpers.CopyBoolPtr(h.Log),
+		User:              gosettings.CopyPointer(h.User),
+		Password:          gosettings.CopyPointer(h.Password),
+		ListeningAddress:  h.ListeningAddress,
+		Enabled:           gosettings.CopyPointer(h.Enabled),
+		Stealth:           gosettings.CopyPointer(h.Stealth),
+		Log:               gosettings.CopyPointer(h.Log),
+		ReadHeaderTimeout: h.ReadHeaderTimeout,
+		ReadTimeout:       h.ReadTimeout,
 	}
 }
 
 // mergeWith merges the other settings into any
 // unset field of the receiver settings object.
 func (h *HTTPProxy) mergeWith(other HTTPProxy) {
-	h.User = helpers.MergeWithStringPtr(h.User, other.User)
-	h.Password = helpers.MergeWithStringPtr(h.Password, other.Password)
-	h.ListeningAddress = helpers.MergeWithString(h.ListeningAddress, other.ListeningAddress)
-	h.Enabled = helpers.MergeWithBool(h.Enabled, other.Enabled)
-	h.Stealth = helpers.MergeWithBool(h.Stealth, other.Stealth)
-	h.Log = helpers.MergeWithBool(h.Log, other.Log)
+	h.User = gosettings.MergeWithPointer(h.User, other.User)
+	h.Password = gosettings.MergeWithPointer(h.Password, other.Password)
+	h.ListeningAddress = gosettings.MergeWithString(h.ListeningAddress, other.ListeningAddress)
+	h.Enabled = gosettings.MergeWithPointer(h.Enabled, other.Enabled)
+	h.Stealth = gosettings.MergeWithPointer(h.Stealth, other.Stealth)
+	h.Log = gosettings.MergeWithPointer(h.Log, other.Log)
+	h.ReadHeaderTimeout = gosettings.MergeWithNumber(h.ReadHeaderTimeout, other.ReadHeaderTimeout)
+	h.ReadTimeout = gosettings.MergeWithNumber(h.ReadTimeout, other.ReadTimeout)
 }
 
 // overrideWith overrides fields of the receiver
 // settings object with any field set in the other
 // settings.
 func (h *HTTPProxy) overrideWith(other HTTPProxy) {
-	h.User = helpers.OverrideWithStringPtr(h.User, other.User)
-	h.Password = helpers.OverrideWithStringPtr(h.Password, other.Password)
-	h.ListeningAddress = helpers.OverrideWithString(h.ListeningAddress, other.ListeningAddress)
-	h.Enabled = helpers.OverrideWithBool(h.Enabled, other.Enabled)
-	h.Stealth = helpers.OverrideWithBool(h.Stealth, other.Stealth)
-	h.Log = helpers.OverrideWithBool(h.Log, other.Log)
+	h.User = gosettings.OverrideWithPointer(h.User, other.User)
+	h.Password = gosettings.OverrideWithPointer(h.Password, other.Password)
+	h.ListeningAddress = gosettings.OverrideWithString(h.ListeningAddress, other.ListeningAddress)
+	h.Enabled = gosettings.OverrideWithPointer(h.Enabled, other.Enabled)
+	h.Stealth = gosettings.OverrideWithPointer(h.Stealth, other.Stealth)
+	h.Log = gosettings.OverrideWithPointer(h.Log, other.Log)
+	h.ReadHeaderTimeout = gosettings.OverrideWithNumber(h.ReadHeaderTimeout, other.ReadHeaderTimeout)
+	h.ReadTimeout = gosettings.OverrideWithNumber(h.ReadTimeout, other.ReadTimeout)
 }
 
 func (h *HTTPProxy) setDefaults() {
-	h.User = helpers.DefaultStringPtr(h.User, "")
-	h.Password = helpers.DefaultStringPtr(h.Password, "")
-	h.ListeningAddress = helpers.DefaultString(h.ListeningAddress, ":8888")
-	h.Enabled = helpers.DefaultBool(h.Enabled, false)
-	h.Stealth = helpers.DefaultBool(h.Stealth, false)
-	h.Log = helpers.DefaultBool(h.Log, false)
+	h.User = gosettings.DefaultPointer(h.User, "")
+	h.Password = gosettings.DefaultPointer(h.Password, "")
+	h.ListeningAddress = gosettings.DefaultString(h.ListeningAddress, ":8888")
+	h.Enabled = gosettings.DefaultPointer(h.Enabled, false)
+	h.Stealth = gosettings.DefaultPointer(h.Stealth, false)
+	h.Log = gosettings.DefaultPointer(h.Log, false)
+	const defaultReadHeaderTimeout = time.Second
+	h.ReadHeaderTimeout = gosettings.DefaultNumber(h.ReadHeaderTimeout, defaultReadHeaderTimeout)
+	const defaultReadTimeout = 3 * time.Second
+	h.ReadTimeout = gosettings.DefaultNumber(h.ReadTimeout, defaultReadTimeout)
 }
 
 func (h HTTPProxy) String() string {
@@ -96,16 +113,18 @@ func (h HTTPProxy) String() string {
 
 func (h HTTPProxy) toLinesNode() (node *gotree.Node) {
 	node = gotree.New("HTTP proxy settings:")
-	node.Appendf("Enabled: %s", helpers.BoolPtrToYesNo(h.Enabled))
+	node.Appendf("Enabled: %s", gosettings.BoolToYesNo(h.Enabled))
 	if !*h.Enabled {
 		return node
 	}
 
 	node.Appendf("Listening address: %s", h.ListeningAddress)
 	node.Appendf("User: %s", *h.User)
-	node.Appendf("Password: %s", helpers.ObfuscatePassword(*h.Password))
-	node.Appendf("Stealth mode: %s", helpers.BoolPtrToYesNo(h.Stealth))
-	node.Appendf("Log: %s", helpers.BoolPtrToYesNo(h.Log))
+	node.Appendf("Password: %s", gosettings.ObfuscateKey(*h.Password))
+	node.Appendf("Stealth mode: %s", gosettings.BoolToYesNo(h.Stealth))
+	node.Appendf("Log: %s", gosettings.BoolToYesNo(h.Log))
+	node.Appendf("Read header timeout: %s", h.ReadHeaderTimeout)
+	node.Appendf("Read timeout: %s", h.ReadTimeout)
 
 	return node
 }

internal/configuration/settings/log.go

@@ -1,7 +1,7 @@
 package settings
 
 import (
-	"github.com/qdm12/gluetun/internal/configuration/settings/helpers"
+	"github.com/qdm12/gosettings"
 	"github.com/qdm12/gotree"
 	"github.com/qdm12/log"
 )
@@ -19,25 +19,25 @@ func (l Log) validate() (err error) {
 
 func (l *Log) copy() (copied Log) {
 	return Log{
-		Level: helpers.CopyLogLevelPtr(l.Level),
+		Level: gosettings.CopyPointer(l.Level),
 	}
 }
 
 // mergeWith merges the other settings into any
 // unset field of the receiver settings object.
 func (l *Log) mergeWith(other Log) {
-	l.Level = helpers.MergeWithLogLevel(l.Level, other.Level)
+	l.Level = gosettings.MergeWithPointer(l.Level, other.Level)
 }
 
 // overrideWith overrides fields of the receiver
 // settings object with any field set in the other
 // settings.
 func (l *Log) overrideWith(other Log) {
-	l.Level = helpers.OverrideWithLogLevel(l.Level, other.Level)
+	l.Level = gosettings.OverrideWithPointer(l.Level, other.Level)
 }
 
 func (l *Log) setDefaults() {
-	l.Level = helpers.DefaultLogLevel(l.Level, log.LevelInfo)
+	l.Level = gosettings.DefaultPointer(l.Level, log.LevelInfo)
 }
 
 func (l Log) String() string {

internal/configuration/settings/netaddr.go

@@ -0,0 +1,36 @@
+package settings
+
+import (
+	"net/netip"
+
+	"inet.af/netaddr"
+)
+
+func netipAddressToNetaddrIP(address netip.Addr) (ip netaddr.IP) {
+	if address.Is4() {
+		return netaddr.IPFrom4(address.As4())
+	}
+	return netaddr.IPFrom16(address.As16())
+}
+
+func netipAddressesToNetaddrIPs(addresses []netip.Addr) (ips []netaddr.IP) {
+	ips = make([]netaddr.IP, len(addresses))
+	for i := range addresses {
+		ips[i] = netipAddressToNetaddrIP(addresses[i])
+	}
+	return ips
+}
+
+func netipPrefixToNetaddrIPPrefix(prefix netip.Prefix) (ipPrefix netaddr.IPPrefix) {
+	netaddrIP := netipAddressToNetaddrIP(prefix.Addr())
+	bits := prefix.Bits()
+	return netaddr.IPPrefixFrom(netaddrIP, uint8(bits))
+}
+
+func netipPrefixesToNetaddrIPPrefixes(prefixes []netip.Prefix) (ipPrefixes []netaddr.IPPrefix) {
+	ipPrefixes = make([]netaddr.IPPrefix, len(prefixes))
+	for i := range ipPrefixes {
+		ipPrefixes[i] = netipPrefixToNetaddrIPPrefix(prefixes[i])
+	}
+	return ipPrefixes
+}

internal/configuration/settings/nordvpn_retro.go

@@ -0,0 +1,42 @@
+package settings
+
+// Retro-compatibility because SERVER_REGIONS changed to SERVER_COUNTRIES
+// and SERVER_REGIONS is now the continent field for servers.
+// TODO v4 remove.
+func nordvpnRetroRegion(selection ServerSelection, validRegions, validCountries []string) (
+	updatedSelection ServerSelection) {
+	validRegionsMap := stringSliceToMap(validRegions)
+	validCountriesMap := stringSliceToMap(validCountries)
+
+	updatedSelection = selection.copy()
+	updatedSelection.Regions = make([]string, 0, len(selection.Regions))
+	for _, region := range selection.Regions {
+		_, isValid := validRegionsMap[region]
+		if isValid {
+			updatedSelection.Regions = append(updatedSelection.Regions, region)
+			continue
+		}
+
+		_, isValid = validCountriesMap[region]
+		if !isValid {
+			// Region is not valid for the country or region
+			// just leave it to the validation to fail it later
+			continue
+		}
+
+		// Region is not valid for a region, but is a valid country
+		// Handle retro-compatibility and transfer the value to the
+		// country field.
+		updatedSelection.Countries = append(updatedSelection.Countries, region)
+	}
+
+	return updatedSelection
+}
+
+func stringSliceToMap(slice []string) (m map[string]struct{}) {
+	m = make(map[string]struct{}, len(slice))
+	for _, s := range slice {
+		m[s] = struct{}{}
+	}
+	return m
+}

internal/configuration/settings/openvpn.go

@@ -4,100 +4,109 @@ import (
 	"encoding/base64"
 	"fmt"
 	"regexp"
-	"strings"
 
-	"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/openvpn/extract"
 	"github.com/qdm12/gluetun/internal/provider/privateinternetaccess/presets"
+	"github.com/qdm12/gosettings"
+	"github.com/qdm12/gosettings/validate"
 	"github.com/qdm12/gotree"
 )
 
 // OpenVPN contains settings to configure the OpenVPN client.
 type OpenVPN struct {
 	// Version is the OpenVPN version to run.
-	// It can only be "2.4" or "2.5".
-	Version string
+	// It can only be "2.5" or "2.6".
+	Version string `json:"version"`
 	// User is the OpenVPN authentication username.
-	// It cannot be an empty string in the internal state
-	// if OpenVPN is used.
-	User string
+	// It cannot be nil in the internal state if OpenVPN is used.
+	// It is usually required but in some cases can be the empty string
+	// to indicate no user+password authentication is needed.
+	User *string `json:"user"`
 	// Password is the OpenVPN authentication password.
-	// It cannot be an empty string in the internal state
-	// if OpenVPN is used.
-	Password string
+	// It cannot be nil in the internal state if OpenVPN is used.
+	// It is usually required but in some cases can be the empty string
+	// to indicate no user+password authentication is needed.
+	Password *string `json:"password"`
 	// ConfFile is a custom OpenVPN configuration file path.
 	// It can be set to the empty string for it to be ignored.
 	// It cannot be nil in the internal state.
-	ConfFile *string
+	ConfFile *string `json:"config_file_path"`
 	// Ciphers is a list of ciphers to use for OpenVPN,
 	// different from the ones specified by the VPN
 	// service provider configuration files.
-	Ciphers []string
+	Ciphers []string `json:"ciphers"`
 	// Auth is an auth algorithm to use in OpenVPN instead
 	// of the one specified by the VPN service provider.
 	// It cannot be nil in the internal state.
 	// It is ignored if it is set to the empty string.
-	Auth *string
-	// ClientCrt is the OpenVPN client certificate.
-	// This is notably used by Cyberghost.
+	Auth *string `json:"auth"`
+	// 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.
-	ClientCrt *string
-	// ClientKey is the OpenVPN client key.
+	Cert *string `json:"cert"`
+	// 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.
-	ClientKey *string
+	Key *string `json:"key"`
+	// 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 `json:"encrypted_key"`
+	// KeyPassphrase is the key passphrase to be used by OpenVPN
+	// to decrypt the EncryptedPrivateKey. It defaults to the
+	// empty string and must be set if EncryptedPrivateKey is set.
+	KeyPassphrase *string `json:"key_passphrase"`
 	// PIAEncPreset is the encryption preset for
 	// 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
+	PIAEncPreset *string `json:"pia_encryption_preset"`
 	// 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.
-	MSSFix *uint16
+	MSSFix *uint16 `json:"mssfix"`
 	// Interface is the OpenVPN device interface name.
 	// It cannot be an empty string in the internal state.
-	Interface string
+	Interface string `json:"interface"`
 	// ProcessUser is the OpenVPN process OS username
 	// to use. It cannot be empty in the internal state.
 	// It defaults to 'root'.
-	ProcessUser string
+	ProcessUser string `json:"process_user"`
 	// Verbosity is the OpenVPN verbosity level from 0 to 6.
 	// It cannot be nil in the internal state.
-	Verbosity *int
+	Verbosity *int `json:"verbosity"`
 	// Flags is a slice of additional flags to be passed
 	// to the OpenVPN program.
-	Flags []string
+	Flags []string `json:"flags"`
 }
 
 var ivpnAccountID = regexp.MustCompile(`^(i|ivpn)\-[a-zA-Z0-9]{4}\-[a-zA-Z0-9]{4}\-[a-zA-Z0-9]{4}$`)
 
 func (o OpenVPN) validate(vpnProvider string) (err error) {
 	// Validate version
-	validVersions := []string{openvpn.Openvpn24, openvpn.Openvpn25}
-	if !helpers.IsOneOf(o.Version, validVersions...) {
-		return fmt.Errorf("%w: %q can only be one of %s",
-			ErrOpenVPNVersionIsNotValid, o.Version, strings.Join(validVersions, ", "))
+	validVersions := []string{openvpn.Openvpn25, openvpn.Openvpn26}
+	if err = validate.IsOneOf(o.Version, validVersions...); err != nil {
+		return fmt.Errorf("%w: %w", ErrOpenVPNVersionIsNotValid, err)
 	}
 
 	isCustom := vpnProvider == providers.Custom
+	isUserRequired := !isCustom &&
+		vpnProvider != providers.Airvpn &&
+		vpnProvider != providers.VPNSecure
 
-	if !isCustom && o.User == "" {
-		return ErrOpenVPNUserIsEmpty
+	if isUserRequired && *o.User == "" {
+		return fmt.Errorf("%w", ErrOpenVPNUserIsEmpty)
 	}
 
-	passwordRequired := !isCustom &&
-		(vpnProvider != providers.Ivpn || !ivpnAccountID.MatchString(o.User))
+	passwordRequired := isUserRequired &&
+		(vpnProvider != providers.Ivpn || !ivpnAccountID.MatchString(*o.User))
 
-	if passwordRequired && o.Password == "" {
-		return ErrOpenVPNPasswordIsEmpty
+	if passwordRequired && *o.Password == "" {
+		return fmt.Errorf("%w", ErrOpenVPNPasswordIsEmpty)
 	}
 
 	err = validateOpenVPNConfigFilepath(isCustom, *o.ConfFile)
@@ -105,16 +114,25 @@ func (o OpenVPN) validate(vpnProvider string) (err error) {
 		return fmt.Errorf("custom configuration file: %w", err)
 	}
 
-	err = validateOpenVPNClientCertificate(vpnProvider, *o.ClientCrt)
+	err = validateOpenVPNClientCertificate(vpnProvider, *o.Cert)
 	if err != nil {
 		return fmt.Errorf("client certificate: %w", err)
 	}
 
-	err = validateOpenVPNClientKey(vpnProvider, *o.ClientKey)
+	err = validateOpenVPNClientKey(vpnProvider, *o.Key)
 	if err != nil {
 		return fmt.Errorf("client key: %w", err)
 	}
 
+	err = validateOpenVPNEncryptedKey(vpnProvider, *o.EncryptedKey)
+	if err != nil {
+		return fmt.Errorf("encrypted key: %w", err)
+	}
+
+	if *o.EncryptedKey != "" && *o.KeyPassphrase == "" {
+		return fmt.Errorf("%w", ErrOpenVPNKeyPassphraseIsEmpty)
+	}
+
 	const maxMSSFix = 10000
 	if *o.MSSFix > maxMSSFix {
 		return fmt.Errorf("%w: %d is over the maximum value of %d",
@@ -141,10 +159,10 @@ func validateOpenVPNConfigFilepath(isCustom bool,
 	}
 
 	if confFile == "" {
-		return ErrFilepathMissing
+		return fmt.Errorf("%w", ErrFilepathMissing)
 	}
 
-	err = helpers.FileExists(confFile)
+	err = validate.FileExists(confFile)
 	if err != nil {
 		return err
 	}
@@ -152,7 +170,7 @@ 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
@@ -162,10 +180,12 @@ func validateOpenVPNClientCertificate(vpnProvider,
 	clientCert string) (err error) {
 	switch vpnProvider {
 	case
+		providers.Airvpn,
 		providers.Cyberghost,
+		providers.VPNSecure,
 		providers.VPNUnlimited:
 		if clientCert == "" {
-			return ErrMissingValue
+			return fmt.Errorf("%w", ErrMissingValue)
 		}
 	}
 
@@ -183,11 +203,12 @@ func validateOpenVPNClientCertificate(vpnProvider,
 func validateOpenVPNClientKey(vpnProvider, clientKey string) (err error) {
 	switch vpnProvider {
 	case
+		providers.Airvpn,
 		providers.Cyberghost,
 		providers.VPNUnlimited,
 		providers.Wevpn:
 		if clientKey == "" {
-			return ErrMissingValue
+			return fmt.Errorf("%w", ErrMissingValue)
 		}
 	}
 
@@ -202,89 +223,112 @@ func validateOpenVPNClientKey(vpnProvider, clientKey string) (err error) {
 	return nil
 }
 
+func validateOpenVPNEncryptedKey(vpnProvider,
+	encryptedPrivateKey string) (err error) {
+	if vpnProvider == providers.VPNSecure && encryptedPrivateKey == "" {
+		return fmt.Errorf("%w", ErrMissingValue)
+	}
+
+	if encryptedPrivateKey == "" {
+		return nil
+	}
+
+	_, err = base64.StdEncoding.DecodeString(encryptedPrivateKey)
+	if err != nil {
+		return err
+	}
+	return nil
+}
+
 func (o *OpenVPN) copy() (copied OpenVPN) {
 	return OpenVPN{
-		Version:      o.Version,
-		User:         o.User,
-		Password:     o.Password,
-		ConfFile:     helpers.CopyStringPtr(o.ConfFile),
-		Ciphers:      helpers.CopyStringSlice(o.Ciphers),
-		Auth:         helpers.CopyStringPtr(o.Auth),
-		ClientCrt:    helpers.CopyStringPtr(o.ClientCrt),
-		ClientKey:    helpers.CopyStringPtr(o.ClientKey),
-		PIAEncPreset: helpers.CopyStringPtr(o.PIAEncPreset),
-		IPv6:         helpers.CopyBoolPtr(o.IPv6),
-		MSSFix:       helpers.CopyUint16Ptr(o.MSSFix),
-		Interface:    o.Interface,
-		ProcessUser:  o.ProcessUser,
-		Verbosity:    helpers.CopyIntPtr(o.Verbosity),
-		Flags:        helpers.CopyStringSlice(o.Flags),
+		Version:       o.Version,
+		User:          gosettings.CopyPointer(o.User),
+		Password:      gosettings.CopyPointer(o.Password),
+		ConfFile:      gosettings.CopyPointer(o.ConfFile),
+		Ciphers:       gosettings.CopySlice(o.Ciphers),
+		Auth:          gosettings.CopyPointer(o.Auth),
+		Cert:          gosettings.CopyPointer(o.Cert),
+		Key:           gosettings.CopyPointer(o.Key),
+		EncryptedKey:  gosettings.CopyPointer(o.EncryptedKey),
+		KeyPassphrase: gosettings.CopyPointer(o.KeyPassphrase),
+		PIAEncPreset:  gosettings.CopyPointer(o.PIAEncPreset),
+		MSSFix:        gosettings.CopyPointer(o.MSSFix),
+		Interface:     o.Interface,
+		ProcessUser:   o.ProcessUser,
+		Verbosity:     gosettings.CopyPointer(o.Verbosity),
+		Flags:         gosettings.CopySlice(o.Flags),
 	}
 }
 
 // mergeWith merges the other settings into any
 // unset field of the receiver settings object.
 func (o *OpenVPN) mergeWith(other OpenVPN) {
-	o.Version = helpers.MergeWithString(o.Version, other.Version)
-	o.User = helpers.MergeWithString(o.User, other.User)
-	o.Password = helpers.MergeWithString(o.Password, other.Password)
-	o.ConfFile = helpers.MergeWithStringPtr(o.ConfFile, other.ConfFile)
-	o.Ciphers = helpers.MergeStringSlices(o.Ciphers, other.Ciphers)
-	o.Auth = helpers.MergeWithStringPtr(o.Auth, other.Auth)
-	o.ClientCrt = helpers.MergeWithStringPtr(o.ClientCrt, other.ClientCrt)
-	o.ClientKey = helpers.MergeWithStringPtr(o.ClientKey, other.ClientKey)
-	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)
-	o.Verbosity = helpers.MergeWithIntPtr(o.Verbosity, other.Verbosity)
-	o.Flags = helpers.MergeStringSlices(o.Flags, other.Flags)
+	o.Version = gosettings.MergeWithString(o.Version, other.Version)
+	o.User = gosettings.MergeWithPointer(o.User, other.User)
+	o.Password = gosettings.MergeWithPointer(o.Password, other.Password)
+	o.ConfFile = gosettings.MergeWithPointer(o.ConfFile, other.ConfFile)
+	o.Ciphers = gosettings.MergeWithSlice(o.Ciphers, other.Ciphers)
+	o.Auth = gosettings.MergeWithPointer(o.Auth, other.Auth)
+	o.Cert = gosettings.MergeWithPointer(o.Cert, other.Cert)
+	o.Key = gosettings.MergeWithPointer(o.Key, other.Key)
+	o.EncryptedKey = gosettings.MergeWithPointer(o.EncryptedKey, other.EncryptedKey)
+	o.KeyPassphrase = gosettings.MergeWithPointer(o.KeyPassphrase, other.KeyPassphrase)
+	o.PIAEncPreset = gosettings.MergeWithPointer(o.PIAEncPreset, other.PIAEncPreset)
+	o.MSSFix = gosettings.MergeWithPointer(o.MSSFix, other.MSSFix)
+	o.Interface = gosettings.MergeWithString(o.Interface, other.Interface)
+	o.ProcessUser = gosettings.MergeWithString(o.ProcessUser, other.ProcessUser)
+	o.Verbosity = gosettings.MergeWithPointer(o.Verbosity, other.Verbosity)
+	o.Flags = gosettings.MergeWithSlice(o.Flags, other.Flags)
 }
 
 // overrideWith overrides fields of the receiver
 // settings object with any field set in the other
 // settings.
 func (o *OpenVPN) overrideWith(other OpenVPN) {
-	o.Version = helpers.OverrideWithString(o.Version, other.Version)
-	o.User = helpers.OverrideWithString(o.User, other.User)
-	o.Password = helpers.OverrideWithString(o.Password, other.Password)
-	o.ConfFile = helpers.OverrideWithStringPtr(o.ConfFile, other.ConfFile)
-	o.Ciphers = helpers.OverrideWithStringSlice(o.Ciphers, other.Ciphers)
-	o.Auth = helpers.OverrideWithStringPtr(o.Auth, other.Auth)
-	o.ClientCrt = helpers.OverrideWithStringPtr(o.ClientCrt, other.ClientCrt)
-	o.ClientKey = helpers.OverrideWithStringPtr(o.ClientKey, other.ClientKey)
-	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)
-	o.Verbosity = helpers.OverrideWithIntPtr(o.Verbosity, other.Verbosity)
-	o.Flags = helpers.OverrideWithStringSlice(o.Flags, other.Flags)
+	o.Version = gosettings.OverrideWithString(o.Version, other.Version)
+	o.User = gosettings.OverrideWithPointer(o.User, other.User)
+	o.Password = gosettings.OverrideWithPointer(o.Password, other.Password)
+	o.ConfFile = gosettings.OverrideWithPointer(o.ConfFile, other.ConfFile)
+	o.Ciphers = gosettings.OverrideWithSlice(o.Ciphers, other.Ciphers)
+	o.Auth = gosettings.OverrideWithPointer(o.Auth, other.Auth)
+	o.Cert = gosettings.OverrideWithPointer(o.Cert, other.Cert)
+	o.Key = gosettings.OverrideWithPointer(o.Key, other.Key)
+	o.EncryptedKey = gosettings.OverrideWithPointer(o.EncryptedKey, other.EncryptedKey)
+	o.KeyPassphrase = gosettings.OverrideWithPointer(o.KeyPassphrase, other.KeyPassphrase)
+	o.PIAEncPreset = gosettings.OverrideWithPointer(o.PIAEncPreset, other.PIAEncPreset)
+	o.MSSFix = gosettings.OverrideWithPointer(o.MSSFix, other.MSSFix)
+	o.Interface = gosettings.OverrideWithString(o.Interface, other.Interface)
+	o.ProcessUser = gosettings.OverrideWithString(o.ProcessUser, other.ProcessUser)
+	o.Verbosity = gosettings.OverrideWithPointer(o.Verbosity, other.Verbosity)
+	o.Flags = gosettings.OverrideWithSlice(o.Flags, other.Flags)
 }
 
 func (o *OpenVPN) setDefaults(vpnProvider string) {
-	o.Version = helpers.DefaultString(o.Version, openvpn.Openvpn25)
+	o.Version = gosettings.DefaultString(o.Version, openvpn.Openvpn25)
+	o.User = gosettings.DefaultPointer(o.User, "")
 	if vpnProvider == providers.Mullvad {
-		o.Password = "m"
+		o.Password = gosettings.DefaultPointer(o.Password, "m")
+	} else {
+		o.Password = gosettings.DefaultPointer(o.Password, "")
 	}
 
-	o.ConfFile = helpers.DefaultStringPtr(o.ConfFile, "")
-	o.Auth = helpers.DefaultStringPtr(o.Auth, "")
-	o.ClientCrt = helpers.DefaultStringPtr(o.ClientCrt, "")
-	o.ClientKey = helpers.DefaultStringPtr(o.ClientKey, "")
+	o.ConfFile = gosettings.DefaultPointer(o.ConfFile, "")
+	o.Auth = gosettings.DefaultPointer(o.Auth, "")
+	o.Cert = gosettings.DefaultPointer(o.Cert, "")
+	o.Key = gosettings.DefaultPointer(o.Key, "")
+	o.EncryptedKey = gosettings.DefaultPointer(o.EncryptedKey, "")
+	o.KeyPassphrase = gosettings.DefaultPointer(o.KeyPassphrase, "")
 
 	var defaultEncPreset string
 	if vpnProvider == providers.PrivateInternetAccess {
 		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")
-	o.Verbosity = helpers.DefaultInt(o.Verbosity, 1)
+	o.PIAEncPreset = gosettings.DefaultPointer(o.PIAEncPreset, defaultEncPreset)
+	o.MSSFix = gosettings.DefaultPointer(o.MSSFix, 0)
+	o.Interface = gosettings.DefaultString(o.Interface, "tun0")
+	o.ProcessUser = gosettings.DefaultString(o.ProcessUser, "root")
+	o.Verbosity = gosettings.DefaultPointer(o.Verbosity, 1)
 }
 
 func (o OpenVPN) String() string {
@@ -294,8 +338,8 @@ func (o OpenVPN) String() string {
 func (o OpenVPN) toLinesNode() (node *gotree.Node) {
 	node = gotree.New("OpenVPN settings:")
 	node.Appendf("OpenVPN version: %s", o.Version)
-	node.Appendf("User: %s", helpers.ObfuscatePassword(o.User))
-	node.Appendf("Password: %s", helpers.ObfuscatePassword(o.Password))
+	node.Appendf("User: %s", gosettings.ObfuscateKey(*o.User))
+	node.Appendf("Password: %s", gosettings.ObfuscateKey(*o.Password))
 
 	if *o.ConfFile != "" {
 		node.Appendf("Custom configuration file: %s", *o.ConfFile)
@@ -309,20 +353,23 @@ func (o OpenVPN) toLinesNode() (node *gotree.Node) {
 		node.Appendf("Auth: %s", *o.Auth)
 	}
 
-	if *o.ClientCrt != "" {
-		node.Appendf("Client crt: %s", helpers.ObfuscateData(*o.ClientCrt))
+	if *o.Cert != "" {
+		node.Appendf("Client crt: %s", gosettings.ObfuscateKey(*o.Cert))
 	}
 
-	if *o.ClientKey != "" {
-		node.Appendf("Client key: %s", helpers.ObfuscateData(*o.ClientKey))
+	if *o.Key != "" {
+		node.Appendf("Client key: %s", gosettings.ObfuscateKey(*o.Key))
+	}
+
+	if *o.EncryptedKey != "" {
+		node.Appendf("Encrypted key: %s (key passhrapse %s)",
+			gosettings.ObfuscateKey(*o.EncryptedKey), gosettings.ObfuscateKey(*o.KeyPassphrase))
 	}
 
 	if *o.PIAEncPreset != "" {
 		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

@@ -6,6 +6,8 @@ import (
 	"github.com/qdm12/gluetun/internal/configuration/settings/helpers"
 	"github.com/qdm12/gluetun/internal/constants/providers"
 	"github.com/qdm12/gluetun/internal/provider/privateinternetaccess/presets"
+	"github.com/qdm12/gosettings"
+	"github.com/qdm12/gosettings/validate"
 	"github.com/qdm12/gotree"
 )
 
@@ -14,25 +16,25 @@ type OpenVPNSelection struct {
 	// It can be set to an empty string to indicate to
 	// NOT use a custom configuration file.
 	// It cannot be nil in the internal state.
-	ConfFile *string
+	ConfFile *string `json:"config_file_path"`
 	// TCP is true if the OpenVPN protocol is TCP,
 	// and false for UDP.
 	// It cannot be nil in the internal state.
-	TCP *bool
+	TCP *bool `json:"tcp"`
 	// CustomPort is the OpenVPN server endpoint port.
 	// It can be set to 0 to indicate no custom port should
 	// be used. It cannot be nil in the internal state.
-	CustomPort *uint16 // HideMyAss, Mullvad, PIA, ProtonVPN, WeVPN, Windscribe
+	CustomPort *uint16 `json:"custom_port"`
 	// PIAEncPreset is the encryption preset for
 	// Private Internet Access. It can be set to an
 	// empty string for other providers.
-	PIAEncPreset *string
+	PIAEncPreset *string `json:"pia_encryption_preset"`
 }
 
 func (o OpenVPNSelection) validate(vpnProvider string) (err error) {
 	// Validate ConfFile
 	if confFile := *o.ConfFile; confFile != "" {
-		err := helpers.FileExists(confFile)
+		err := validate.FileExists(confFile)
 		if err != nil {
 			return fmt.Errorf("configuration file: %w", err)
 		}
@@ -54,19 +56,25 @@ func (o OpenVPNSelection) validate(vpnProvider string) (err error) {
 	if *o.CustomPort != 0 {
 		switch vpnProvider {
 		// no restriction on port
-		case providers.Cyberghost, providers.HideMyAss,
+		case providers.Custom, providers.Cyberghost, providers.HideMyAss,
 			providers.Privatevpn, providers.Torguard:
 		// no custom port allowed
 		case providers.Expressvpn, providers.Fastestvpn,
 			providers.Ipvanish, providers.Nordvpn,
 			providers.Privado, providers.Purevpn,
-			providers.Surfshark, providers.VPNUnlimited,
-			providers.Vyprvpn:
+			providers.Surfshark, providers.VPNSecure,
+			providers.VPNUnlimited, providers.Vyprvpn:
 			return fmt.Errorf("%w: for VPN service provider %s",
 				ErrOpenVPNCustomPortNotAllowed, vpnProvider)
 		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}
@@ -82,22 +90,27 @@ func (o OpenVPNSelection) validate(vpnProvider string) (err error) {
 			case providers.Protonvpn:
 				allowedTCP = []uint16{443, 5995, 8443}
 				allowedUDP = []uint16{80, 443, 1194, 4569, 5060}
+			case providers.SlickVPN:
+				allowedTCP = []uint16{443, 8080, 8888}
+				allowedUDP = []uint16{443, 8080, 8888}
 			case providers.Wevpn:
 				allowedTCP = []uint16{53, 1195, 1199, 2018}
 				allowedUDP = []uint16{80, 1194, 1198}
 			case providers.Windscribe:
 				allowedTCP = []uint16{21, 22, 80, 123, 143, 443, 587, 1194, 3306, 8080, 54783}
 				allowedUDP = []uint16{53, 80, 123, 443, 1194, 54783}
+			default:
+				panic(fmt.Sprintf("VPN provider %s has no registered allowed ports", vpnProvider))
 			}
 
-			if *o.TCP && !helpers.Uint16IsOneOf(*o.CustomPort, allowedTCP) {
-				return fmt.Errorf("%w: %d for VPN service provider %s; %s",
-					ErrOpenVPNCustomPortNotAllowed, o.CustomPort, vpnProvider,
-					helpers.PortChoicesOrString(allowedTCP))
-			} else if !*o.TCP && !helpers.Uint16IsOneOf(*o.CustomPort, allowedUDP) {
-				return fmt.Errorf("%w: %d for VPN service provider %s; %s",
-					ErrOpenVPNCustomPortNotAllowed, o.CustomPort, vpnProvider,
-					helpers.PortChoicesOrString(allowedUDP))
+			allowedPorts := allowedUDP
+			if *o.TCP {
+				allowedPorts = allowedTCP
+			}
+			err = validate.IsOneOf(*o.CustomPort, allowedPorts...)
+			if err != nil {
+				return fmt.Errorf("%w: for VPN service provider %s: %w",
+					ErrOpenVPNCustomPortNotAllowed, vpnProvider, err)
 			}
 		}
 	}
@@ -109,10 +122,8 @@ func (o OpenVPNSelection) validate(vpnProvider string) (err error) {
 			presets.Normal,
 			presets.Strong,
 		}
-		if !helpers.IsOneOf(*o.PIAEncPreset, validEncryptionPresets...) {
-			return fmt.Errorf("%w: %s; valid presets are %s",
-				ErrOpenVPNEncryptionPresetNotValid, *o.PIAEncPreset,
-				helpers.ChoicesOrString(validEncryptionPresets))
+		if err = validate.IsOneOf(*o.PIAEncPreset, validEncryptionPresets...); err != nil {
+			return fmt.Errorf("%w: %w", ErrOpenVPNEncryptionPresetNotValid, err)
 		}
 	}
 
@@ -121,37 +132,37 @@ func (o OpenVPNSelection) validate(vpnProvider string) (err error) {
 
 func (o *OpenVPNSelection) copy() (copied OpenVPNSelection) {
 	return OpenVPNSelection{
-		ConfFile:     helpers.CopyStringPtr(o.ConfFile),
-		TCP:          helpers.CopyBoolPtr(o.TCP),
-		CustomPort:   helpers.CopyUint16Ptr(o.CustomPort),
-		PIAEncPreset: helpers.CopyStringPtr(o.PIAEncPreset),
+		ConfFile:     gosettings.CopyPointer(o.ConfFile),
+		TCP:          gosettings.CopyPointer(o.TCP),
+		CustomPort:   gosettings.CopyPointer(o.CustomPort),
+		PIAEncPreset: gosettings.CopyPointer(o.PIAEncPreset),
 	}
 }
 
 func (o *OpenVPNSelection) mergeWith(other OpenVPNSelection) {
-	o.ConfFile = helpers.MergeWithStringPtr(o.ConfFile, other.ConfFile)
-	o.TCP = helpers.MergeWithBool(o.TCP, other.TCP)
-	o.CustomPort = helpers.MergeWithUint16(o.CustomPort, other.CustomPort)
-	o.PIAEncPreset = helpers.MergeWithStringPtr(o.PIAEncPreset, other.PIAEncPreset)
+	o.ConfFile = gosettings.MergeWithPointer(o.ConfFile, other.ConfFile)
+	o.TCP = gosettings.MergeWithPointer(o.TCP, other.TCP)
+	o.CustomPort = gosettings.MergeWithPointer(o.CustomPort, other.CustomPort)
+	o.PIAEncPreset = gosettings.MergeWithPointer(o.PIAEncPreset, other.PIAEncPreset)
 }
 
 func (o *OpenVPNSelection) overrideWith(other OpenVPNSelection) {
-	o.ConfFile = helpers.OverrideWithStringPtr(o.ConfFile, other.ConfFile)
-	o.TCP = helpers.OverrideWithBool(o.TCP, other.TCP)
-	o.CustomPort = helpers.OverrideWithUint16(o.CustomPort, other.CustomPort)
-	o.PIAEncPreset = helpers.OverrideWithStringPtr(o.PIAEncPreset, other.PIAEncPreset)
+	o.ConfFile = gosettings.OverrideWithPointer(o.ConfFile, other.ConfFile)
+	o.TCP = gosettings.OverrideWithPointer(o.TCP, other.TCP)
+	o.CustomPort = gosettings.OverrideWithPointer(o.CustomPort, other.CustomPort)
+	o.PIAEncPreset = gosettings.OverrideWithPointer(o.PIAEncPreset, other.PIAEncPreset)
 }
 
 func (o *OpenVPNSelection) setDefaults(vpnProvider string) {
-	o.ConfFile = helpers.DefaultStringPtr(o.ConfFile, "")
-	o.TCP = helpers.DefaultBool(o.TCP, false)
-	o.CustomPort = helpers.DefaultUint16(o.CustomPort, 0)
+	o.ConfFile = gosettings.DefaultPointer(o.ConfFile, "")
+	o.TCP = gosettings.DefaultPointer(o.TCP, false)
+	o.CustomPort = gosettings.DefaultPointer(o.CustomPort, 0)
 
 	var defaultEncPreset string
 	if vpnProvider == providers.PrivateInternetAccess {
 		defaultEncPreset = presets.Strong
 	}
-	o.PIAEncPreset = helpers.DefaultStringPtr(o.PIAEncPreset, defaultEncPreset)
+	o.PIAEncPreset = gosettings.DefaultPointer(o.PIAEncPreset, defaultEncPreset)
 }
 
 func (o OpenVPNSelection) String() string {

internal/configuration/settings/portforward.go

@@ -3,10 +3,10 @@ package settings
 import (
 	"fmt"
 	"path/filepath"
-	"strings"
 
-	"github.com/qdm12/gluetun/internal/configuration/settings/helpers"
 	"github.com/qdm12/gluetun/internal/constants/providers"
+	"github.com/qdm12/gosettings"
+	"github.com/qdm12/gosettings/validate"
 	"github.com/qdm12/gotree"
 )
 
@@ -14,24 +14,42 @@ import (
 type PortForwarding struct {
 	// Enabled is true if port forwarding should be activated.
 	// It cannot be nil for the internal state.
-	Enabled *bool
+	Enabled *bool `json:"enabled"`
+	// Provider is set to specify which custom port forwarding code
+	// should be used. This is especially necessary for the custom
+	// provider using Wireguard for a provider where Wireguard is not
+	// natively supported but custom port forwading code is available.
+	// It defaults to the empty string, meaning the current provider
+	// should be the one used for port forwarding.
+	// It cannot be nil for the internal state.
+	Provider *string `json:"provider"`
 	// Filepath is the port forwarding status file path
 	// to use. It can be the empty string to indicate not
 	// to write to a file. It cannot be nil for the
 	// internal state
-	Filepath *string
+	Filepath *string `json:"status_file_path"`
+	// ListeningPort is the port traffic would be redirected to from the
+	// forwarded port. The redirection is disabled if it is set to 0, which
+	// is its default as well.
+	ListeningPort *uint16 `json:"listening_port"`
 }
 
-func (p PortForwarding) validate(vpnProvider string) (err error) {
+func (p PortForwarding) Validate(vpnProvider string) (err error) {
 	if !*p.Enabled {
 		return nil
 	}
 
-	// Validate Enabled
-	validProviders := []string{providers.PrivateInternetAccess}
-	if !helpers.IsOneOf(vpnProvider, validProviders...) {
-		return fmt.Errorf("%w: for provider %s, it is only available for %s",
-			ErrPortForwardingEnabled, vpnProvider, strings.Join(validProviders, ", "))
+	// Validate current provider or custom provider specified
+	providerSelected := vpnProvider
+	if *p.Provider != "" {
+		providerSelected = *p.Provider
+	}
+	validProviders := []string{
+		providers.PrivateInternetAccess,
+		providers.Protonvpn,
+	}
+	if err = validate.IsOneOf(providerSelected, validProviders...); err != nil {
+		return fmt.Errorf("%w: %w", ErrPortForwardingEnabled, err)
 	}
 
 	// Validate Filepath
@@ -45,26 +63,34 @@ func (p PortForwarding) validate(vpnProvider string) (err error) {
 	return nil
 }
 
-func (p *PortForwarding) copy() (copied PortForwarding) {
+func (p *PortForwarding) Copy() (copied PortForwarding) {
 	return PortForwarding{
-		Enabled:  helpers.CopyBoolPtr(p.Enabled),
-		Filepath: helpers.CopyStringPtr(p.Filepath),
+		Enabled:       gosettings.CopyPointer(p.Enabled),
+		Provider:      gosettings.CopyPointer(p.Provider),
+		Filepath:      gosettings.CopyPointer(p.Filepath),
+		ListeningPort: gosettings.CopyPointer(p.ListeningPort),
 	}
 }
 
 func (p *PortForwarding) mergeWith(other PortForwarding) {
-	p.Enabled = helpers.MergeWithBool(p.Enabled, other.Enabled)
-	p.Filepath = helpers.MergeWithStringPtr(p.Filepath, other.Filepath)
+	p.Enabled = gosettings.MergeWithPointer(p.Enabled, other.Enabled)
+	p.Provider = gosettings.MergeWithPointer(p.Provider, other.Provider)
+	p.Filepath = gosettings.MergeWithPointer(p.Filepath, other.Filepath)
+	p.ListeningPort = gosettings.MergeWithPointer(p.ListeningPort, other.ListeningPort)
 }
 
-func (p *PortForwarding) overrideWith(other PortForwarding) {
-	p.Enabled = helpers.OverrideWithBool(p.Enabled, other.Enabled)
-	p.Filepath = helpers.OverrideWithStringPtr(p.Filepath, other.Filepath)
+func (p *PortForwarding) OverrideWith(other PortForwarding) {
+	p.Enabled = gosettings.OverrideWithPointer(p.Enabled, other.Enabled)
+	p.Provider = gosettings.OverrideWithPointer(p.Provider, other.Provider)
+	p.Filepath = gosettings.OverrideWithPointer(p.Filepath, other.Filepath)
+	p.ListeningPort = gosettings.OverrideWithPointer(p.ListeningPort, other.ListeningPort)
 }
 
 func (p *PortForwarding) setDefaults() {
-	p.Enabled = helpers.DefaultBool(p.Enabled, false)
-	p.Filepath = helpers.DefaultStringPtr(p.Filepath, "/tmp/gluetun/forwarded_port")
+	p.Enabled = gosettings.DefaultPointer(p.Enabled, false)
+	p.Provider = gosettings.DefaultPointer(p.Provider, "")
+	p.Filepath = gosettings.DefaultPointer(p.Filepath, "/tmp/gluetun/forwarded_port")
+	p.ListeningPort = gosettings.DefaultPointer(p.ListeningPort, 0)
 }
 
 func (p PortForwarding) String() string {
@@ -77,7 +103,18 @@ func (p PortForwarding) toLinesNode() (node *gotree.Node) {
 	}
 
 	node = gotree.New("Automatic port forwarding settings:")
-	node.Appendf("Enabled: yes")
+
+	listeningPort := "disabled"
+	if *p.ListeningPort != 0 {
+		listeningPort = fmt.Sprintf("%d", *p.ListeningPort)
+	}
+	node.Appendf("Redirection listening port: %s", listeningPort)
+
+	if *p.Provider == "" {
+		node.Appendf("Use port forwarding code for current provider")
+	} else {
+		node.Appendf("Use code for provider: %s", *p.Provider)
+	}
 
 	filepath := *p.Filepath
 	if filepath == "" {

internal/configuration/settings/provider.go

@@ -3,9 +3,10 @@ package settings
 import (
 	"fmt"
 
-	"github.com/qdm12/gluetun/internal/configuration/settings/helpers"
 	"github.com/qdm12/gluetun/internal/constants/providers"
 	"github.com/qdm12/gluetun/internal/constants/vpn"
+	"github.com/qdm12/gosettings"
+	"github.com/qdm12/gosettings/validate"
 	"github.com/qdm12/gotree"
 )
 
@@ -13,12 +14,12 @@ import (
 type Provider struct {
 	// Name is the VPN service provider name.
 	// It cannot be nil in the internal state.
-	Name *string
+	Name *string `json:"name"`
 	// ServerSelection is the settings to
 	// select the VPN server.
-	ServerSelection ServerSelection
+	ServerSelection ServerSelection `json:"server_selection"`
 	// PortForwarding is the settings about port forwarding.
-	PortForwarding PortForwarding
+	PortForwarding PortForwarding `json:"port_forwarding"`
 }
 
 // TODO v4 remove pointer for receiver (because of Surfshark).
@@ -30,15 +31,17 @@ 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.Nordvpn,
+			providers.Surfshark,
 			providers.Windscribe,
 		}
 	}
-	if !helpers.IsOneOf(*p.Name, validNames...) {
-		return fmt.Errorf("%w: %q can only be one of %s",
-			ErrVPNProviderNameNotValid, *p.Name, helpers.ChoicesOrString(validNames))
+	if err = validate.IsOneOf(*p.Name, validNames...); err != nil {
+		return fmt.Errorf("%w for Wireguard: %w", ErrVPNProviderNameNotValid, err)
 	}
 
 	err = p.ServerSelection.validate(*p.Name, storage)
@@ -46,7 +49,7 @@ func (p *Provider) validate(vpnType string, storage Storage) (err error) {
 		return fmt.Errorf("server selection: %w", err)
 	}
 
-	err = p.PortForwarding.validate(*p.Name)
+	err = p.PortForwarding.Validate(*p.Name)
 	if err != nil {
 		return fmt.Errorf("port forwarding: %w", err)
 	}
@@ -56,26 +59,26 @@ func (p *Provider) validate(vpnType string, storage Storage) (err error) {
 
 func (p *Provider) copy() (copied Provider) {
 	return Provider{
-		Name:            helpers.CopyStringPtr(p.Name),
+		Name:            gosettings.CopyPointer(p.Name),
 		ServerSelection: p.ServerSelection.copy(),
-		PortForwarding:  p.PortForwarding.copy(),
+		PortForwarding:  p.PortForwarding.Copy(),
 	}
 }
 
 func (p *Provider) mergeWith(other Provider) {
-	p.Name = helpers.MergeWithStringPtr(p.Name, other.Name)
+	p.Name = gosettings.MergeWithPointer(p.Name, other.Name)
 	p.ServerSelection.mergeWith(other.ServerSelection)
 	p.PortForwarding.mergeWith(other.PortForwarding)
 }
 
 func (p *Provider) overrideWith(other Provider) {
-	p.Name = helpers.OverrideWithStringPtr(p.Name, other.Name)
+	p.Name = gosettings.OverrideWithPointer(p.Name, other.Name)
 	p.ServerSelection.overrideWith(other.ServerSelection)
-	p.PortForwarding.overrideWith(other.PortForwarding)
+	p.PortForwarding.OverrideWith(other.PortForwarding)
 }
 
 func (p *Provider) setDefaults() {
-	p.Name = helpers.DefaultStringPtr(p.Name, providers.PrivateInternetAccess)
+	p.Name = gosettings.DefaultPointer(p.Name, providers.PrivateInternetAccess)
 	p.ServerSelection.setDefaults(*p.Name)
 	p.PortForwarding.setDefaults()
 }

internal/configuration/settings/publicip.go

@@ -5,7 +5,8 @@ import (
 	"path/filepath"
 	"time"
 
-	"github.com/qdm12/gluetun/internal/configuration/settings/helpers"
+	"github.com/qdm12/gluetun/internal/publicip/api"
+	"github.com/qdm12/gosettings"
 	"github.com/qdm12/gotree"
 )
 
@@ -21,6 +22,28 @@ type PublicIP struct {
 	// to write to a file. It cannot be nil for the
 	// internal state
 	IPFilepath *string
+	// API is the API name to use to fetch public IP information.
+	// It can be ipinfo or ip2location. It defaults to ipinfo.
+	API string
+	// APIToken is the token to use for the IP data service
+	// such as ipinfo.io. It can be the empty string to
+	// indicate not to use a token. It cannot be nil for the
+	// internal state.
+	APIToken *string
+}
+
+// UpdateWith deep copies the receiving settings, overrides the copy with
+// fields set in the partialUpdate argument, validates the new settings
+// and returns them if they are valid, or returns an error otherwise.
+// In all cases, the receiving settings are unmodified.
+func (p PublicIP) UpdateWith(partialUpdate PublicIP) (updatedSettings PublicIP, err error) {
+	updatedSettings = p.copy()
+	updatedSettings.overrideWith(partialUpdate)
+	err = updatedSettings.validate()
+	if err != nil {
+		return updatedSettings, fmt.Errorf("validating updated settings: %w", err)
+	}
+	return updatedSettings, nil
 }
 
 func (p PublicIP) validate() (err error) {
@@ -37,30 +60,43 @@ func (p PublicIP) validate() (err error) {
 		}
 	}
 
+	_, err = api.ParseProvider(p.API)
+	if err != nil {
+		return fmt.Errorf("API name: %w", err)
+	}
+
 	return nil
 }
 
 func (p *PublicIP) copy() (copied PublicIP) {
 	return PublicIP{
-		Period:     helpers.CopyDurationPtr(p.Period),
-		IPFilepath: helpers.CopyStringPtr(p.IPFilepath),
+		Period:     gosettings.CopyPointer(p.Period),
+		IPFilepath: gosettings.CopyPointer(p.IPFilepath),
+		API:        p.API,
+		APIToken:   gosettings.CopyPointer(p.APIToken),
 	}
 }
 
 func (p *PublicIP) mergeWith(other PublicIP) {
-	p.Period = helpers.MergeWithDuration(p.Period, other.Period)
-	p.IPFilepath = helpers.MergeWithStringPtr(p.IPFilepath, other.IPFilepath)
+	p.Period = gosettings.MergeWithPointer(p.Period, other.Period)
+	p.IPFilepath = gosettings.MergeWithPointer(p.IPFilepath, other.IPFilepath)
+	p.API = gosettings.MergeWithString(p.API, other.API)
+	p.APIToken = gosettings.MergeWithPointer(p.APIToken, other.APIToken)
 }
 
 func (p *PublicIP) overrideWith(other PublicIP) {
-	p.Period = helpers.OverrideWithDuration(p.Period, other.Period)
-	p.IPFilepath = helpers.OverrideWithStringPtr(p.IPFilepath, other.IPFilepath)
+	p.Period = gosettings.OverrideWithPointer(p.Period, other.Period)
+	p.IPFilepath = gosettings.OverrideWithPointer(p.IPFilepath, other.IPFilepath)
+	p.API = gosettings.OverrideWithString(p.API, other.API)
+	p.APIToken = gosettings.OverrideWithPointer(p.APIToken, other.APIToken)
 }
 
 func (p *PublicIP) setDefaults() {
 	const defaultPeriod = 12 * time.Hour
-	p.Period = helpers.DefaultDuration(p.Period, defaultPeriod)
-	p.IPFilepath = helpers.DefaultStringPtr(p.IPFilepath, "/tmp/gluetun/ip")
+	p.Period = gosettings.DefaultPointer(p.Period, defaultPeriod)
+	p.IPFilepath = gosettings.DefaultPointer(p.IPFilepath, "/tmp/gluetun/ip")
+	p.API = gosettings.DefaultString(p.API, "ipinfo")
+	p.APIToken = gosettings.DefaultPointer(p.APIToken, "")
 }
 
 func (p PublicIP) String() string {
@@ -85,5 +121,11 @@ func (p PublicIP) toLinesNode() (node *gotree.Node) {
 		node.Appendf("IP file path: %s", *p.IPFilepath)
 	}
 
+	node.Appendf("Public IP data API: %s", p.API)
+
+	if *p.APIToken != "" {
+		node.Appendf("API token: %s", gosettings.ObfuscateKey(*p.APIToken))
+	}
+
 	return node
 }

internal/configuration/settings/server.go

@@ -6,7 +6,7 @@ import (
 	"os"
 	"strconv"
 
-	"github.com/qdm12/gluetun/internal/configuration/settings/helpers"
+	"github.com/qdm12/gosettings"
 	"github.com/qdm12/gotree"
 )
 
@@ -43,29 +43,29 @@ func (c ControlServer) validate() (err error) {
 
 func (c *ControlServer) copy() (copied ControlServer) {
 	return ControlServer{
-		Address: helpers.CopyStringPtr(c.Address),
-		Log:     helpers.CopyBoolPtr(c.Log),
+		Address: gosettings.CopyPointer(c.Address),
+		Log:     gosettings.CopyPointer(c.Log),
 	}
 }
 
 // mergeWith merges the other settings into any
 // unset field of the receiver settings object.
 func (c *ControlServer) mergeWith(other ControlServer) {
-	c.Address = helpers.MergeWithStringPtr(c.Address, other.Address)
-	c.Log = helpers.MergeWithBool(c.Log, other.Log)
+	c.Address = gosettings.MergeWithPointer(c.Address, other.Address)
+	c.Log = gosettings.MergeWithPointer(c.Log, other.Log)
 }
 
 // overrideWith overrides fields of the receiver
 // settings object with any field set in the other
 // settings.
 func (c *ControlServer) overrideWith(other ControlServer) {
-	c.Address = helpers.OverrideWithStringPtr(c.Address, other.Address)
-	c.Log = helpers.OverrideWithBool(c.Log, other.Log)
+	c.Address = gosettings.OverrideWithPointer(c.Address, other.Address)
+	c.Log = gosettings.OverrideWithPointer(c.Log, other.Log)
 }
 
 func (c *ControlServer) setDefaults() {
-	c.Address = helpers.DefaultStringPtr(c.Address, ":8000")
-	c.Log = helpers.DefaultBool(c.Log, true)
+	c.Address = gosettings.DefaultPointer(c.Address, ":8000")
+	c.Log = gosettings.DefaultPointer(c.Log, true)
 }
 
 func (c ControlServer) String() string {
@@ -75,6 +75,6 @@ func (c ControlServer) String() string {
 func (c ControlServer) toLinesNode() (node *gotree.Node) {
 	node = gotree.New("Control server settings:")
 	node.Appendf("Listening address: %s", *c.Address)
-	node.Appendf("Logging: %s", helpers.BoolPtrToYesNo(c.Log))
+	node.Appendf("Logging: %s", gosettings.BoolToYesNo(c.Log))
 	return node
 }

internal/configuration/settings/serverselection.go

@@ -3,7 +3,7 @@ package settings
 import (
 	"errors"
 	"fmt"
-	"net"
+	"net/netip"
 	"strings"
 
 	"github.com/qdm12/gluetun/internal/configuration/settings/helpers"
@@ -11,6 +11,8 @@ import (
 	"github.com/qdm12/gluetun/internal/constants/providers"
 	"github.com/qdm12/gluetun/internal/constants/vpn"
 	"github.com/qdm12/gluetun/internal/models"
+	"github.com/qdm12/gosettings"
+	"github.com/qdm12/gosettings/validate"
 	"github.com/qdm12/gotree"
 )
 
@@ -18,53 +20,64 @@ type ServerSelection struct { //nolint:maligned
 	// VPN is the VPN type which can be 'openvpn'
 	// or 'wireguard'. It cannot be the empty string
 	// in the internal state.
-	VPN string
+	VPN string `json:"vpn"`
 	// TargetIP is the server endpoint IP address to use.
 	// It will override any IP address from the picked
-	// built-in server. It cannot be nil in the internal
-	// state, and can be set to an empty net.IP{} to indicate
+	// built-in server. It cannot be the empty value in the internal
+	// state, and can be set to the unspecified address to indicate
 	// there is not target IP address to use.
-	TargetIP net.IP
-	// Counties is the list of countries to filter VPN servers with.
-	Countries []string
+	TargetIP netip.Addr `json:"target_ip"`
+	// Countries is the list of countries to filter VPN servers with.
+	Countries []string `json:"countries"`
+	// Categories is the list of categories to filter VPN servers with.
+	Categories []string `json:"categories"`
 	// Regions is the list of regions to filter VPN servers with.
-	Regions []string
+	Regions []string `json:"regions"`
 	// Cities is the list of cities to filter VPN servers with.
-	Cities []string
+	Cities []string `json:"cities"`
 	// ISPs is the list of ISP names to filter VPN servers with.
-	ISPs []string
+	ISPs []string `json:"isps"`
 	// Names is the list of server names to filter VPN servers with.
-	Names []string
+	Names []string `json:"names"`
 	// Numbers is the list of server numbers to filter VPN servers with.
-	Numbers []uint16
+	Numbers []uint16 `json:"numbers"`
 	// Hostnames is the list of hostnames to filter VPN servers with.
-	Hostnames []string
+	Hostnames []string `json:"hostnames"`
 	// OwnedOnly is true if VPN provider servers that are not owned
 	// should be filtered. This is used with Mullvad.
-	OwnedOnly *bool
+	OwnedOnly *bool `json:"owned_only"`
 	// FreeOnly is true if VPN servers that are not free should
 	// be filtered. This is used with ProtonVPN and VPN Unlimited.
-	FreeOnly *bool
+	FreeOnly *bool `json:"free_only"`
+	// PremiumOnly is true if VPN servers that are not premium should
+	// be filtered. This is used with VPN Secure.
+	// TODO extend to providers using FreeOnly.
+	PremiumOnly *bool `json:"premium_only"`
 	// StreamOnly is true if VPN servers not for streaming should
 	// be filtered. This is used with VPNUnlimited.
-	StreamOnly *bool
+	StreamOnly *bool `json:"stream_only"`
 	// MultiHopOnly is true if VPN servers that are not multihop
 	// should be filtered. This is used with Surfshark.
-	MultiHopOnly *bool
-
+	MultiHopOnly *bool `json:"multi_hop_only"`
+	// PortForwardOnly is true if VPN servers that don't support
+	// port forwarding should be filtered. This is used with PIA.
+	PortForwardOnly *bool `json:"port_forward_only"`
 	// OpenVPN contains settings to select OpenVPN servers
 	// and the final connection.
-	OpenVPN OpenVPNSelection
+	OpenVPN OpenVPNSelection `json:"openvpn"`
 	// Wireguard contains settings to select Wireguard servers
 	// and the final connection.
-	Wireguard WireguardSelection
+	Wireguard WireguardSelection `json:"wireguard"`
 }
 
 var (
-	ErrOwnedOnlyNotSupported    = errors.New("owned only filter is not supported")
-	ErrFreeOnlyNotSupported     = errors.New("free only filter is not supported")
-	ErrStreamOnlyNotSupported   = errors.New("stream only filter is not supported")
-	ErrMultiHopOnlyNotSupported = errors.New("multi hop only filter is not supported")
+	ErrOwnedOnlyNotSupported       = errors.New("owned only filter is not supported")
+	ErrFreeOnlyNotSupported        = errors.New("free only filter is not supported")
+	ErrPremiumOnlyNotSupported     = errors.New("premium only filter is not supported")
+	ErrStreamOnlyNotSupported      = errors.New("stream only filter is not supported")
+	ErrMultiHopOnlyNotSupported    = errors.New("multi hop only filter is not supported")
+	ErrPortForwardOnlyNotSupported = errors.New("port forwarding only filter is not supported")
+	ErrFreePremiumBothSet          = errors.New("free only and premium only filters are both set")
 )
 
 func (ss *ServerSelection) validate(vpnServiceProvider string,
@@ -80,12 +93,17 @@ func (ss *ServerSelection) validate(vpnServiceProvider string,
 		return err // already wrapped error
 	}
 
+	// Retro-compatibility
+	switch vpnServiceProvider {
+	case providers.Nordvpn:
+		*ss = nordvpnRetroRegion(*ss, filterChoices.Regions, filterChoices.Countries)
+	case providers.Surfshark:
+		*ss = surfsharkRetroRegion(*ss)
+	}
+
 	err = validateServerFilters(*ss, filterChoices)
 	if err != nil {
-		if errors.Is(err, helpers.ErrNoChoice) {
-			return fmt.Errorf("for VPN service provider %s: %w", vpnServiceProvider, err)
-		}
-		return err // already wrapped error
+		return fmt.Errorf("for VPN service provider %s: %w", vpnServiceProvider, err)
 	}
 
 	if *ss.OwnedOnly &&
@@ -103,6 +121,18 @@ func (ss *ServerSelection) validate(vpnServiceProvider string,
 			ErrFreeOnlyNotSupported, vpnServiceProvider)
 	}
 
+	if *ss.PremiumOnly &&
+		!helpers.IsOneOf(vpnServiceProvider,
+			providers.VPNSecure,
+		) {
+		return fmt.Errorf("%w: for VPN service provider %s",
+			ErrPremiumOnlyNotSupported, vpnServiceProvider)
+	}
+
+	if *ss.FreeOnly && *ss.PremiumOnly {
+		return fmt.Errorf("%w", ErrFreePremiumBothSet)
+	}
+
 	if *ss.StreamOnly &&
 		!helpers.IsOneOf(vpnServiceProvider,
 			providers.Protonvpn,
@@ -118,6 +148,15 @@ func (ss *ServerSelection) validate(vpnServiceProvider string,
 			ErrMultiHopOnlyNotSupported, vpnServiceProvider)
 	}
 
+	if *ss.PortForwardOnly &&
+		vpnServiceProvider != providers.PrivateInternetAccess {
+		// ProtonVPN also supports port forwarding, but on all their servers, so these
+		// don't have the port forwarding boolean field. As a consequence, we only allow
+		// the use of PortForwardOnly for Private Internet Access.
+		return fmt.Errorf("%w: for VPN service provider %s",
+			ErrPortForwardOnlyNotSupported, vpnServiceProvider)
+	}
+
 	if ss.VPN == vpn.OpenVPN {
 		err = ss.OpenVPN.validate(vpnServiceProvider)
 		if err != nil {
@@ -141,11 +180,14 @@ func getLocationFilterChoices(vpnServiceProvider string,
 	if vpnServiceProvider == providers.Surfshark {
 		// // Retro compatibility
 		// TODO v4 remove
-		filterChoices.Regions = append(filterChoices.Regions, validation.SurfsharkRetroLocChoices()...)
-		if err := helpers.AreAllOneOf(ss.Regions, filterChoices.Regions); err != nil {
-			return models.FilterChoices{}, fmt.Errorf("%w: %s", ErrRegionNotValid, err)
+		newAndRetroRegions := append(filterChoices.Regions, validation.SurfsharkRetroLocChoices()...) //nolint:gocritic
+		err := validate.AreAllOneOfCaseInsensitive(ss.Regions, newAndRetroRegions)
+		if err != nil {
+			// Only return error comparing with newer regions, we don't want to confuse the user
+			// with the retro regions in the error message.
+			err = validate.AreAllOneOfCaseInsensitive(ss.Regions, filterChoices.Regions)
+			return models.FilterChoices{}, fmt.Errorf("%w: %w", ErrRegionNotValid, err)
 		}
-		*ss = surfsharkRetroRegion(*ss)
 	}
 
 	return filterChoices, nil
@@ -154,28 +196,39 @@ func getLocationFilterChoices(vpnServiceProvider string,
 // validateServerFilters validates filters against the choices given as arguments.
 // Set an argument to nil to pass the check for a particular filter.
 func validateServerFilters(settings ServerSelection, filterChoices models.FilterChoices) (err error) {
-	if err := helpers.AreAllOneOf(settings.Countries, filterChoices.Countries); err != nil {
-		return fmt.Errorf("%w: %s", ErrCountryNotValid, err)
+	err = validate.AreAllOneOfCaseInsensitive(settings.Countries, filterChoices.Countries)
+	if err != nil {
+		return fmt.Errorf("%w: %w", ErrCountryNotValid, err)
 	}
 
-	if err := helpers.AreAllOneOf(settings.Regions, filterChoices.Regions); err != nil {
-		return fmt.Errorf("%w: %s", ErrRegionNotValid, err)
+	err = validate.AreAllOneOfCaseInsensitive(settings.Regions, filterChoices.Regions)
+	if err != nil {
+		return fmt.Errorf("%w: %w", ErrRegionNotValid, err)
 	}
 
-	if err := helpers.AreAllOneOf(settings.Cities, filterChoices.Cities); err != nil {
-		return fmt.Errorf("%w: %s", ErrCityNotValid, err)
+	err = validate.AreAllOneOfCaseInsensitive(settings.Cities, filterChoices.Cities)
+	if err != nil {
+		return fmt.Errorf("%w: %w", ErrCityNotValid, err)
 	}
 
-	if err := helpers.AreAllOneOf(settings.ISPs, filterChoices.ISPs); err != nil {
-		return fmt.Errorf("%w: %s", ErrISPNotValid, err)
+	err = validate.AreAllOneOfCaseInsensitive(settings.ISPs, filterChoices.ISPs)
+	if err != nil {
+		return fmt.Errorf("%w: %w", ErrISPNotValid, err)
 	}
 
-	if err := helpers.AreAllOneOf(settings.Hostnames, filterChoices.Hostnames); err != nil {
-		return fmt.Errorf("%w: %s", ErrHostnameNotValid, err)
+	err = validate.AreAllOneOfCaseInsensitive(settings.Hostnames, filterChoices.Hostnames)
+	if err != nil {
+		return fmt.Errorf("%w: %w", ErrHostnameNotValid, err)
 	}
 
-	if err := helpers.AreAllOneOf(settings.Names, filterChoices.Names); err != nil {
-		return fmt.Errorf("%w: %s", ErrNameNotValid, err)
+	err = validate.AreAllOneOfCaseInsensitive(settings.Names, filterChoices.Names)
+	if err != nil {
+		return fmt.Errorf("%w: %w", ErrNameNotValid, err)
+	}
+
+	err = validate.AreAllOneOfCaseInsensitive(settings.Categories, filterChoices.Categories)
+	if err != nil {
+		return fmt.Errorf("%w: %w", ErrCategoryNotValid, err)
 	}
 
 	return nil
@@ -183,68 +236,79 @@ func validateServerFilters(settings ServerSelection, filterChoices models.Filter
 
 func (ss *ServerSelection) copy() (copied ServerSelection) {
 	return ServerSelection{
-		VPN:          ss.VPN,
-		TargetIP:     helpers.CopyIP(ss.TargetIP),
-		Countries:    helpers.CopyStringSlice(ss.Countries),
-		Regions:      helpers.CopyStringSlice(ss.Regions),
-		Cities:       helpers.CopyStringSlice(ss.Cities),
-		ISPs:         helpers.CopyStringSlice(ss.ISPs),
-		Hostnames:    helpers.CopyStringSlice(ss.Hostnames),
-		Names:        helpers.CopyStringSlice(ss.Names),
-		Numbers:      helpers.CopyUint16Slice(ss.Numbers),
-		OwnedOnly:    helpers.CopyBoolPtr(ss.OwnedOnly),
-		FreeOnly:     helpers.CopyBoolPtr(ss.FreeOnly),
-		StreamOnly:   helpers.CopyBoolPtr(ss.StreamOnly),
-		MultiHopOnly: helpers.CopyBoolPtr(ss.MultiHopOnly),
-		OpenVPN:      ss.OpenVPN.copy(),
-		Wireguard:    ss.Wireguard.copy(),
+		VPN:             ss.VPN,
+		TargetIP:        ss.TargetIP,
+		Countries:       gosettings.CopySlice(ss.Countries),
+		Categories:      gosettings.CopySlice(ss.Categories),
+		Regions:         gosettings.CopySlice(ss.Regions),
+		Cities:          gosettings.CopySlice(ss.Cities),
+		ISPs:            gosettings.CopySlice(ss.ISPs),
+		Hostnames:       gosettings.CopySlice(ss.Hostnames),
+		Names:           gosettings.CopySlice(ss.Names),
+		Numbers:         gosettings.CopySlice(ss.Numbers),
+		OwnedOnly:       gosettings.CopyPointer(ss.OwnedOnly),
+		FreeOnly:        gosettings.CopyPointer(ss.FreeOnly),
+		PremiumOnly:     gosettings.CopyPointer(ss.PremiumOnly),
+		StreamOnly:      gosettings.CopyPointer(ss.StreamOnly),
+		PortForwardOnly: gosettings.CopyPointer(ss.PortForwardOnly),
+		MultiHopOnly:    gosettings.CopyPointer(ss.MultiHopOnly),
+		OpenVPN:         ss.OpenVPN.copy(),
+		Wireguard:       ss.Wireguard.copy(),
 	}
 }
 
 func (ss *ServerSelection) mergeWith(other ServerSelection) {
-	ss.VPN = helpers.MergeWithString(ss.VPN, other.VPN)
-	ss.TargetIP = helpers.MergeWithIP(ss.TargetIP, other.TargetIP)
-	ss.Countries = helpers.MergeStringSlices(ss.Countries, other.Countries)
-	ss.Regions = helpers.MergeStringSlices(ss.Regions, other.Regions)
-	ss.Cities = helpers.MergeStringSlices(ss.Cities, other.Cities)
-	ss.ISPs = helpers.MergeStringSlices(ss.ISPs, other.ISPs)
-	ss.Hostnames = helpers.MergeStringSlices(ss.Hostnames, other.Hostnames)
-	ss.Names = helpers.MergeStringSlices(ss.Names, other.Names)
-	ss.Numbers = helpers.MergeUint16Slices(ss.Numbers, other.Numbers)
-	ss.OwnedOnly = helpers.MergeWithBool(ss.OwnedOnly, other.OwnedOnly)
-	ss.FreeOnly = helpers.MergeWithBool(ss.FreeOnly, other.FreeOnly)
-	ss.StreamOnly = helpers.MergeWithBool(ss.StreamOnly, other.StreamOnly)
-	ss.MultiHopOnly = helpers.MergeWithBool(ss.MultiHopOnly, other.MultiHopOnly)
+	ss.VPN = gosettings.MergeWithString(ss.VPN, other.VPN)
+	ss.TargetIP = gosettings.MergeWithValidator(ss.TargetIP, other.TargetIP)
+	ss.Countries = gosettings.MergeWithSlice(ss.Countries, other.Countries)
+	ss.Categories = gosettings.MergeWithSlice(ss.Categories, other.Categories)
+	ss.Regions = gosettings.MergeWithSlice(ss.Regions, other.Regions)
+	ss.Cities = gosettings.MergeWithSlice(ss.Cities, other.Cities)
+	ss.ISPs = gosettings.MergeWithSlice(ss.ISPs, other.ISPs)
+	ss.Hostnames = gosettings.MergeWithSlice(ss.Hostnames, other.Hostnames)
+	ss.Names = gosettings.MergeWithSlice(ss.Names, other.Names)
+	ss.Numbers = gosettings.MergeWithSlice(ss.Numbers, other.Numbers)
+	ss.OwnedOnly = gosettings.MergeWithPointer(ss.OwnedOnly, other.OwnedOnly)
+	ss.FreeOnly = gosettings.MergeWithPointer(ss.FreeOnly, other.FreeOnly)
+	ss.PremiumOnly = gosettings.MergeWithPointer(ss.PremiumOnly, other.PremiumOnly)
+	ss.StreamOnly = gosettings.MergeWithPointer(ss.StreamOnly, other.StreamOnly)
+	ss.MultiHopOnly = gosettings.MergeWithPointer(ss.MultiHopOnly, other.MultiHopOnly)
+	ss.PortForwardOnly = gosettings.MergeWithPointer(ss.PortForwardOnly, other.PortForwardOnly)
 
 	ss.OpenVPN.mergeWith(other.OpenVPN)
 	ss.Wireguard.mergeWith(other.Wireguard)
 }
 
 func (ss *ServerSelection) overrideWith(other ServerSelection) {
-	ss.VPN = helpers.OverrideWithString(ss.VPN, other.VPN)
-	ss.TargetIP = helpers.OverrideWithIP(ss.TargetIP, other.TargetIP)
-	ss.Countries = helpers.OverrideWithStringSlice(ss.Countries, other.Countries)
-	ss.Regions = helpers.OverrideWithStringSlice(ss.Regions, other.Regions)
-	ss.Cities = helpers.OverrideWithStringSlice(ss.Cities, other.Cities)
-	ss.ISPs = helpers.OverrideWithStringSlice(ss.ISPs, other.ISPs)
-	ss.Hostnames = helpers.OverrideWithStringSlice(ss.Hostnames, other.Hostnames)
-	ss.Names = helpers.OverrideWithStringSlice(ss.Names, other.Names)
-	ss.Numbers = helpers.OverrideWithUint16Slice(ss.Numbers, other.Numbers)
-	ss.OwnedOnly = helpers.OverrideWithBool(ss.OwnedOnly, other.OwnedOnly)
-	ss.FreeOnly = helpers.OverrideWithBool(ss.FreeOnly, other.FreeOnly)
-	ss.StreamOnly = helpers.OverrideWithBool(ss.StreamOnly, other.StreamOnly)
-	ss.MultiHopOnly = helpers.OverrideWithBool(ss.MultiHopOnly, other.MultiHopOnly)
+	ss.VPN = gosettings.OverrideWithString(ss.VPN, other.VPN)
+	ss.TargetIP = gosettings.OverrideWithValidator(ss.TargetIP, other.TargetIP)
+	ss.Countries = gosettings.OverrideWithSlice(ss.Countries, other.Countries)
+	ss.Categories = gosettings.OverrideWithSlice(ss.Categories, other.Categories)
+	ss.Regions = gosettings.OverrideWithSlice(ss.Regions, other.Regions)
+	ss.Cities = gosettings.OverrideWithSlice(ss.Cities, other.Cities)
+	ss.ISPs = gosettings.OverrideWithSlice(ss.ISPs, other.ISPs)
+	ss.Hostnames = gosettings.OverrideWithSlice(ss.Hostnames, other.Hostnames)
+	ss.Names = gosettings.OverrideWithSlice(ss.Names, other.Names)
+	ss.Numbers = gosettings.OverrideWithSlice(ss.Numbers, other.Numbers)
+	ss.OwnedOnly = gosettings.OverrideWithPointer(ss.OwnedOnly, other.OwnedOnly)
+	ss.FreeOnly = gosettings.OverrideWithPointer(ss.FreeOnly, other.FreeOnly)
+	ss.PremiumOnly = gosettings.OverrideWithPointer(ss.PremiumOnly, other.PremiumOnly)
+	ss.StreamOnly = gosettings.OverrideWithPointer(ss.StreamOnly, other.StreamOnly)
+	ss.MultiHopOnly = gosettings.OverrideWithPointer(ss.MultiHopOnly, other.MultiHopOnly)
+	ss.PortForwardOnly = gosettings.OverrideWithPointer(ss.PortForwardOnly, other.PortForwardOnly)
 	ss.OpenVPN.overrideWith(other.OpenVPN)
 	ss.Wireguard.overrideWith(other.Wireguard)
 }
 
 func (ss *ServerSelection) setDefaults(vpnProvider string) {
-	ss.VPN = helpers.DefaultString(ss.VPN, vpn.OpenVPN)
-	ss.TargetIP = helpers.DefaultIP(ss.TargetIP, net.IP{})
-	ss.OwnedOnly = helpers.DefaultBool(ss.OwnedOnly, false)
-	ss.FreeOnly = helpers.DefaultBool(ss.FreeOnly, false)
-	ss.StreamOnly = helpers.DefaultBool(ss.StreamOnly, false)
-	ss.MultiHopOnly = helpers.DefaultBool(ss.MultiHopOnly, false)
+	ss.VPN = gosettings.DefaultString(ss.VPN, vpn.OpenVPN)
+	ss.TargetIP = gosettings.DefaultValidator(ss.TargetIP, netip.IPv4Unspecified())
+	ss.OwnedOnly = gosettings.DefaultPointer(ss.OwnedOnly, false)
+	ss.FreeOnly = gosettings.DefaultPointer(ss.FreeOnly, false)
+	ss.PremiumOnly = gosettings.DefaultPointer(ss.PremiumOnly, false)
+	ss.StreamOnly = gosettings.DefaultPointer(ss.StreamOnly, false)
+	ss.MultiHopOnly = gosettings.DefaultPointer(ss.MultiHopOnly, false)
+	ss.PortForwardOnly = gosettings.DefaultPointer(ss.PortForwardOnly, false)
 	ss.OpenVPN.setDefaults(vpnProvider)
 	ss.Wireguard.setDefaults()
 }
@@ -256,7 +320,7 @@ func (ss ServerSelection) String() string {
 func (ss ServerSelection) toLinesNode() (node *gotree.Node) {
 	node = gotree.New("Server selection settings:")
 	node.Appendf("VPN type: %s", ss.VPN)
-	if len(ss.TargetIP) > 0 {
+	if !ss.TargetIP.IsUnspecified() {
 		node.Appendf("Target IP address: %s", ss.TargetIP)
 	}
 
@@ -264,6 +328,10 @@ func (ss ServerSelection) toLinesNode() (node *gotree.Node) {
 		node.Appendf("Countries: %s", strings.Join(ss.Countries, ", "))
 	}
 
+	if len(ss.Categories) > 0 {
+		node.Appendf("Categories: %s", strings.Join(ss.Categories, ", "))
+	}
+
 	if len(ss.Regions) > 0 {
 		node.Appendf("Regions: %s", strings.Join(ss.Regions, ", "))
 	}
@@ -299,6 +367,10 @@ func (ss ServerSelection) toLinesNode() (node *gotree.Node) {
 		node.Appendf("Free only servers: yes")
 	}
 
+	if *ss.PremiumOnly {
+		node.Appendf("Premium only servers: yes")
+	}
+
 	if *ss.StreamOnly {
 		node.Appendf("Stream only servers: yes")
 	}

internal/configuration/settings/settings.go

@@ -3,6 +3,9 @@ package settings
 import (
 	"fmt"
 
+	"github.com/qdm12/gluetun/internal/configuration/settings/helpers"
+	"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 +34,7 @@ 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 +49,7 @@ 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)
 		},
 	}
 
@@ -73,7 +76,7 @@ func (s *Settings) copy() (copied Settings) {
 		System:        s.System.copy(),
 		Updater:       s.Updater.copy(),
 		Version:       s.Version.copy(),
-		VPN:           s.VPN.copy(),
+		VPN:           s.VPN.Copy(),
 		Pprof:         s.Pprof.Copy(),
 	}
 }
@@ -95,7 +98,7 @@ 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)
@@ -108,9 +111,9 @@ func (s *Settings) OverrideWith(other Settings,
 	patchedSettings.System.overrideWith(other.System)
 	patchedSettings.Updater.overrideWith(other.Updater)
 	patchedSettings.Version.overrideWith(other.Version)
-	patchedSettings.VPN.overrideWith(other.VPN)
+	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 +160,24 @@ 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 {
+		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.")
+	}
+
+	return warnings
+}

internal/configuration/settings/settings_test.go

@@ -34,13 +34,12 @@ 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
 ├── DNS settings:
-|   ├── DNS server address to use: 127.0.0.1
 |   ├── Keep existing nameserver(s): no
+|   ├── DNS server address to use: 127.0.0.1
 |   └── DNS over TLS settings:
 |       ├── Enabled: yes
 |       ├── Update period: every 24h0m0s
@@ -67,6 +66,9 @@ func Test_Settings_String(t *testing.T) {
 ├── Health settings:
 |   ├── Server listening address: 127.0.0.1:9999
 |   ├── Target address: cloudflare.com:443
+|   ├── Duration to wait after success: 5s
+|   ├── Read header timeout: 100ms
+|   ├── Read timeout: 500ms
 |   └── VPN wait durations:
 |       ├── Initial duration: 6s
 |       └── Additional duration: 5s
@@ -82,7 +84,8 @@ func Test_Settings_String(t *testing.T) {
 |   └── Process GID: 1000
 ├── Public IP settings:
 |   ├── Fetching: every 12h0m0s
-|   └── IP file path: /tmp/gluetun/ip
+|   ├── IP file path: /tmp/gluetun/ip
+|   └── Public IP data API: ipinfo
 └── Version settings:
     └── Enabled: yes`,
 		},

internal/configuration/settings/shadowsocks.go

@@ -1,7 +1,7 @@
 package settings
 
 import (
-	"github.com/qdm12/gluetun/internal/configuration/settings/helpers"
+	"github.com/qdm12/gosettings"
 	"github.com/qdm12/gotree"
 	"github.com/qdm12/ss-server/pkg/tcpudp"
 )
@@ -21,7 +21,7 @@ func (s Shadowsocks) validate() (err error) {
 
 func (s *Shadowsocks) copy() (copied Shadowsocks) {
 	return Shadowsocks{
-		Enabled:  helpers.CopyBoolPtr(s.Enabled),
+		Enabled:  gosettings.CopyPointer(s.Enabled),
 		Settings: s.Settings.Copy(),
 	}
 }
@@ -29,20 +29,20 @@ func (s *Shadowsocks) copy() (copied Shadowsocks) {
 // mergeWith merges the other settings into any
 // unset field of the receiver settings object.
 func (s *Shadowsocks) mergeWith(other Shadowsocks) {
-	s.Enabled = helpers.MergeWithBool(s.Enabled, other.Enabled)
-	s.Settings.MergeWith(other.Settings)
+	s.Enabled = gosettings.MergeWithPointer(s.Enabled, other.Enabled)
+	s.Settings = s.Settings.MergeWith(other.Settings)
 }
 
 // overrideWith overrides fields of the receiver
 // settings object with any field set in the other
 // settings.
 func (s *Shadowsocks) overrideWith(other Shadowsocks) {
-	s.Enabled = helpers.OverrideWithBool(s.Enabled, other.Enabled)
+	s.Enabled = gosettings.OverrideWithPointer(s.Enabled, other.Enabled)
 	s.Settings.OverrideWith(other.Settings)
 }
 
 func (s *Shadowsocks) setDefaults() {
-	s.Enabled = helpers.DefaultBool(s.Enabled, false)
+	s.Enabled = gosettings.DefaultPointer(s.Enabled, false)
 	s.Settings.SetDefaults()
 }
 
@@ -53,16 +53,16 @@ func (s Shadowsocks) String() string {
 func (s Shadowsocks) toLinesNode() (node *gotree.Node) {
 	node = gotree.New("Shadowsocks server settings:")
 
-	node.Appendf("Enabled: %s", helpers.BoolPtrToYesNo(s.Enabled))
+	node.Appendf("Enabled: %s", gosettings.BoolToYesNo(s.Enabled))
 	if !*s.Enabled {
 		return node
 	}
 
 	// TODO have ToLinesNode in qdm12/ss-server
-	node.Appendf("Listening address: %s", s.Address)
+	node.Appendf("Listening address: %s", *s.Address)
 	node.Appendf("Cipher: %s", s.CipherName)
-	node.Appendf("Password: %s", helpers.ObfuscatePassword(*s.Password))
-	node.Appendf("Log addresses: %s", helpers.BoolPtrToYesNo(s.LogAddresses))
+	node.Appendf("Password: %s", gosettings.ObfuscateKey(*s.Password))
+	node.Appendf("Log addresses: %s", gosettings.BoolToYesNo(s.LogAddresses))
 
 	return node
 }

internal/configuration/settings/system.go

@@ -1,7 +1,7 @@
 package settings
 
 import (
-	"github.com/qdm12/gluetun/internal/configuration/settings/helpers"
+	"github.com/qdm12/gosettings"
 	"github.com/qdm12/gotree"
 )
 
@@ -19,28 +19,28 @@ func (s System) validate() (err error) {
 
 func (s *System) copy() (copied System) {
 	return System{
-		PUID:     helpers.CopyUint32Ptr(s.PUID),
-		PGID:     helpers.CopyUint32Ptr(s.PGID),
+		PUID:     gosettings.CopyPointer(s.PUID),
+		PGID:     gosettings.CopyPointer(s.PGID),
 		Timezone: s.Timezone,
 	}
 }
 
 func (s *System) mergeWith(other System) {
-	s.PUID = helpers.MergeWithUint32(s.PUID, other.PUID)
-	s.PGID = helpers.MergeWithUint32(s.PGID, other.PGID)
-	s.Timezone = helpers.MergeWithString(s.Timezone, other.Timezone)
+	s.PUID = gosettings.MergeWithPointer(s.PUID, other.PUID)
+	s.PGID = gosettings.MergeWithPointer(s.PGID, other.PGID)
+	s.Timezone = gosettings.MergeWithString(s.Timezone, other.Timezone)
 }
 
 func (s *System) overrideWith(other System) {
-	s.PUID = helpers.OverrideWithUint32(s.PUID, other.PUID)
-	s.PGID = helpers.OverrideWithUint32(s.PGID, other.PGID)
-	s.Timezone = helpers.OverrideWithString(s.Timezone, other.Timezone)
+	s.PUID = gosettings.OverrideWithPointer(s.PUID, other.PUID)
+	s.PGID = gosettings.OverrideWithPointer(s.PGID, other.PGID)
+	s.Timezone = gosettings.OverrideWithString(s.Timezone, other.Timezone)
 }
 
 func (s *System) setDefaults() {
 	const defaultID = 1000
-	s.PUID = helpers.DefaultUint32(s.PUID, defaultID)
-	s.PGID = helpers.DefaultUint32(s.PGID, defaultID)
+	s.PUID = gosettings.DefaultPointer(s.PUID, defaultID)
+	s.PGID = gosettings.DefaultPointer(s.PGID, defaultID)
 }
 
 func (s System) String() string {

internal/configuration/settings/unbound.go

@@ -3,25 +3,24 @@ package settings
 import (
 	"errors"
 	"fmt"
-	"net"
+	"net/netip"
 
 	"github.com/qdm12/dns/pkg/provider"
 	"github.com/qdm12/dns/pkg/unbound"
-	"github.com/qdm12/gluetun/internal/configuration/settings/helpers"
+	"github.com/qdm12/gosettings"
 	"github.com/qdm12/gotree"
-	"inet.af/netaddr"
 )
 
 // Unbound is settings for the Unbound program.
 type Unbound struct {
-	Providers             []string
-	Caching               *bool
-	IPv6                  *bool
-	VerbosityLevel        *uint8
-	VerbosityDetailsLevel *uint8
-	ValidationLogLevel    *uint8
-	Username              string
-	Allowed               []netaddr.IPPrefix
+	Providers             []string       `json:"providers"`
+	Caching               *bool          `json:"caching"`
+	IPv6                  *bool          `json:"ipv6"`
+	VerbosityLevel        *uint8         `json:"verbosity_level"`
+	VerbosityDetailsLevel *uint8         `json:"verbosity_details_level"`
+	ValidationLogLevel    *uint8         `json:"validation_log_level"`
+	Username              string         `json:"username"`
+	Allowed               []netip.Prefix `json:"allowed"`
 }
 
 func (u *Unbound) setDefaults() {
@@ -31,26 +30,26 @@ func (u *Unbound) setDefaults() {
 		}
 	}
 
-	u.Caching = helpers.DefaultBool(u.Caching, true)
-	u.IPv6 = helpers.DefaultBool(u.IPv6, false)
+	u.Caching = gosettings.DefaultPointer(u.Caching, true)
+	u.IPv6 = gosettings.DefaultPointer(u.IPv6, false)
 
 	const defaultVerbosityLevel = 1
-	u.VerbosityLevel = helpers.DefaultUint8(u.VerbosityLevel, defaultVerbosityLevel)
+	u.VerbosityLevel = gosettings.DefaultPointer(u.VerbosityLevel, defaultVerbosityLevel)
 
 	const defaultVerbosityDetailsLevel = 0
-	u.VerbosityDetailsLevel = helpers.DefaultUint8(u.VerbosityDetailsLevel, defaultVerbosityDetailsLevel)
+	u.VerbosityDetailsLevel = gosettings.DefaultPointer(u.VerbosityDetailsLevel, defaultVerbosityDetailsLevel)
 
 	const defaultValidationLogLevel = 0
-	u.ValidationLogLevel = helpers.DefaultUint8(u.ValidationLogLevel, defaultValidationLogLevel)
+	u.ValidationLogLevel = gosettings.DefaultPointer(u.ValidationLogLevel, defaultValidationLogLevel)
 
 	if u.Allowed == nil {
-		u.Allowed = []netaddr.IPPrefix{
-			netaddr.IPPrefixFrom(netaddr.IPv4(0, 0, 0, 0), 0),
-			netaddr.IPPrefixFrom(netaddr.IPv6Raw([16]byte{}), 0),
+		u.Allowed = []netip.Prefix{
+			netip.PrefixFrom(netip.AddrFrom4([4]byte{}), 0),
+			netip.PrefixFrom(netip.AddrFrom16([16]byte{}), 0),
 		}
 	}
 
-	u.Username = helpers.DefaultString(u.Username, "root")
+	u.Username = gosettings.DefaultString(u.Username, "root")
 }
 
 var (
@@ -95,37 +94,37 @@ func (u Unbound) validate() (err error) {
 
 func (u Unbound) copy() (copied Unbound) {
 	return Unbound{
-		Providers:             helpers.CopyStringSlice(u.Providers),
-		Caching:               helpers.CopyBoolPtr(u.Caching),
-		IPv6:                  helpers.CopyBoolPtr(u.IPv6),
-		VerbosityLevel:        helpers.CopyUint8Ptr(u.VerbosityLevel),
-		VerbosityDetailsLevel: helpers.CopyUint8Ptr(u.VerbosityDetailsLevel),
-		ValidationLogLevel:    helpers.CopyUint8Ptr(u.ValidationLogLevel),
+		Providers:             gosettings.CopySlice(u.Providers),
+		Caching:               gosettings.CopyPointer(u.Caching),
+		IPv6:                  gosettings.CopyPointer(u.IPv6),
+		VerbosityLevel:        gosettings.CopyPointer(u.VerbosityLevel),
+		VerbosityDetailsLevel: gosettings.CopyPointer(u.VerbosityDetailsLevel),
+		ValidationLogLevel:    gosettings.CopyPointer(u.ValidationLogLevel),
 		Username:              u.Username,
-		Allowed:               helpers.CopyIPPrefixSlice(u.Allowed),
+		Allowed:               gosettings.CopySlice(u.Allowed),
 	}
 }
 
 func (u *Unbound) mergeWith(other Unbound) {
-	u.Providers = helpers.MergeStringSlices(u.Providers, other.Providers)
-	u.Caching = helpers.MergeWithBool(u.Caching, other.Caching)
-	u.IPv6 = helpers.MergeWithBool(u.IPv6, other.IPv6)
-	u.VerbosityLevel = helpers.MergeWithUint8(u.VerbosityLevel, other.VerbosityLevel)
-	u.VerbosityDetailsLevel = helpers.MergeWithUint8(u.VerbosityDetailsLevel, other.VerbosityDetailsLevel)
-	u.ValidationLogLevel = helpers.MergeWithUint8(u.ValidationLogLevel, other.ValidationLogLevel)
-	u.Username = helpers.MergeWithString(u.Username, other.Username)
-	u.Allowed = helpers.MergeIPPrefixesSlices(u.Allowed, other.Allowed)
+	u.Providers = gosettings.MergeWithSlice(u.Providers, other.Providers)
+	u.Caching = gosettings.MergeWithPointer(u.Caching, other.Caching)
+	u.IPv6 = gosettings.MergeWithPointer(u.IPv6, other.IPv6)
+	u.VerbosityLevel = gosettings.MergeWithPointer(u.VerbosityLevel, other.VerbosityLevel)
+	u.VerbosityDetailsLevel = gosettings.MergeWithPointer(u.VerbosityDetailsLevel, other.VerbosityDetailsLevel)
+	u.ValidationLogLevel = gosettings.MergeWithPointer(u.ValidationLogLevel, other.ValidationLogLevel)
+	u.Username = gosettings.MergeWithString(u.Username, other.Username)
+	u.Allowed = gosettings.MergeWithSlice(u.Allowed, other.Allowed)
 }
 
 func (u *Unbound) overrideWith(other Unbound) {
-	u.Providers = helpers.OverrideWithStringSlice(u.Providers, other.Providers)
-	u.Caching = helpers.OverrideWithBool(u.Caching, other.Caching)
-	u.IPv6 = helpers.OverrideWithBool(u.IPv6, other.IPv6)
-	u.VerbosityLevel = helpers.OverrideWithUint8(u.VerbosityLevel, other.VerbosityLevel)
-	u.VerbosityDetailsLevel = helpers.OverrideWithUint8(u.VerbosityDetailsLevel, other.VerbosityDetailsLevel)
-	u.ValidationLogLevel = helpers.OverrideWithUint8(u.ValidationLogLevel, other.ValidationLogLevel)
-	u.Username = helpers.OverrideWithString(u.Username, other.Username)
-	u.Allowed = helpers.OverrideWithIPPrefixesSlice(u.Allowed, other.Allowed)
+	u.Providers = gosettings.OverrideWithSlice(u.Providers, other.Providers)
+	u.Caching = gosettings.OverrideWithPointer(u.Caching, other.Caching)
+	u.IPv6 = gosettings.OverrideWithPointer(u.IPv6, other.IPv6)
+	u.VerbosityLevel = gosettings.OverrideWithPointer(u.VerbosityLevel, other.VerbosityLevel)
+	u.VerbosityDetailsLevel = gosettings.OverrideWithPointer(u.VerbosityDetailsLevel, other.VerbosityDetailsLevel)
+	u.ValidationLogLevel = gosettings.OverrideWithPointer(u.ValidationLogLevel, other.ValidationLogLevel)
+	u.Username = gosettings.OverrideWithString(u.Username, other.Username)
+	u.Allowed = gosettings.OverrideWithSlice(u.Allowed, other.Allowed)
 }
 
 func (u Unbound) ToUnboundFormat() (settings unbound.Settings, err error) {
@@ -149,20 +148,30 @@ func (u Unbound) ToUnboundFormat() (settings unbound.Settings, err error) {
 		VerbosityDetailsLevel: *u.VerbosityDetailsLevel,
 		ValidationLogLevel:    *u.ValidationLogLevel,
 		AccessControl: unbound.AccessControlSettings{
-			Allowed: u.Allowed,
+			Allowed: netipPrefixesToNetaddrIPPrefixes(u.Allowed),
 		},
 		Username: u.Username,
 	}, nil
 }
 
-func (u Unbound) GetFirstPlaintextIPv4() (ipv4 net.IP, err error) {
+var (
+	ErrConvertingNetip = errors.New("converting net.IP to netip.Addr failed")
+)
+
+func (u Unbound) GetFirstPlaintextIPv4() (ipv4 netip.Addr, err error) {
 	s := u.Providers[0]
 	provider, err := provider.Parse(s)
 	if err != nil {
-		return nil, err
+		return ipv4, err
 	}
 
-	return provider.DNS().IPv4[0], nil
+	ip := provider.DNS().IPv4[0]
+	ipv4, ok := netip.AddrFromSlice(ip)
+	if !ok {
+		return ipv4, fmt.Errorf("%w: for ip %s (%#v)",
+			ErrConvertingNetip, ip, ip)
+	}
+	return ipv4.Unmap(), nil
 }
 
 func (u Unbound) String() string {
@@ -177,8 +186,8 @@ func (u Unbound) toLinesNode() (node *gotree.Node) {
 		authServers.Appendf(provider)
 	}
 
-	node.Appendf("Caching: %s", helpers.BoolPtrToYesNo(u.Caching))
-	node.Appendf("IPv6: %s", helpers.BoolPtrToYesNo(u.IPv6))
+	node.Appendf("Caching: %s", gosettings.BoolToYesNo(u.Caching))
+	node.Appendf("IPv6: %s", gosettings.BoolToYesNo(u.IPv6))
 	node.Appendf("Verbosity level: %d", *u.VerbosityLevel)
 	node.Appendf("Verbosity details level: %d", *u.VerbosityDetailsLevel)
 	node.Appendf("Validation log level: %d", *u.ValidationLogLevel)

internal/configuration/settings/unbound_test.go

@@ -2,11 +2,11 @@ package settings
 
 import (
 	"encoding/json"
+	"net/netip"
 	"testing"
 
 	"github.com/stretchr/testify/assert"
 	"github.com/stretchr/testify/require"
-	"inet.af/netaddr"
 )
 
 func Test_Unbound_JSON(t *testing.T) {
@@ -20,18 +20,18 @@ func Test_Unbound_JSON(t *testing.T) {
 		VerbosityDetailsLevel: nil,
 		ValidationLogLevel:    uint8Ptr(0),
 		Username:              "user",
-		Allowed: []netaddr.IPPrefix{
-			netaddr.IPPrefixFrom(netaddr.IPv4(0, 0, 0, 0), 0),
-			netaddr.IPPrefixFrom(netaddr.IPv6Raw([16]byte{}), 0),
+		Allowed: []netip.Prefix{
+			netip.PrefixFrom(netip.AddrFrom4([4]byte{}), 0),
+			netip.PrefixFrom(netip.AddrFrom16([16]byte{}), 0),
 		},
 	}
 
 	b, err := json.Marshal(settings)
 	require.NoError(t, err)
 
-	const expected = `{"Providers":["cloudflare"],"Caching":true,"IPv6":false,` +
-		`"VerbosityLevel":1,"VerbosityDetailsLevel":null,"ValidationLogLevel":0,` +
-		`"Username":"user","Allowed":["0.0.0.0/0","::/0"]}`
+	const expected = `{"providers":["cloudflare"],"caching":true,"ipv6":false,` +
+		`"verbosity_level":1,"verbosity_details_level":null,"validation_log_level":0,` +
+		`"username":"user","allowed":["0.0.0.0/0","::/0"]}`
 
 	assert.Equal(t, expected, string(b))
 

internal/configuration/settings/updater.go

@@ -5,8 +5,9 @@ import (
 	"strings"
 	"time"
 
-	"github.com/qdm12/gluetun/internal/configuration/settings/helpers"
 	"github.com/qdm12/gluetun/internal/constants/providers"
+	"github.com/qdm12/gosettings"
+	"github.com/qdm12/gosettings/validate"
 	"github.com/qdm12/gotree"
 )
 
@@ -45,16 +46,9 @@ func (u Updater) Validate() (err error) {
 
 	validProviders := providers.All()
 	for _, provider := range u.Providers {
-		valid := false
-		for _, validProvider := range validProviders {
-			if provider == validProvider {
-				valid = true
-				break
-			}
-		}
-		if !valid {
-			return fmt.Errorf("%w: %q can only be one of %s",
-				ErrVPNProviderNameNotValid, provider, helpers.ChoicesOrString(validProviders))
+		err = validate.IsOneOf(provider, validProviders...)
+		if err != nil {
+			return fmt.Errorf("%w: %w", ErrVPNProviderNameNotValid, err)
 		}
 	}
 
@@ -63,35 +57,35 @@ func (u Updater) Validate() (err error) {
 
 func (u *Updater) copy() (copied Updater) {
 	return Updater{
-		Period:     helpers.CopyDurationPtr(u.Period),
+		Period:     gosettings.CopyPointer(u.Period),
 		DNSAddress: u.DNSAddress,
 		MinRatio:   u.MinRatio,
-		Providers:  helpers.CopyStringSlice(u.Providers),
+		Providers:  gosettings.CopySlice(u.Providers),
 	}
 }
 
 // mergeWith merges the other settings into any
 // unset field of the receiver settings object.
 func (u *Updater) mergeWith(other Updater) {
-	u.Period = helpers.MergeWithDuration(u.Period, other.Period)
-	u.DNSAddress = helpers.MergeWithString(u.DNSAddress, other.DNSAddress)
-	u.MinRatio = helpers.MergeWithFloat64(u.MinRatio, other.MinRatio)
-	u.Providers = helpers.MergeStringSlices(u.Providers, other.Providers)
+	u.Period = gosettings.MergeWithPointer(u.Period, other.Period)
+	u.DNSAddress = gosettings.MergeWithString(u.DNSAddress, other.DNSAddress)
+	u.MinRatio = gosettings.MergeWithNumber(u.MinRatio, other.MinRatio)
+	u.Providers = gosettings.MergeWithSlice(u.Providers, other.Providers)
 }
 
 // overrideWith overrides fields of the receiver
 // settings object with any field set in the other
 // settings.
 func (u *Updater) overrideWith(other Updater) {
-	u.Period = helpers.OverrideWithDuration(u.Period, other.Period)
-	u.DNSAddress = helpers.OverrideWithString(u.DNSAddress, other.DNSAddress)
-	u.MinRatio = helpers.OverrideWithFloat64(u.MinRatio, other.MinRatio)
-	u.Providers = helpers.OverrideWithStringSlice(u.Providers, other.Providers)
+	u.Period = gosettings.OverrideWithPointer(u.Period, other.Period)
+	u.DNSAddress = gosettings.OverrideWithString(u.DNSAddress, other.DNSAddress)
+	u.MinRatio = gosettings.OverrideWithNumber(u.MinRatio, other.MinRatio)
+	u.Providers = gosettings.OverrideWithSlice(u.Providers, other.Providers)
 }
 
 func (u *Updater) SetDefaults(vpnProvider string) {
-	u.Period = helpers.DefaultDuration(u.Period, 0)
-	u.DNSAddress = helpers.DefaultString(u.DNSAddress, "1.1.1.1:53")
+	u.Period = gosettings.DefaultPointer(u.Period, 0)
+	u.DNSAddress = gosettings.DefaultString(u.DNSAddress, "1.1.1.1:53")
 
 	if u.MinRatio == 0 {
 		const defaultMinRatio = 0.8

internal/configuration/settings/validation/servers.go

@@ -33,6 +33,28 @@ func ExtractCountries(servers []models.Server) (values []string) {
 	return values
 }
 
+func ExtractCategories(servers []models.Server) (values []string) {
+	seen := make(map[string]struct{}, len(servers))
+	values = make([]string, 0, len(servers))
+	for _, server := range servers {
+		categories := server.Categories
+		if len(categories) == 0 {
+			continue
+		}
+
+		for _, value := range categories {
+			_, alreadySeen := seen[value]
+			if alreadySeen {
+				continue
+			}
+			seen[value] = struct{}{}
+
+			values = sortedInsert(values, value)
+		}
+	}
+	return values
+}
+
 func ExtractRegions(servers []models.Server) (values []string) {
 	seen := make(map[string]struct{}, len(servers))
 	values = make([]string, 0, len(servers))

internal/configuration/settings/validation/surfshark.go

@@ -10,6 +10,9 @@ func SurfsharkRetroLocChoices() (choices []string) {
 	choices = make([]string, 0, len(locationData))
 	seen := make(map[string]struct{}, len(locationData))
 	for _, data := range locationData {
+		if data.RetroLoc == "" {
+			continue
+		}
 		if _, ok := seen[data.RetroLoc]; ok {
 			continue
 		}

internal/configuration/settings/version.go

@@ -1,7 +1,7 @@
 package settings
 
 import (
-	"github.com/qdm12/gluetun/internal/configuration/settings/helpers"
+	"github.com/qdm12/gosettings"
 	"github.com/qdm12/gotree"
 )
 
@@ -19,25 +19,25 @@ func (v Version) validate() (err error) {
 
 func (v *Version) copy() (copied Version) {
 	return Version{
-		Enabled: helpers.CopyBoolPtr(v.Enabled),
+		Enabled: gosettings.CopyPointer(v.Enabled),
 	}
 }
 
 // mergeWith merges the other settings into any
 // unset field of the receiver settings object.
 func (v *Version) mergeWith(other Version) {
-	v.Enabled = helpers.MergeWithBool(v.Enabled, other.Enabled)
+	v.Enabled = gosettings.MergeWithPointer(v.Enabled, other.Enabled)
 }
 
 // overrideWith overrides fields of the receiver
 // settings object with any field set in the other
 // settings.
 func (v *Version) overrideWith(other Version) {
-	v.Enabled = helpers.OverrideWithBool(v.Enabled, other.Enabled)
+	v.Enabled = gosettings.OverrideWithPointer(v.Enabled, other.Enabled)
 }
 
 func (v *Version) setDefaults() {
-	v.Enabled = helpers.DefaultBool(v.Enabled, true)
+	v.Enabled = gosettings.DefaultPointer(v.Enabled, true)
 }
 
 func (v Version) String() string {
@@ -47,7 +47,7 @@ func (v Version) String() string {
 func (v Version) toLinesNode() (node *gotree.Node) {
 	node = gotree.New("Version settings:")
 
-	node.Appendf("Enabled: %s", helpers.BoolPtrToYesNo(v.Enabled))
+	node.Appendf("Enabled: %s", gosettings.BoolToYesNo(v.Enabled))
 
 	return node
 }

internal/configuration/settings/vpn.go

@@ -2,10 +2,10 @@ package settings
 
 import (
 	"fmt"
-	"strings"
 
-	"github.com/qdm12/gluetun/internal/configuration/settings/helpers"
 	"github.com/qdm12/gluetun/internal/constants/vpn"
+	"github.com/qdm12/gosettings"
+	"github.com/qdm12/gosettings/validate"
 	"github.com/qdm12/gotree"
 )
 
@@ -13,19 +13,18 @@ type VPN struct {
 	// Type is the VPN type and can only be
 	// 'openvpn' or 'wireguard'. It cannot be the
 	// empty string in the internal state.
-	Type      string
-	Provider  Provider
-	OpenVPN   OpenVPN
-	Wireguard Wireguard
+	Type      string    `json:"type"`
+	Provider  Provider  `json:"provider"`
+	OpenVPN   OpenVPN   `json:"openvpn"`
+	Wireguard Wireguard `json:"wireguard"`
 }
 
 // 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...) {
-		return fmt.Errorf("%w: %q and can only be one of %s",
-			ErrVPNTypeNotValid, v.Type, strings.Join(validVPNTypes, ", "))
+	if err = validate.IsOneOf(v.Type, validVPNTypes...); err != nil {
+		return fmt.Errorf("%w: %w", ErrVPNTypeNotValid, err)
 	}
 
 	err = v.Provider.validate(v.Type, storage)
@@ -39,7 +38,7 @@ 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)
 		}
@@ -48,7 +47,7 @@ func (v *VPN) validate(storage Storage) (err error) {
 	return nil
 }
 
-func (v *VPN) copy() (copied VPN) {
+func (v *VPN) Copy() (copied VPN) {
 	return VPN{
 		Type:      v.Type,
 		Provider:  v.Provider.copy(),
@@ -58,24 +57,24 @@ func (v *VPN) copy() (copied VPN) {
 }
 
 func (v *VPN) mergeWith(other VPN) {
-	v.Type = helpers.MergeWithString(v.Type, other.Type)
+	v.Type = gosettings.MergeWithString(v.Type, other.Type)
 	v.Provider.mergeWith(other.Provider)
 	v.OpenVPN.mergeWith(other.OpenVPN)
 	v.Wireguard.mergeWith(other.Wireguard)
 }
 
-func (v *VPN) overrideWith(other VPN) {
-	v.Type = helpers.OverrideWithString(v.Type, other.Type)
+func (v *VPN) OverrideWith(other VPN) {
+	v.Type = gosettings.OverrideWithString(v.Type, other.Type)
 	v.Provider.overrideWith(other.Provider)
 	v.OpenVPN.overrideWith(other.OpenVPN)
 	v.Wireguard.overrideWith(other.Wireguard)
 }
 
 func (v *VPN) setDefaults() {
-	v.Type = helpers.DefaultString(v.Type, vpn.OpenVPN)
+	v.Type = gosettings.DefaultString(v.Type, vpn.OpenVPN)
 	v.Provider.setDefaults()
 	v.OpenVPN.setDefaults(*v.Provider.Name)
-	v.Wireguard.setDefaults()
+	v.Wireguard.setDefaults(*v.Provider.Name)
 }
 
 func (v VPN) String() string {

internal/configuration/settings/wireguard.go

@@ -2,11 +2,13 @@ package settings
 
 import (
 	"fmt"
-	"net"
+	"net/netip"
 	"regexp"
 
 	"github.com/qdm12/gluetun/internal/configuration/settings/helpers"
 	"github.com/qdm12/gluetun/internal/constants/providers"
+	"github.com/qdm12/gosettings"
+	"github.com/qdm12/gosettings/validate"
 	"github.com/qdm12/gotree"
 	"golang.zx2c4.com/wireguard/wgctrl/wgtypes"
 )
@@ -15,29 +17,47 @@ import (
 type Wireguard struct {
 	// PrivateKey is the Wireguard client peer private key.
 	// It cannot be nil in the internal state.
-	PrivateKey *string
+	PrivateKey *string `json:"private_key"`
 	// PreSharedKey is the Wireguard pre-shared key.
 	// It can be the empty string to indicate there
 	// is no pre-shared key.
 	// It cannot be nil in the internal state.
-	PreSharedKey *string
+	PreSharedKey *string `json:"pre_shared_key"`
 	// Addresses are the Wireguard interface addresses.
-	Addresses []net.IPNet
+	Addresses []netip.Prefix `json:"addresses"`
+	// AllowedIPs are the Wireguard allowed IPs.
+	// If left unset, they default to "0.0.0.0/0"
+	// and, if IPv6 is supported, "::0".
+	AllowedIPs []netip.Prefix `json:"allowed_ips"`
 	// Interface is the name of the Wireguard interface
 	// to create. It cannot be the empty string in the
 	// internal state.
-	Interface string
+	Interface string `json:"interface"`
+	// Maximum Transmission Unit (MTU) of the Wireguard interface.
+	// It cannot be zero in the internal state, and defaults to
+	// 1400. Note it is not the wireguard-go MTU default of 1420
+	// because this impacts bandwidth a lot on some VPN providers,
+	// see https://github.com/qdm12/gluetun/issues/1650.
+	MTU uint16 `json:"mtu"`
+	// 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 `json:"implementation"`
 }
 
 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.Airvpn,
 		providers.Custom,
 		providers.Ivpn,
 		providers.Mullvad,
+		providers.Nordvpn,
+		providers.Surfshark,
 		providers.Windscribe,
 	) {
 		// do not validate for VPN provider not supporting Wireguard
@@ -46,11 +66,22 @@ func (w Wireguard) validate(vpnProvider string) (err error) {
 
 	// Validate PrivateKey
 	if *w.PrivateKey == "" {
-		return ErrWireguardPrivateKeyNotSet
+		return fmt.Errorf("%w", ErrWireguardPrivateKeyNotSet)
 	}
 	_, err = wgtypes.ParseKey(*w.PrivateKey)
 	if err != nil {
-		return fmt.Errorf("private key is not valid: %w", err)
+		err = fmt.Errorf("private key is not valid: %w", err)
+		if vpnProvider == providers.Nordvpn &&
+			err.Error() == "wgtypes: incorrect key size: 48" {
+			err = fmt.Errorf("%w - you might be using your access token instead of the Wireguard private key", err)
+		}
+		return err
+	}
+
+	if vpnProvider == providers.Airvpn {
+		if *w.PreSharedKey == "" {
+			return fmt.Errorf("%w", ErrWireguardPreSharedKeyNotSet)
+		}
 	}
 
 	// Validate PreSharedKey
@@ -63,12 +94,30 @@ func (w Wireguard) validate(vpnProvider string) (err error) {
 
 	// Validate Addresses
 	if len(w.Addresses) == 0 {
-		return ErrWireguardInterfaceAddressNotSet
+		return fmt.Errorf("%w", ErrWireguardInterfaceAddressNotSet)
 	}
 	for i, ipNet := range w.Addresses {
-		if ipNet.IP == nil || ipNet.Mask == nil {
-			return fmt.Errorf("%w: for address at index %d: %s",
-				ErrWireguardInterfaceAddressNotSet, i, ipNet.String())
+		if !ipNet.IsValid() {
+			return fmt.Errorf("%w: for address at index %d",
+				ErrWireguardInterfaceAddressNotSet, i)
+		}
+
+		if !ipv6Supported && ipNet.Addr().Is6() {
+			return fmt.Errorf("%w: address %s",
+				ErrWireguardInterfaceAddressIPv6, ipNet.String())
+		}
+	}
+
+	// Validate AllowedIPs
+	// WARNING: do not check for IPv6 networks in the allowed IPs,
+	// the wireguard code will take care to ignore it.
+	if len(w.AllowedIPs) == 0 {
+		return fmt.Errorf("%w", ErrWireguardAllowedIPsNotSet)
+	}
+	for i, allowedIP := range w.AllowedIPs {
+		if !allowedIP.IsValid() {
+			return fmt.Errorf("%w: for allowed ip %d of %d",
+				ErrWireguardAllowedIPNotSet, i+1, len(w.AllowedIPs))
 		}
 	}
 
@@ -78,36 +127,63 @@ func (w Wireguard) validate(vpnProvider string) (err error) {
 			ErrWireguardInterfaceNotValid, w.Interface, regexpInterfaceName)
 	}
 
+	validImplementations := []string{"auto", "userspace", "kernelspace"}
+	if err := validate.IsOneOf(w.Implementation, validImplementations...); err != nil {
+		return fmt.Errorf("%w: %w", ErrWireguardImplementationNotValid, err)
+	}
+
 	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:     gosettings.CopyPointer(w.PrivateKey),
+		PreSharedKey:   gosettings.CopyPointer(w.PreSharedKey),
+		Addresses:      gosettings.CopySlice(w.Addresses),
+		AllowedIPs:     gosettings.CopySlice(w.AllowedIPs),
+		Interface:      w.Interface,
+		MTU:            w.MTU,
+		Implementation: w.Implementation,
 	}
 }
 
 func (w *Wireguard) mergeWith(other Wireguard) {
-	w.PrivateKey = helpers.MergeWithStringPtr(w.PrivateKey, other.PrivateKey)
-	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.PrivateKey = gosettings.MergeWithPointer(w.PrivateKey, other.PrivateKey)
+	w.PreSharedKey = gosettings.MergeWithPointer(w.PreSharedKey, other.PreSharedKey)
+	w.Addresses = gosettings.MergeWithSlice(w.Addresses, other.Addresses)
+	w.AllowedIPs = gosettings.MergeWithSlice(w.AllowedIPs, other.AllowedIPs)
+	w.Interface = gosettings.MergeWithString(w.Interface, other.Interface)
+	w.MTU = gosettings.MergeWithNumber(w.MTU, other.MTU)
+	w.Implementation = gosettings.MergeWithString(w.Implementation, other.Implementation)
 }
 
 func (w *Wireguard) overrideWith(other Wireguard) {
-	w.PrivateKey = helpers.OverrideWithStringPtr(w.PrivateKey, other.PrivateKey)
-	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.PrivateKey = gosettings.OverrideWithPointer(w.PrivateKey, other.PrivateKey)
+	w.PreSharedKey = gosettings.OverrideWithPointer(w.PreSharedKey, other.PreSharedKey)
+	w.Addresses = gosettings.OverrideWithSlice(w.Addresses, other.Addresses)
+	w.AllowedIPs = gosettings.OverrideWithSlice(w.AllowedIPs, other.AllowedIPs)
+	w.Interface = gosettings.OverrideWithString(w.Interface, other.Interface)
+	w.MTU = gosettings.OverrideWithNumber(w.MTU, other.MTU)
+	w.Implementation = gosettings.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")
+func (w *Wireguard) setDefaults(vpnProvider string) {
+	w.PrivateKey = gosettings.DefaultPointer(w.PrivateKey, "")
+	w.PreSharedKey = gosettings.DefaultPointer(w.PreSharedKey, "")
+	if vpnProvider == providers.Nordvpn {
+		defaultNordVPNAddress := netip.AddrFrom4([4]byte{10, 5, 0, 2})
+		defaultNordVPNPrefix := netip.PrefixFrom(defaultNordVPNAddress, defaultNordVPNAddress.BitLen())
+		w.Addresses = gosettings.DefaultSlice(w.Addresses, []netip.Prefix{defaultNordVPNPrefix})
+	}
+	defaultAllowedIPs := []netip.Prefix{
+		netip.PrefixFrom(netip.IPv4Unspecified(), 0),
+		netip.PrefixFrom(netip.IPv6Unspecified(), 0),
+	}
+	w.AllowedIPs = gosettings.DefaultSlice(w.AllowedIPs, defaultAllowedIPs)
+	w.Interface = gosettings.DefaultString(w.Interface, "wg0")
+	const defaultMTU = 1400
+	w.MTU = gosettings.DefaultNumber(w.MTU, defaultMTU)
+	w.Implementation = gosettings.DefaultString(w.Implementation, "auto")
 }
 
 func (w Wireguard) String() string {
@@ -118,12 +194,12 @@ func (w Wireguard) toLinesNode() (node *gotree.Node) {
 	node = gotree.New("Wireguard settings:")
 
 	if *w.PrivateKey != "" {
-		s := helpers.ObfuscateWireguardKey(*w.PrivateKey)
+		s := gosettings.ObfuscateKey(*w.PrivateKey)
 		node.Appendf("Private key: %s", s)
 	}
 
 	if *w.PreSharedKey != "" {
-		s := helpers.ObfuscateWireguardKey(*w.PreSharedKey)
+		s := gosettings.ObfuscateKey(*w.PreSharedKey)
 		node.Appendf("Pre-shared key: %s", s)
 	}
 
@@ -132,7 +208,17 @@ func (w Wireguard) toLinesNode() (node *gotree.Node) {
 		addressesNode.Appendf(address.String())
 	}
 
-	node.Appendf("Network interface: %s", w.Interface)
+	allowedIPsNode := node.Appendf("Allowed IPs:")
+	for _, allowedIP := range w.AllowedIPs {
+		allowedIPsNode.Appendf(allowedIP.String())
+	}
+
+	interfaceNode := node.Appendf("Network interface: %s", w.Interface)
+	interfaceNode.Appendf("MTU: %d", w.MTU)
+
+	if w.Implementation != "auto" {
+		node.Appendf("Implementation: %s", w.Implementation)
+	}
 
 	return node
 }

internal/configuration/settings/wireguardselection.go

@@ -2,10 +2,11 @@ package settings
 
 import (
 	"fmt"
-	"net"
+	"net/netip"
 
-	"github.com/qdm12/gluetun/internal/configuration/settings/helpers"
 	"github.com/qdm12/gluetun/internal/constants/providers"
+	"github.com/qdm12/gosettings"
+	"github.com/qdm12/gosettings/validate"
 	"github.com/qdm12/gotree"
 	"golang.zx2c4.com/wireguard/wgctrl/wgtypes"
 )
@@ -15,20 +16,20 @@ type WireguardSelection struct {
 	// It is only used with VPN providers generating Wireguard
 	// configurations specific to each server and user.
 	// To indicate it should not be used, it should be set
-	// to the empty net.IP{} slice. It can never be nil
+	// to netip.IPv4Unspecified(). It can never be the zero value
 	// in the internal state.
-	EndpointIP net.IP
+	EndpointIP netip.Addr `json:"endpoint_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
 	// state.
-	EndpointPort *uint16
+	EndpointPort *uint16 `json:"endpoint_port"`
 	// PublicKey is the server public key.
 	// It is only used with VPN providers generating Wireguard
 	// configurations specific to each server and user.
-	PublicKey string
+	PublicKey string `json:"public_key"`
 }
 
 // Validate validates WireguardSelection settings.
@@ -36,10 +37,12 @@ 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.Nordvpn, providers.Surfshark, providers.Windscribe:
+		// endpoint IP addresses are baked in
 	case providers.Custom:
-		if len(w.EndpointIP) == 0 {
-			return ErrWireguardEndpointIPNotSet
+		if !w.EndpointIP.IsValid() || w.EndpointIP.IsUnspecified() {
+			return fmt.Errorf("%w", ErrWireguardEndpointIPNotSet)
 		}
 	default: // Providers not supporting Wireguard
 	}
@@ -49,9 +52,14 @@ func (w WireguardSelection) validate(vpnProvider string) (err error) {
 	// EndpointPort is required
 	case providers.Custom:
 		if *w.EndpointPort == 0 {
-			return ErrWireguardEndpointPortNotSet
+			return fmt.Errorf("%w", ErrWireguardEndpointPortNotSet)
 		}
-	case providers.Ivpn, providers.Mullvad, providers.Windscribe:
+	// EndpointPort cannot be set
+	case providers.Surfshark, providers.Nordvpn:
+		if *w.EndpointPort != 0 {
+			return fmt.Errorf("%w", 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
@@ -61,27 +69,31 @@ 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:
 			allowed = []uint16{53, 80, 123, 443, 1194, 65142}
 		}
 
-		if helpers.Uint16IsOneOf(*w.EndpointPort, allowed) {
+		err = validate.IsOneOf(*w.EndpointPort, allowed...)
+		if err == nil {
 			break
 		}
-		return fmt.Errorf("%w: %d for VPN service provider %s; %s",
-			ErrWireguardEndpointPortNotAllowed, w.EndpointPort, vpnProvider,
-			helpers.PortChoicesOrString(allowed))
+		return fmt.Errorf("%w: for VPN service provider %s: %w",
+			ErrWireguardEndpointPortNotAllowed, vpnProvider, err)
 	default: // Providers not supporting Wireguard
 	}
 
 	// 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
+			return fmt.Errorf("%w", ErrWireguardPublicKeyNotSet)
 		}
 	default: // Providers not supporting Wireguard
 	}
@@ -98,27 +110,27 @@ func (w WireguardSelection) validate(vpnProvider string) (err error) {
 
 func (w *WireguardSelection) copy() (copied WireguardSelection) {
 	return WireguardSelection{
-		EndpointIP:   helpers.CopyIP(w.EndpointIP),
-		EndpointPort: helpers.CopyUint16Ptr(w.EndpointPort),
+		EndpointIP:   w.EndpointIP,
+		EndpointPort: gosettings.CopyPointer(w.EndpointPort),
 		PublicKey:    w.PublicKey,
 	}
 }
 
 func (w *WireguardSelection) mergeWith(other WireguardSelection) {
-	w.EndpointIP = helpers.MergeWithIP(w.EndpointIP, other.EndpointIP)
-	w.EndpointPort = helpers.MergeWithUint16(w.EndpointPort, other.EndpointPort)
-	w.PublicKey = helpers.MergeWithString(w.PublicKey, other.PublicKey)
+	w.EndpointIP = gosettings.MergeWithValidator(w.EndpointIP, other.EndpointIP)
+	w.EndpointPort = gosettings.MergeWithPointer(w.EndpointPort, other.EndpointPort)
+	w.PublicKey = gosettings.MergeWithString(w.PublicKey, other.PublicKey)
 }
 
 func (w *WireguardSelection) overrideWith(other WireguardSelection) {
-	w.EndpointIP = helpers.OverrideWithIP(w.EndpointIP, other.EndpointIP)
-	w.EndpointPort = helpers.OverrideWithUint16(w.EndpointPort, other.EndpointPort)
-	w.PublicKey = helpers.OverrideWithString(w.PublicKey, other.PublicKey)
+	w.EndpointIP = gosettings.OverrideWithValidator(w.EndpointIP, other.EndpointIP)
+	w.EndpointPort = gosettings.OverrideWithPointer(w.EndpointPort, other.EndpointPort)
+	w.PublicKey = gosettings.OverrideWithString(w.PublicKey, other.PublicKey)
 }
 
 func (w *WireguardSelection) setDefaults() {
-	w.EndpointIP = helpers.DefaultIP(w.EndpointIP, net.IP{})
-	w.EndpointPort = helpers.DefaultUint16(w.EndpointPort, 0)
+	w.EndpointIP = gosettings.DefaultValidator(w.EndpointIP, netip.IPv4Unspecified())
+	w.EndpointPort = gosettings.DefaultPointer(w.EndpointPort, 0)
 }
 
 func (w WireguardSelection) String() string {
@@ -128,7 +140,7 @@ func (w WireguardSelection) String() string {
 func (w WireguardSelection) toLinesNode() (node *gotree.Node) {
 	node = gotree.New("Wireguard selection settings:")
 
-	if len(w.EndpointIP) > 0 {
+	if !w.EndpointIP.IsUnspecified() {
 		node.Appendf("Endpoint IP address: %s", w.EndpointIP)
 	}
 

internal/configuration/sources/env/dns.go

@@ -2,23 +2,23 @@ package env
 
 import (
 	"fmt"
-	"net"
+	"net/netip"
 
 	"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
 	}
 
-	dns.KeepNameserver, err = envToBoolPtr("DNS_KEEP_NAMESERVER")
+	dns.KeepNameserver, err = s.env.BoolPtr("DNS_KEEP_NAMESERVER")
 	if err != nil {
-		return dns, fmt.Errorf("environment variable DNS_KEEP_NAMESERVER: %w", err)
+		return dns, err
 	}
 
-	dns.DoT, err = r.readDoT()
+	dns.DoT, err = s.readDoT()
 	if err != nil {
 		return dns, fmt.Errorf("DoT settings: %w", err)
 	}
@@ -26,22 +26,27 @@ 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 == "" {
-		return nil, nil
+func (s *Source) readDNSServerAddress() (address netip.Addr, err error) {
+	const currentKey = "DNS_ADDRESS"
+	key := firstKeySet(s.env, "DNS_PLAINTEXT_ADDRESS", currentKey)
+	switch key {
+	case "":
+		return address, nil
+	case currentKey:
+	default: // Retro-compatibility
+		s.handleDeprecatedKey(key, currentKey)
 	}
 
-	address = net.ParseIP(s)
-	if address == nil {
-		return nil, fmt.Errorf("environment variable %s: %w: %s", key, ErrIPAddressParse, s)
+	address, err = s.env.NetipAddr(key)
+	if err != nil {
+		return address, err
 	}
 
 	// TODO remove in v4
-	if !address.Equal(net.IPv4(127, 0, 0, 1)) { //nolint:gomnd
-		r.warner.Warn(key + " is set to " + s +
+	if address.Unmap().Compare(netip.AddrFrom4([4]byte{127, 0, 0, 1})) != 0 {
+		s.warner.Warn(key + " is set to " + address.String() +
 			" 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

@@ -3,76 +3,62 @@ package env
 import (
 	"errors"
 	"fmt"
+	"net/netip"
 
 	"github.com/qdm12/gluetun/internal/configuration/settings"
-	"github.com/qdm12/govalid/binary"
-	"inet.af/netaddr"
+	"github.com/qdm12/gosettings/sources/env"
 )
 
-func (r *Reader) 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()
+func (s *Source) readDNSBlacklist() (blacklist settings.DNSBlacklist, err error) {
+	blacklist.BlockMalicious, err = s.env.BoolPtr("BLOCK_MALICIOUS")
 	if err != nil {
 		return blacklist, err
 	}
 
-	blacklist.BlockAds, err = envToBoolPtr("BLOCK_ADS")
+	blacklist.BlockSurveillance, err = s.env.BoolPtr("BLOCK_SURVEILLANCE",
+		env.RetroKeys("BLOCK_NSA"))
 	if err != nil {
-		return blacklist, fmt.Errorf("environment variable BLOCK_ADS: %w", err)
+		return blacklist, err
+	}
+
+	blacklist.BlockAds, err = s.env.BoolPtr("BLOCK_ADS")
+	if err != nil {
+		return blacklist, err
 	}
 
 	blacklist.AddBlockedIPs, blacklist.AddBlockedIPPrefixes,
-		err = readDoTPrivateAddresses() // TODO v4 split in 2
+		err = s.readDoTPrivateAddresses() // TODO v4 split in 2
 	if err != nil {
 		return blacklist, err
 	}
 
-	blacklist.AllowedHosts = envToCSV("UNBLOCK") // TODO v4 change name
+	blacklist.AllowedHosts = s.env.CSV("UNBLOCK") // TODO v4 change name
 
 	return blacklist, nil
 }
 
-func (r *Reader) readBlockSurveillance() (blocked *bool, err error) {
-	key, value := r.getEnvWithRetro("BLOCK_SURVEILLANCE", "BLOCK_NSA")
-	if value == "" {
-		return nil, nil //nolint:nilnil
-	}
-
-	blocked = new(bool)
-	*blocked, err = binary.Validate(value)
-	if err != nil {
-		return nil, fmt.Errorf("environment variable %s: %w", key, err)
-	}
-
-	return blocked, nil
-}
-
 var (
 	ErrPrivateAddressNotValid = errors.New("private address is not a valid IP or CIDR range")
 )
 
-func readDoTPrivateAddresses() (ips []netaddr.IP,
-	ipPrefixes []netaddr.IPPrefix, err error) {
-	privateAddresses := envToCSV("DOT_PRIVATE_ADDRESS")
+func (s *Source) readDoTPrivateAddresses() (ips []netip.Addr,
+	ipPrefixes []netip.Prefix, err error) {
+	privateAddresses := s.env.CSV("DOT_PRIVATE_ADDRESS")
 	if len(privateAddresses) == 0 {
 		return nil, nil, nil
 	}
 
-	ips = make([]netaddr.IP, 0, len(privateAddresses))
-	ipPrefixes = make([]netaddr.IPPrefix, 0, len(privateAddresses))
+	ips = make([]netip.Addr, 0, len(privateAddresses))
+	ipPrefixes = make([]netip.Prefix, 0, len(privateAddresses))
 
 	for _, privateAddress := range privateAddresses {
-		ip, err := netaddr.ParseIP(privateAddress)
+		ip, err := netip.ParseAddr(privateAddress)
 		if err == nil {
 			ips = append(ips, ip)
 			continue
 		}
 
-		ipPrefix, err := netaddr.ParseIPPrefix(privateAddress)
+		ipPrefix, err := netip.ParsePrefix(privateAddress)
 		if err == nil {
 			ipPrefixes = append(ipPrefixes, ipPrefix)
 			continue

internal/configuration/sources/env/dot.go

@@ -1,28 +1,26 @@
 package env
 
 import (
-	"fmt"
-
 	"github.com/qdm12/gluetun/internal/configuration/settings"
 )
 
-func (r *Reader) readDoT() (dot settings.DoT, err error) {
-	dot.Enabled, err = envToBoolPtr("DOT")
-	if err != nil {
-		return dot, fmt.Errorf("environment variable DOT: %w", err)
-	}
-
-	dot.UpdatePeriod, err = envToDurationPtr("DNS_UPDATE_PERIOD")
-	if err != nil {
-		return dot, fmt.Errorf("environment variable DNS_UPDATE_PERIOD: %w", err)
-	}
-
-	dot.Unbound, err = readUnbound()
+func (s *Source) readDoT() (dot settings.DoT, err error) {
+	dot.Enabled, err = s.env.BoolPtr("DOT")
 	if err != nil {
 		return dot, err
 	}
 
-	dot.Blacklist, err = r.readDNSBlacklist()
+	dot.UpdatePeriod, err = s.env.DurationPtr("DNS_UPDATE_PERIOD")
+	if err != nil {
+		return dot, err
+	}
+
+	dot.Unbound, err = s.readUnbound()
+	if err != nil {
+		return dot, err
+	}
+
+	dot.Blacklist, err = s.readDNSBlacklist()
 	if err != nil {
 		return dot, err
 	}

internal/configuration/sources/env/firewall.go

@@ -1,82 +1,36 @@
 package env
 
 import (
-	"errors"
-	"fmt"
-	"net"
-	"strconv"
-
 	"github.com/qdm12/gluetun/internal/configuration/settings"
+	"github.com/qdm12/gosettings/sources/env"
 )
 
-func (r *Reader) readFirewall() (firewall settings.Firewall, err error) {
-	vpnInputPortStrings := envToCSV("FIREWALL_VPN_INPUT_PORTS")
-	firewall.VPNInputPorts, err = stringsToPorts(vpnInputPortStrings)
+func (s *Source) readFirewall() (firewall settings.Firewall, err error) {
+	firewall.VPNInputPorts, err = s.env.CSVUint16("FIREWALL_VPN_INPUT_PORTS")
 	if err != nil {
-		return firewall, fmt.Errorf("environment variable FIREWALL_VPN_INPUT_PORTS: %w", err)
+		return firewall, err
 	}
 
-	inputPortStrings := envToCSV("FIREWALL_INPUT_PORTS")
-	firewall.InputPorts, err = stringsToPorts(inputPortStrings)
+	firewall.InputPorts, err = s.env.CSVUint16("FIREWALL_INPUT_PORTS")
 	if err != nil {
-		return firewall, fmt.Errorf("environment variable FIREWALL_INPUT_PORTS: %w", err)
+		return firewall, err
 	}
 
-	outboundSubnetsKey, _ := r.getEnvWithRetro("FIREWALL_OUTBOUND_SUBNETS", "EXTRA_SUBNETS")
-	outboundSubnetStrings := envToCSV(outboundSubnetsKey)
-	firewall.OutboundSubnets, err = stringsToIPNets(outboundSubnetStrings)
+	firewall.OutboundSubnets, err = s.env.CSVNetipPrefixes("FIREWALL_OUTBOUND_SUBNETS",
+		env.RetroKeys("EXTRA_SUBNETS"))
 	if err != nil {
-		return firewall, fmt.Errorf("environment variable %s: %w", outboundSubnetsKey, err)
+		return firewall, err
 	}
 
-	firewall.Enabled, err = envToBoolPtr("FIREWALL")
+	firewall.Enabled, err = s.env.BoolPtr("FIREWALL")
 	if err != nil {
-		return firewall, fmt.Errorf("environment variable FIREWALL: %w", err)
+		return firewall, err
 	}
 
-	firewall.Debug, err = envToBoolPtr("FIREWALL_DEBUG")
+	firewall.Debug, err = s.env.BoolPtr("FIREWALL_DEBUG")
 	if err != nil {
-		return firewall, fmt.Errorf("environment variable FIREWALL_DEBUG: %w", err)
+		return firewall, err
 	}
 
 	return firewall, nil
 }
-
-var (
-	ErrPortParsing = errors.New("cannot parse port")
-	ErrPortValue   = errors.New("port value is not valid")
-)
-
-func stringsToPorts(ss []string) (ports []uint16, err error) {
-	if len(ss) == 0 {
-		return nil, nil
-	}
-	ports = make([]uint16, len(ss))
-	for i, s := range ss {
-		port, err := strconv.Atoi(s)
-		if err != nil {
-			return nil, fmt.Errorf("%w: %s: %s", ErrPortParsing, s, err)
-		} else if port < 1 || port > 65535 {
-			return nil, fmt.Errorf("%w: must be between 1 and 65535: %d",
-				ErrPortValue, port)
-		}
-		ports[i] = uint16(port)
-	}
-	return ports, nil
-}
-
-func stringsToIPNets(ss []string) (ipNets []net.IPNet, err error) {
-	if len(ss) == 0 {
-		return nil, nil
-	}
-	ipNets = make([]net.IPNet, len(ss))
-	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)
-		}
-		ipNet.IP = ip
-		ipNets[i] = *ipNet
-	}
-	return ipNets, nil
-}

internal/configuration/sources/env/health.go

@@ -1,44 +1,35 @@
 package env
 
 import (
-	"fmt"
-	"time"
-
 	"github.com/qdm12/gluetun/internal/configuration/settings"
+	"github.com/qdm12/gosettings/sources/env"
 )
 
-func (r *Reader) ReadHealth() (health settings.Health, err error) {
-	health.ServerAddress = getCleanedEnv("HEALTH_SERVER_ADDRESS")
-	_, health.TargetAddress = r.getEnvWithRetro("HEALTH_TARGET_ADDRESS", "HEALTH_ADDRESS_TO_PING")
+func (s *Source) ReadHealth() (health settings.Health, err error) {
+	health.ServerAddress = s.env.String("HEALTH_SERVER_ADDRESS")
+	health.TargetAddress = s.env.String("HEALTH_TARGET_ADDRESS",
+		env.RetroKeys("HEALTH_ADDRESS_TO_PING"))
 
-	health.VPN.Initial, err = r.readDurationWithRetro(
+	successWaitPtr, err := s.env.DurationPtr("HEALTH_SUCCESS_WAIT_DURATION")
+	if err != nil {
+		return health, err
+	} else if successWaitPtr != nil {
+		health.SuccessWait = *successWaitPtr
+	}
+
+	health.VPN.Initial, err = s.env.DurationPtr(
 		"HEALTH_VPN_DURATION_INITIAL",
-		"HEALTH_OPENVPN_DURATION_INITIAL")
+		env.RetroKeys("HEALTH_OPENVPN_DURATION_INITIAL"))
 	if err != nil {
 		return health, err
 	}
 
-	health.VPN.Addition, err = r.readDurationWithRetro(
+	health.VPN.Addition, err = s.env.DurationPtr(
 		"HEALTH_VPN_DURATION_ADDITION",
-		"HEALTH_OPENVPN_DURATION_ADDITION")
+		env.RetroKeys("HEALTH_OPENVPN_DURATION_ADDITION"))
 	if err != nil {
 		return health, err
 	}
 
 	return health, nil
 }
-
-func (r *Reader) readDurationWithRetro(envKey, retroEnvKey string) (d *time.Duration, err error) {
-	envKey, s := r.getEnvWithRetro(envKey, retroEnvKey)
-	if s == "" {
-		return nil, nil //nolint:nilnil
-	}
-
-	d = new(time.Duration)
-	*d, err = time.ParseDuration(s)
-	if err != nil {
-		return nil, fmt.Errorf("environment variable %s: %w", envKey, err)
-	}
-
-	return d, nil
-}

internal/configuration/sources/env/helpers.go

@@ -3,146 +3,31 @@ package env
 import (
 	"fmt"
 	"os"
-	"strconv"
-	"strings"
-	"time"
 
-	"github.com/qdm12/govalid/binary"
-	"github.com/qdm12/govalid/integer"
+	"github.com/qdm12/gosettings/sources/env"
 )
 
-// getCleanedEnv returns an environment variable value with
-// surrounding spaces and trailing new line characters removed.
-func getCleanedEnv(envKey string) (value string) {
-	value = os.Getenv(envKey)
-	value = strings.TrimSpace(value)
-	value = strings.TrimSuffix(value, "\r\n")
-	value = strings.TrimSuffix(value, "\n")
-	return value
-}
-
-func envToCSV(envKey string) (values []string) {
-	csv := getCleanedEnv(envKey)
-	if csv == "" {
-		return nil
-	}
-	return lowerAndSplit(csv)
-}
-
-func envToInt(envKey string) (n int, err error) {
-	s := getCleanedEnv(envKey)
-	if s == "" {
-		return 0, nil
-	}
-	return strconv.Atoi(s)
-}
-
-func envToFloat64(envKey string) (f float64, err error) {
-	s := getCleanedEnv(envKey)
-	if s == "" {
-		return 0, nil
-	}
-	const bits = 64
-	return strconv.ParseFloat(s, bits)
-}
-
-func envToStringPtr(envKey string) (stringPtr *string) {
-	s := getCleanedEnv(envKey)
-	if s == "" {
-		return nil
-	}
-	return &s
-}
-
-func envToBoolPtr(envKey string) (boolPtr *bool, err error) {
-	s := getCleanedEnv(envKey)
-	if s == "" {
-		return nil, nil //nolint:nilnil
-	}
-	value, err := binary.Validate(s)
-	if err != nil {
-		return nil, err
-	}
-	return &value, nil
-}
-
-func envToIntPtr(envKey string) (intPtr *int, err error) {
-	s := getCleanedEnv(envKey)
-	if s == "" {
-		return nil, nil //nolint:nilnil
-	}
-	value, err := strconv.Atoi(s)
-	if err != nil {
-		return nil, err
-	}
-	return &value, nil
-}
-
-func envToUint8Ptr(envKey string) (uint8Ptr *uint8, err error) {
-	s := getCleanedEnv(envKey)
-	if s == "" {
-		return nil, nil //nolint:nilnil
-	}
-
-	const min, max = 0, 255
-	value, err := integer.Validate(s, integer.OptionRange(min, max))
-	if err != nil {
-		return nil, err
-	}
-
-	uint8Ptr = new(uint8)
-	*uint8Ptr = uint8(value)
-	return uint8Ptr, nil
-}
-
-func envToUint16Ptr(envKey string) (uint16Ptr *uint16, err error) {
-	s := getCleanedEnv(envKey)
-	if s == "" {
-		return nil, nil //nolint:nilnil
-	}
-
-	const min, max = 0, 65535
-	value, err := integer.Validate(s, integer.OptionRange(min, max))
-	if err != nil {
-		return nil, err
-	}
-
-	uint16Ptr = new(uint16)
-	*uint16Ptr = uint16(value)
-	return uint16Ptr, nil
-}
-
-func envToDurationPtr(envKey string) (durationPtr *time.Duration, err error) {
-	s := getCleanedEnv(envKey)
-	if s == "" {
-		return nil, nil //nolint:nilnil
-	}
-
-	durationPtr = new(time.Duration)
-	*durationPtr, err = time.ParseDuration(s)
-	if err != nil {
-		return nil, err
-	}
-
-	return durationPtr, nil
-}
-
-func lowerAndSplit(csv string) (values []string) {
-	csv = strings.ToLower(csv)
-	return strings.Split(csv, ",")
-}
-
 func unsetEnvKeys(envKeys []string, err error) (newErr error) {
 	newErr = err
 	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
 }
 
-func stringPtr(s string) *string { return &s }
-func uint32Ptr(n uint32) *uint32 { return &n }
-func boolPtr(b bool) *bool       { return &b }
+func ptrTo[T any](value T) *T {
+	return &value
+}
+
+func firstKeySet(e env.Env, keys ...string) (firstKeySet string) {
+	for _, key := range keys {
+		value := e.Get(key)
+		if value != nil {
+			return key
+		}
+	}
+	return ""
+}

internal/configuration/sources/env/helpers_test.go

@@ -1,22 +0,0 @@
-package env
-
-import (
-	"os"
-	"testing"
-
-	"github.com/stretchr/testify/assert"
-	"github.com/stretchr/testify/require"
-)
-
-// setTestEnv is used to set environment variables in
-// parallel tests.
-func setTestEnv(t *testing.T, key, value string) {
-	t.Helper()
-	existing := os.Getenv(key)
-	err := os.Setenv(key, value) //nolint:tenv
-	t.Cleanup(func() {
-		err = os.Setenv(key, existing)
-		assert.NoError(t, err)
-	})
-	require.NoError(t, err)
-}

internal/configuration/sources/env/httproxy.go

@@ -4,25 +4,35 @@ import (
 	"fmt"
 
 	"github.com/qdm12/gluetun/internal/configuration/settings"
+	"github.com/qdm12/gosettings/sources/env"
 	"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.env.Get("HTTPPROXY_USER",
+		env.RetroKeys("PROXY_USER", "TINYPROXY_USER"),
+		env.ForceLowercase(false))
 
-	httpProxy.Enabled, err = r.readHTTProxyEnabled()
+	httpProxy.Password = s.env.Get("HTTPPROXY_PASSWORD",
+		env.RetroKeys("PROXY_PASSWORD", "TINYPROXY_PASSWORD"),
+		env.ForceLowercase(false))
+
+	httpProxy.ListeningAddress, err = s.readHTTProxyListeningAddress()
 	if err != nil {
 		return httpProxy, err
 	}
 
-	httpProxy.Stealth, err = envToBoolPtr("HTTPPROXY_STEALTH")
+	httpProxy.Enabled, err = s.env.BoolPtr("HTTPPROXY", env.RetroKeys("PROXY", "TINYPROXY"))
 	if err != nil {
-		return httpProxy, fmt.Errorf("environment variable HTTPPROXY_STEALTH: %w", err)
+		return httpProxy, err
 	}
 
-	httpProxy.Log, err = r.readHTTProxyLog()
+	httpProxy.Stealth, err = s.env.BoolPtr("HTTPPROXY_STEALTH")
+	if err != nil {
+		return httpProxy, err
+	}
+
+	httpProxy.Log, err = s.readHTTProxyLog()
 	if err != nil {
 		return httpProxy, err
 	}
@@ -30,59 +40,42 @@ 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) readHTTProxyListeningAddress() (listeningAddress string, err error) {
+	const currentKey = "HTTPPROXY_LISTENING_ADDRESS"
+	key := firstKeySet(s.env, "HTTPPROXY_PORT", "TINYPROXY_PORT", "PROXY_PORT",
+		currentKey)
+	switch key {
+	case "":
+		return "", nil
+	case currentKey:
+		return s.env.String(key), nil
 	}
-	return nil
+
+	// Retro-compatible keys using a port only
+	s.handleDeprecatedKey(key, currentKey)
+	port, err := s.env.Uint16Ptr(key)
+	if err != nil {
+		return "", err
+	}
+	return fmt.Sprintf(":%d", *port), nil
 }
 
-func (r *Reader) readHTTProxyPassword() (user *string) {
-	_, s := r.getEnvWithRetro("HTTPPROXY_PASSWORD", "PROXY_PASSWORD", "TINYPROXY_PASSWORD")
-	if s != "" {
-		return &s
-	}
-	return nil
-}
-
-func (r *Reader) readHTTProxyListeningAddress() (listeningAddress string) {
-	key, value := r.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) readHTTProxyLog() (enabled *bool, err error) {
+	const currentKey = "HTTPPROXY_LOG"
+	key := firstKeySet(s.env, "PROXY_LOG", "TINYPROXY_LOG", "HTTPPROXY_LOG")
+	switch key {
+	case "":
 		return nil, nil //nolint:nilnil
+	case currentKey:
+		return s.env.BoolPtr(key)
 	}
 
-	enabled = new(bool)
-	*enabled, err = binary.Validate(s)
-	if err != nil {
-		return nil, fmt.Errorf("environment variable %s: %w", key, err)
-	}
-
-	return enabled, nil
-}
-
-func (r *Reader) readHTTProxyLog() (enabled *bool, err error) {
-	key, s := r.getEnvWithRetro("HTTPPROXY_LOG", "PROXY_LOG_LEVEL", "TINYPROXY_LOG")
-	if s == "" {
-		return nil, nil //nolint:nilnil
-	}
-
-	var binaryOptions []binary.Option
-	if key != "HTTPROXY_LOG" {
-		retroOption := binary.OptionEnabled("on", "info", "connect", "notice")
-		binaryOptions = append(binaryOptions, retroOption)
-	}
-
-	enabled = new(bool)
-	*enabled, err = binary.Validate(s, binaryOptions...)
+	// Retro-compatible keys using different boolean verbs
+	s.handleDeprecatedKey(key, currentKey)
+	value := s.env.String(key)
+	retroOption := binary.OptionEnabled("on", "info", "connect", "notice")
+
+	enabled, err = binary.Validate(value, retroOption)
 	if err != nil {
 		return nil, fmt.Errorf("environment variable %s: %w", key, err)
 	}

internal/configuration/sources/env/log.go

@@ -9,8 +9,8 @@ import (
 	"github.com/qdm12/log"
 )
 
-func readLog() (log settings.Log, err error) {
-	log.Level, err = readLogLevel()
+func (s *Source) readLog() (log settings.Log, err error) {
+	log.Level, err = s.readLogLevel()
 	if err != nil {
 		return log, err
 	}
@@ -18,14 +18,14 @@ func readLog() (log settings.Log, err error) {
 	return log, nil
 }
 
-func readLogLevel() (level *log.Level, err error) {
-	s := getCleanedEnv("LOG_LEVEL")
-	if s == "" {
+func (s *Source) readLogLevel() (level *log.Level, err error) {
+	value := s.env.String("LOG_LEVEL")
+	if value == "" {
 		return nil, nil //nolint:nilnil
 	}
 
 	level = new(log.Level)
-	*level, err = parseLogLevel(s)
+	*level, err = parseLogLevel(value)
 	if err != nil {
 		return nil, fmt.Errorf("environment variable LOG_LEVEL: %w", err)
 	}

internal/configuration/sources/env/openvpn.go

@@ -1,108 +1,77 @@
 package env
 
 import (
-	"fmt"
 	"strings"
 
 	"github.com/qdm12/gluetun/internal/configuration/settings"
-	"github.com/qdm12/govalid/binary"
+	"github.com/qdm12/gosettings/sources/env"
 )
 
-func (r *Reader) readOpenVPN() (
+func (s *Source) readOpenVPN() (
 	openVPN settings.OpenVPN, err error) {
 	defer func() {
-		err = unsetEnvKeys([]string{"OPENVPN_CLIENTKEY", "OPENVPN_CLIENTCRT"}, err)
+		err = unsetEnvKeys([]string{"OPENVPN_KEY", "OPENVPN_CERT",
+			"OPENVPN_KEY_PASSPHRASE", "OPENVPN_ENCRYPTED_KEY"}, err)
 	}()
 
-	openVPN.Version = getCleanedEnv("OPENVPN_VERSION")
-	openVPN.User = r.readOpenVPNUser()
-	openVPN.Password = r.readOpenVPNPassword()
-	confFile := getCleanedEnv("OPENVPN_CUSTOM_CONFIG")
-	if confFile != "" {
-		openVPN.ConfFile = &confFile
-	}
+	openVPN.Version = s.env.String("OPENVPN_VERSION")
+	openVPN.User = s.env.Get("OPENVPN_USER",
+		env.RetroKeys("USER"), env.ForceLowercase(false))
+	openVPN.Password = s.env.Get("OPENVPN_PASSWORD",
+		env.RetroKeys("PASSWORD"), env.ForceLowercase(false))
+	openVPN.ConfFile = s.env.Get("OPENVPN_CUSTOM_CONFIG", env.ForceLowercase(false))
+	openVPN.Ciphers = s.env.CSV("OPENVPN_CIPHERS", env.RetroKeys("OPENVPN_CIPHER"))
+	openVPN.Auth = s.env.Get("OPENVPN_AUTH")
+	openVPN.Cert = s.env.Get("OPENVPN_CERT", env.ForceLowercase(false))
+	openVPN.Key = s.env.Get("OPENVPN_KEY", env.ForceLowercase(false))
+	openVPN.EncryptedKey = s.env.Get("OPENVPN_ENCRYPTED_KEY", env.ForceLowercase(false))
+	openVPN.KeyPassphrase = s.env.Get("OPENVPN_KEY_PASSPHRASE", env.ForceLowercase(false))
 
-	ciphersKey, _ := r.getEnvWithRetro("OPENVPN_CIPHERS", "OPENVPN_CIPHER")
-	openVPN.Ciphers = envToCSV(ciphersKey)
+	openVPN.PIAEncPreset = s.readPIAEncryptionPreset()
 
-	auth := getCleanedEnv("OPENVPN_AUTH")
-	if auth != "" {
-		openVPN.Auth = &auth
-	}
-
-	openVPN.ClientCrt = envToStringPtr("OPENVPN_CLIENTCRT")
-	openVPN.ClientKey = envToStringPtr("OPENVPN_CLIENTKEY")
-
-	openVPN.PIAEncPreset = r.readPIAEncryptionPreset()
-
-	openVPN.IPv6, err = envToBoolPtr("OPENVPN_IPV6")
-	if err != nil {
-		return openVPN, fmt.Errorf("environment variable OPENVPN_IPV6: %w", err)
-	}
-
-	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.ProcessUser, err = r.readOpenVPNProcessUser()
+	openVPN.MSSFix, err = s.env.Uint16Ptr("OPENVPN_MSSFIX")
 	if err != nil {
 		return openVPN, err
 	}
 
-	openVPN.Verbosity, err = envToIntPtr("OPENVPN_VERBOSITY")
+	openVPN.Interface = s.env.String("VPN_INTERFACE",
+		env.RetroKeys("OPENVPN_INTERFACE"), env.ForceLowercase(false))
+
+	openVPN.ProcessUser, err = s.readOpenVPNProcessUser()
 	if err != nil {
-		return openVPN, fmt.Errorf("environment variable OPENVPN_VERBOSITY: %w", err)
+		return openVPN, err
 	}
 
-	flagsStr := getCleanedEnv("OPENVPN_FLAGS")
-	if flagsStr != "" {
-		openVPN.Flags = strings.Fields(flagsStr)
+	openVPN.Verbosity, err = s.env.IntPtr("OPENVPN_VERBOSITY")
+	if err != nil {
+		return openVPN, err
+	}
+
+	flagsPtr := s.env.Get("OPENVPN_FLAGS", env.ForceLowercase(false))
+	if flagsPtr != nil {
+		openVPN.Flags = strings.Fields(*flagsPtr)
 	}
 
 	return openVPN, nil
 }
 
-func (r *Reader) readOpenVPNUser() (user string) {
-	_, user = r.getEnvWithRetro("OPENVPN_USER", "USER")
-	// Remove spaces in user ID to simplify user's life, thanks @JeordyR
-	return strings.ReplaceAll(user, " ", "")
-}
-
-func (r *Reader) readOpenVPNPassword() (password string) {
-	_, password = r.getEnvWithRetro("OPENVPN_PASSWORD", "PASSWORD")
-	return password
-}
-
-func (r *Reader) readPIAEncryptionPreset() (presetPtr *string) {
-	_, preset := r.getEnvWithRetro(
+func (s *Source) readPIAEncryptionPreset() (presetPtr *string) {
+	return s.env.Get(
 		"PRIVATE_INTERNET_ACCESS_OPENVPN_ENCRYPTION_PRESET",
-		"PIA_ENCRYPTION", "ENCRYPTION")
-	if preset != "" {
-		return &preset
-	}
-	return nil
+		env.RetroKeys("ENCRYPTION", "PIA_ENCRYPTION"))
 }
 
-func (r *Reader) readOpenVPNProcessUser() (processUser string, err error) {
-	key, value := r.getEnvWithRetro("OPENVPN_PROCESS_USER", "OPENVPN_ROOT")
-	if key == "OPENVPN_PROCESS_USER" {
-		return value, nil
-	}
-
-	// Retro-compatibility
-	if value == "" {
-		return "", nil
-	}
-	root, err := binary.Validate(value)
+func (s *Source) readOpenVPNProcessUser() (processUser string, err error) {
+	value, err := s.env.BoolPtr("OPENVPN_ROOT") // Retro-compatibility
 	if err != nil {
-		return "", fmt.Errorf("environment variable %s: %w", key, err)
+		return "", err
+	} else if value != nil {
+		if *value {
+			return "root", nil
+		}
+		const defaultNonRootUser = "nonrootuser"
+		return defaultNonRootUser, nil
 	}
-	if root {
-		return "root", nil
-	}
-	const defaultNonRootUser = "nonrootuser"
-	return defaultNonRootUser, nil
+
+	return s.env.String("OPENVPN_PROCESS_USER"), nil
 }

internal/configuration/sources/env/openvpnselection.go

@@ -7,60 +7,50 @@ import (
 
 	"github.com/qdm12/gluetun/internal/configuration/settings"
 	"github.com/qdm12/gluetun/internal/constants"
-	"github.com/qdm12/govalid/port"
+	"github.com/qdm12/gosettings/sources/env"
 )
 
-func (r *Reader) readOpenVPNSelection() (
+func (s *Source) readOpenVPNSelection() (
 	selection settings.OpenVPNSelection, err error) {
-	confFile := getCleanedEnv("OPENVPN_CUSTOM_CONFIG")
-	if confFile != "" {
-		selection.ConfFile = &confFile
-	}
+	selection.ConfFile = s.env.Get("OPENVPN_CUSTOM_CONFIG", env.ForceLowercase(false))
 
-	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.env.Uint16Ptr("VPN_ENDPOINT_PORT",
+		env.RetroKeys("PORT", "OPENVPN_PORT"))
 	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")
-
-	switch strings.ToLower(protocol) {
+func (s *Source) readOpenVPNProtocol() (tcp *bool, err error) {
+	const currentKey = "OPENVPN_PROTOCOL"
+	envKey := firstKeySet(s.env, "PROTOCOL", currentKey)
+	switch envKey {
 	case "":
 		return nil, nil //nolint:nilnil
+	case currentKey:
+	default: // Retro compatibility
+		s.handleDeprecatedKey(envKey, currentKey)
+	}
+
+	protocol := s.env.String(envKey)
+	switch strings.ToLower(protocol) {
 	case constants.UDP:
-		return boolPtr(false), nil
+		return ptrTo(false), nil
 	case constants.TCP:
-		return boolPtr(true), nil
+		return ptrTo(true), nil
 	default:
 		return nil, fmt.Errorf("environment variable %s: %w: %s",
 			envKey, ErrOpenVPNProtocolNotValid, protocol)
 	}
 }
-
-func (r *Reader) readOpenVPNCustomPort() (customPort *uint16, err error) {
-	key, s := r.getEnvWithRetro("VPN_ENDPOINT_PORT", "PORT", "OPENVPN_PORT")
-	if s == "" {
-		return nil, nil //nolint:nilnil
-	}
-
-	customPort = new(uint16)
-	*customPort, err = port.Validate(s)
-	if err != nil {
-		return nil, fmt.Errorf("environment variable %s: %w", key, err)
-	}
-
-	return customPort, nil
-}

internal/configuration/sources/env/portforward.go

@@ -1,26 +1,33 @@
 package env
 
 import (
-	"fmt"
-
 	"github.com/qdm12/gluetun/internal/configuration/settings"
+	"github.com/qdm12/gosettings/sources/env"
 )
 
-func (r *Reader) readPortForward() (
+func (s *Source) readPortForward() (
 	portForwarding settings.PortForwarding, err error) {
-	key, _ := r.getEnvWithRetro(
-		"PRIVATE_INTERNET_ACCESS_VPN_PORT_FORWARDING",
-		"PORT_FORWARDING")
-	portForwarding.Enabled, err = envToBoolPtr(key)
+	portForwarding.Enabled, err = s.env.BoolPtr("VPN_PORT_FORWARDING",
+		env.RetroKeys(
+			"PORT_FORWARDING",
+			"PRIVATE_INTERNET_ACCESS_VPN_PORT_FORWARDING",
+		))
 	if err != nil {
-		return portForwarding, fmt.Errorf("environment variable %s: %w", key, err)
+		return portForwarding, err
 	}
 
-	_, value := r.getEnvWithRetro(
-		"PRIVATE_INTERNET_ACCESS_VPN_PORT_FORWARDING_STATUS_FILE",
-		"PORT_FORWARDING_STATUS_FILE")
-	if value != "" {
-		portForwarding.Filepath = stringPtr(value)
+	portForwarding.Provider = s.env.Get("VPN_PORT_FORWARDING_PROVIDER")
+
+	portForwarding.Filepath = s.env.Get("VPN_PORT_FORWARDING_STATUS_FILE",
+		env.ForceLowercase(false),
+		env.RetroKeys(
+			"PORT_FORWARDING_STATUS_FILE",
+			"PRIVATE_INTERNET_ACCESS_VPN_PORT_FORWARDING_STATUS_FILE",
+		))
+
+	portForwarding.ListeningPort, err = s.env.Uint16Ptr("VPN_PORT_FORWARDING_LISTENING_PORT")
+	if err != nil {
+		return portForwarding, err
 	}
 
 	return portForwarding, nil

internal/configuration/sources/env/pprof.go

@@ -1,28 +1,26 @@
 package env
 
 import (
-	"fmt"
-
 	"github.com/qdm12/gluetun/internal/pprof"
 )
 
-func readPprof() (settings pprof.Settings, err error) {
-	settings.Enabled, err = envToBoolPtr("PPROF_ENABLED")
+func (s *Source) readPprof() (settings pprof.Settings, err error) {
+	settings.Enabled, err = s.env.BoolPtr("PPROF_ENABLED")
 	if err != nil {
-		return settings, fmt.Errorf("environment variable PPROF_ENABLED: %w", err)
+		return settings, err
 	}
 
-	settings.BlockProfileRate, err = envToInt("PPROF_BLOCK_PROFILE_RATE")
+	settings.BlockProfileRate, err = s.env.IntPtr("PPROF_BLOCK_PROFILE_RATE")
 	if err != nil {
-		return settings, fmt.Errorf("environment variable PPROF_BLOCK_PROFILE_RATE: %w", err)
+		return settings, err
 	}
 
-	settings.MutexProfileRate, err = envToInt("PPROF_MUTEX_PROFILE_RATE")
+	settings.MutexProfileRate, err = s.env.IntPtr("PPROF_MUTEX_PROFILE_RATE")
 	if err != nil {
-		return settings, fmt.Errorf("environment variable PPROF_MUTEX_PROFILE_RATE: %w", err)
+		return settings, err
 	}
 
-	settings.HTTPServer.Address = getCleanedEnv("PPROF_HTTP_SERVER_ADDRESS")
+	settings.HTTPServer.Address = s.env.String("PPROF_HTTP_SERVER_ADDRESS")
 
 	return settings, nil
 }

internal/configuration/sources/env/provider.go

@@ -7,21 +7,22 @@ import (
 	"github.com/qdm12/gluetun/internal/configuration/settings"
 	"github.com/qdm12/gluetun/internal/constants/providers"
 	"github.com/qdm12/gluetun/internal/constants/vpn"
+	"github.com/qdm12/gosettings/sources/env"
 )
 
-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 +30,21 @@ 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) {
+	valuePtr := s.env.Get("VPN_SERVICE_PROVIDER", env.RetroKeys("VPNSP"))
+	if valuePtr == nil {
+		if vpnType != vpn.Wireguard && s.env.Get("OPENVPN_CUSTOM_CONFIG") != nil {
+			// retro compatibility
+			return ptrTo(providers.Custom)
+		}
 		return nil
-	case s == "pia": // retro compatibility
-		return stringPtr(providers.PrivateInternetAccess)
 	}
-	return stringPtr(s)
+
+	value := *valuePtr
+	value = strings.ToLower(value)
+	if value == "pia" { // retro compatibility
+		return ptrTo(providers.PrivateInternetAccess)
+	}
+
+	return ptrTo(value)
 }

internal/configuration/sources/env/publicip.go

@@ -1,42 +1,22 @@
 package env
 
 import (
-	"fmt"
-	"time"
-
 	"github.com/qdm12/gluetun/internal/configuration/settings"
+	"github.com/qdm12/gosettings/sources/env"
 )
 
-func (r *Reader) readPublicIP() (publicIP settings.PublicIP, err error) {
-	publicIP.Period, err = readPublicIPPeriod()
+func (s *Source) readPublicIP() (publicIP settings.PublicIP, err error) {
+	publicIP.Period, err = s.env.DurationPtr("PUBLICIP_PERIOD")
 	if err != nil {
 		return publicIP, err
 	}
 
-	publicIP.IPFilepath = r.readPublicIPFilepath()
+	publicIP.IPFilepath = s.env.Get("PUBLICIP_FILE",
+		env.ForceLowercase(false), env.RetroKeys("IP_STATUS_FILE"))
+
+	publicIP.API = s.env.String("PUBLICIP_API")
+
+	publicIP.APIToken = s.env.Get("PUBLICIP_API_TOKEN")
 
 	return publicIP, nil
 }
-
-func readPublicIPPeriod() (period *time.Duration, err error) {
-	s := getCleanedEnv("PUBLICIP_PERIOD")
-	if s == "" {
-		return nil, nil //nolint:nilnil
-	}
-
-	period = new(time.Duration)
-	*period, err = time.ParseDuration(s)
-	if err != nil {
-		return nil, fmt.Errorf("environment variable PUBLICIP_PERIOD: %w", err)
-	}
-
-	return period, nil
-}
-
-func (r *Reader) readPublicIPFilepath() (filepath *string) {
-	_, s := r.getEnvWithRetro("PUBLICIP_FILE", "IP_STATUS_FILE")
-	if s != "" {
-		return &s
-	}
-	return nil
-}

internal/configuration/sources/env/reader.go

@@ -1,120 +1,103 @@
 package env
 
 import (
+	"os"
+
 	"github.com/qdm12/gluetun/internal/configuration/settings"
-	"github.com/qdm12/gluetun/internal/configuration/sources"
+	"github.com/qdm12/gosettings/sources/env"
 )
 
-var _ sources.Source = (*Reader)(nil)
-
-type Reader struct {
-	warner Warner
+type Source struct {
+	env                 env.Env
+	warner              Warner
+	handleDeprecatedKey func(deprecatedKey, newKey string)
 }
 
 type Warner interface {
 	Warn(s string)
 }
 
-func New(warner Warner) *Reader {
-	return &Reader{
-		warner: warner,
+func New(warner Warner) *Source {
+	handleDeprecatedKey := func(deprecatedKey, newKey string) {
+		warner.Warn(
+			"You are using the old environment variable " + deprecatedKey +
+				", please consider changing it to " + newKey)
+	}
+
+	return &Source{
+		env:                 *env.New(os.Environ(), handleDeprecatedKey),
+		warner:              warner,
+		handleDeprecatedKey: handleDeprecatedKey,
 	}
 }
 
-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
 	}
 
-	settings.Log, err = readLog()
+	settings.Log, err = s.readLog()
 	if err != nil {
 		return settings, err
 	}
 
-	settings.PublicIP, err = r.readPublicIP()
+	settings.PublicIP, err = s.readPublicIP()
 	if err != nil {
 		return settings, err
 	}
 
-	settings.Updater, err = readUpdater()
+	settings.Updater, err = s.readUpdater()
 	if err != nil {
 		return settings, err
 	}
 
-	settings.Version, err = readVersion()
+	settings.Version, err = s.readVersion()
 	if err != nil {
 		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
 	}
 
-	settings.Pprof, err = readPprof()
+	settings.Pprof, err = s.readPprof()
 	if err != nil {
 		return settings, err
 	}
 
 	return settings, nil
 }
-
-func (r *Reader) onRetroActive(oldKey, newKey string) {
-	r.warner.Warn(
-		"You are using the old environment variable " + oldKey +
-			", please consider changing it to " + newKey)
-}
-
-// getEnvWithRetro returns the first environment variable
-// key and corresponding non empty value from the environment
-// variable keys given. It first goes through the retroKeys
-// 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,
-	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)
-			return key, value
-		}
-	}
-
-	return currentKey, getCleanedEnv(currentKey)
-}

internal/configuration/sources/env/server.go

@@ -1,48 +1,31 @@
 package env
 
 import (
-	"fmt"
-
 	"github.com/qdm12/gluetun/internal/configuration/settings"
-	"github.com/qdm12/govalid/binary"
 )
 
-func (r *Reader) readControlServer() (controlServer settings.ControlServer, err error) {
-	controlServer.Log, err = readControlServerLog()
+func (s *Source) readControlServer() (controlServer settings.ControlServer, err error) {
+	controlServer.Log, err = s.env.BoolPtr("HTTP_CONTROL_SERVER_LOG")
 	if err != nil {
 		return controlServer, err
 	}
 
-	controlServer.Address = r.readControlServerAddress()
+	controlServer.Address = s.readControlServerAddress()
 
 	return controlServer, nil
 }
 
-func readControlServerLog() (enabled *bool, err error) {
-	s := getCleanedEnv("HTTP_CONTROL_SERVER_LOG")
-	if s == "" {
-		return nil, nil //nolint:nilnil
+func (s *Source) readControlServerAddress() (address *string) {
+	const currentKey = "HTTP_CONTROL_SERVER_ADDRESS"
+	key := firstKeySet(s.env, "CONTROL_SERVER_ADDRESS", currentKey)
+	if key == currentKey {
+		return s.env.Get(key)
 	}
 
-	log, err := binary.Validate(s)
-	if err != nil {
-		return nil, fmt.Errorf("environment variable HTTP_CONTROL_SERVER_LOG: %w", err)
-	}
-
-	return &log, nil
-}
-
-func (r *Reader) readControlServerAddress() (address *string) {
-	key, s := r.getEnvWithRetro("HTTP_CONTROL_SERVER_ADDRESS", "HTTP_CONTROL_SERVER_PORT")
-	if s == "" {
+	s.handleDeprecatedKey(key, currentKey)
+	value := s.env.Get("CONTROL_SERVER_ADDRESS")
+	if value == nil {
 		return nil
 	}
-
-	if key == "HTTP_CONTROL_SERVER_ADDRESS" {
-		return &s
-	}
-
-	address = new(string)
-	*address = ":" + s
-	return address
+	return ptrTo(":" + *value)
 }

internal/configuration/sources/env/serverselection.go

@@ -2,99 +2,84 @@ package env
 
 import (
 	"errors"
-	"fmt"
-	"net"
-	"strconv"
-	"strings"
 
 	"github.com/qdm12/gluetun/internal/configuration/settings"
 	"github.com/qdm12/gluetun/internal/constants/providers"
+	"github.com/qdm12/gosettings/sources/env"
 )
 
-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.env.NetipAddr("VPN_ENDPOINT_IP",
+		env.RetroKeys("OPENVPN_TARGET_IP"))
 	if err != nil {
 		return ss, err
 	}
 
-	countriesKey, _ := r.getEnvWithRetro("SERVER_COUNTRIES", "COUNTRY")
-	ss.Countries = envToCSV(countriesKey)
+	ss.Countries = s.env.CSV("SERVER_COUNTRIES", env.RetroKeys("COUNTRY"))
 	if vpnProvider == providers.Cyberghost && len(ss.Countries) == 0 {
 		// Retro-compatibility for Cyberghost using the REGION variable
-		ss.Countries = envToCSV("REGION")
+		ss.Countries = s.env.CSV("REGION")
 		if len(ss.Countries) > 0 {
-			r.onRetroActive("REGION", "SERVER_COUNTRIES")
+			s.handleDeprecatedKey("REGION", "SERVER_COUNTRIES")
 		}
 	}
 
-	regionsKey, _ := r.getEnvWithRetro("SERVER_REGIONS", "REGION")
-	ss.Regions = envToCSV(regionsKey)
-
-	citiesKey, _ := r.getEnvWithRetro("SERVER_CITIES", "CITY")
-	ss.Cities = envToCSV(citiesKey)
-
-	ss.ISPs = envToCSV("ISP")
-
-	hostnamesKey, _ := r.getEnvWithRetro("SERVER_HOSTNAMES", "SERVER_HOSTNAME")
-	ss.Hostnames = envToCSV(hostnamesKey)
-
-	serverNamesKey, _ := r.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)
-			if err != nil {
-				return ss, fmt.Errorf("%w: %s",
-					ErrServerNumberNotValid, numberString)
-			} else if number < 0 || number > 65535 {
-				return ss, fmt.Errorf("%w: %d must be between 0 and 65535",
-					ErrServerNumberNotValid, number)
-			}
-			numbers[i] = uint16(number)
-		}
-		ss.Numbers = numbers
+	ss.Regions = s.env.CSV("SERVER_REGIONS", env.RetroKeys("REGION"))
+	ss.Cities = s.env.CSV("SERVER_CITIES", env.RetroKeys("CITY"))
+	ss.ISPs = s.env.CSV("ISP")
+	ss.Hostnames = s.env.CSV("SERVER_HOSTNAMES", env.RetroKeys("SERVER_HOSTNAME"))
+	ss.Names = s.env.CSV("SERVER_NAMES", env.RetroKeys("SERVER_NAME"))
+	ss.Numbers, err = s.env.CSVUint16("SERVER_NUMBER")
+	ss.Categories = s.env.CSV("SERVER_CATEGORIES")
+	if err != nil {
+		return ss, err
 	}
 
 	// Mullvad only
-	ss.OwnedOnly, err = r.readOwnedOnly()
+	ss.OwnedOnly, err = s.env.BoolPtr("OWNED_ONLY", env.RetroKeys("OWNED"))
 	if err != nil {
 		return ss, err
 	}
 
 	// VPNUnlimited and ProtonVPN only
-	ss.FreeOnly, err = envToBoolPtr("FREE_ONLY")
-	if err != nil {
-		return ss, fmt.Errorf("environment variable FREE_ONLY: %w", err)
-	}
-
-	// VPNUnlimited only
-	ss.MultiHopOnly, err = envToBoolPtr("MULTIHOP_ONLY")
-	if err != nil {
-		return ss, fmt.Errorf("environment variable MULTIHOP_ONLY: %w", err)
-	}
-
-	// VPNUnlimited only
-	ss.MultiHopOnly, err = envToBoolPtr("STREAM_ONLY")
-	if err != nil {
-		return ss, fmt.Errorf("environment variable STREAM_ONLY: %w", err)
-	}
-
-	ss.OpenVPN, err = r.readOpenVPNSelection()
+	ss.FreeOnly, err = s.env.BoolPtr("FREE_ONLY")
 	if err != nil {
 		return ss, err
 	}
 
-	ss.Wireguard, err = r.readWireguardSelection()
+	// VPNSecure only
+	ss.PremiumOnly, err = s.env.BoolPtr("PREMIUM_ONLY")
+	if err != nil {
+		return ss, err
+	}
+
+	// Surfshark only
+	ss.MultiHopOnly, err = s.env.BoolPtr("MULTIHOP_ONLY")
+	if err != nil {
+		return ss, err
+	}
+
+	// VPNUnlimited only
+	ss.StreamOnly, err = s.env.BoolPtr("STREAM_ONLY")
+	if err != nil {
+		return ss, err
+	}
+
+	// PIA only
+	ss.PortForwardOnly, err = s.env.BoolPtr("PORT_FORWARD_ONLY")
+	if err != nil {
+		return ss, err
+	}
+
+	ss.OpenVPN, err = s.readOpenVPNSelection()
+	if err != nil {
+		return ss, err
+	}
+
+	ss.Wireguard, err = s.readWireguardSelection()
 	if err != nil {
 		return ss, err
 	}
@@ -105,27 +90,3 @@ func (r *Reader) readServerSelection(vpnProvider, vpnType string) (
 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 == "" {
-		return nil, nil
-	}
-
-	ip = net.ParseIP(s)
-	if ip == nil {
-		return nil, fmt.Errorf("environment variable %s: %w: %s",
-			envKey, ErrInvalidIP, s)
-	}
-
-	return ip, nil
-}
-
-func (r *Reader) readOwnedOnly() (ownedOnly *bool, err error) {
-	envKey, _ := r.getEnvWithRetro("OWNED_ONLY", "OWNED")
-	ownedOnly, err = envToBoolPtr(envKey)
-	if err != nil {
-		return nil, fmt.Errorf("environment variable %s: %w", envKey, err)
-	}
-	return ownedOnly, nil
-}

internal/configuration/sources/env/shadowsocks.go

@@ -2,43 +2,41 @@ package env
 
 import (
 	"fmt"
-	"strings"
 
 	"github.com/qdm12/gluetun/internal/configuration/settings"
+	"github.com/qdm12/gosettings/sources/env"
 )
 
-func (r *Reader) readShadowsocks() (shadowsocks settings.Shadowsocks, err error) {
-	shadowsocks.Enabled, err = envToBoolPtr("SHADOWSOCKS")
+func (s *Source) readShadowsocks() (shadowsocks settings.Shadowsocks, err error) {
+	shadowsocks.Enabled, err = s.env.BoolPtr("SHADOWSOCKS")
 	if err != nil {
-		return shadowsocks, fmt.Errorf("environment variable SHADOWSOCKS: %w", err)
+		return shadowsocks, err
 	}
 
-	shadowsocks.Address = r.readShadowsocksAddress()
-	shadowsocks.LogAddresses, err = envToBoolPtr("SHADOWSOCKS_LOG")
+	shadowsocks.Address, err = s.readShadowsocksAddress()
 	if err != nil {
-		return shadowsocks, fmt.Errorf("environment variable SHADOWSOCKS_LOG: %w", err)
+		return shadowsocks, err
 	}
-	shadowsocks.CipherName = r.readShadowsocksCipher()
-	shadowsocks.Password = envToStringPtr("SHADOWSOCKS_PASSWORD")
+	shadowsocks.LogAddresses, err = s.env.BoolPtr("SHADOWSOCKS_LOG")
+	if err != nil {
+		return shadowsocks, err
+	}
+	shadowsocks.CipherName = s.env.String("SHADOWSOCKS_CIPHER",
+		env.RetroKeys("SHADOWSOCKS_METHOD"))
+	shadowsocks.Password = s.env.Get("SHADOWSOCKS_PASSWORD", env.ForceLowercase(false))
 
 	return shadowsocks, nil
 }
 
-func (r *Reader) readShadowsocksAddress() (address string) {
-	key, value := r.getEnvWithRetro("SHADOWSOCKS_LISTENING_ADDRESS", "SHADOWSOCKS_PORT")
-	if value == "" {
-		return ""
+func (s *Source) readShadowsocksAddress() (address *string, err error) {
+	const currentKey = "SHADOWSOCKS_LISTENING_ADDRESS"
+	port, err := s.env.Uint16Ptr("SHADOWSOCKS_PORT") // retro-compatibility
+	if err != nil {
+		return nil, err
+	} else if port != nil {
+		s.handleDeprecatedKey("SHADOWSOCKS_PORT", currentKey)
+		return ptrTo(fmt.Sprintf(":%d", *port)), nil
 	}
 
-	if key == "SHADOWSOCKS_LISTENING_ADDRESS" {
-		return value
-	}
-
-	// Retro-compatibility
-	return ":" + value
-}
-
-func (r *Reader) readShadowsocksCipher() (cipher string) {
-	_, cipher = r.getEnvWithRetro("SHADOWSOCKS_CIPHER", "SHADOWSOCKS_METHOD")
-	return strings.ToLower(cipher)
+	return s.env.Get(currentKey), nil
 }

internal/configuration/sources/env/system.go

@@ -1,55 +1,22 @@
 package env
 
 import (
-	"errors"
-	"fmt"
-	"strconv"
-
 	"github.com/qdm12/gluetun/internal/configuration/settings"
+	"github.com/qdm12/gosettings/sources/env"
 )
 
-var (
-	ErrSystemPUIDNotValid     = errors.New("PUID is not valid")
-	ErrSystemPGIDNotValid     = errors.New("PGID is not valid")
-	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.env.Uint32Ptr("PUID", env.RetroKeys("UID"))
 	if err != nil {
 		return system, err
 	}
 
-	system.PGID, err = r.readID("PGID", "GID")
+	system.PGID, err = s.env.Uint32Ptr("PGID", env.RetroKeys("GID"))
 	if err != nil {
 		return system, err
 	}
 
-	system.Timezone = getCleanedEnv("TZ")
+	system.Timezone = s.env.String("TZ")
 
 	return system, nil
 }
-
-var ErrSystemIDNotValid = errors.New("system ID is not valid")
-
-func (r *Reader) readID(key, retroKey string) (
-	id *uint32, err error) {
-	idEnvKey, idString := r.getEnvWithRetro(key, retroKey)
-	if idString == "" {
-		return nil, nil //nolint:nilnil
-	}
-
-	const base = 10
-	const bitSize = 64
-	const max = uint64(^uint32(0))
-	idUint64, err := strconv.ParseUint(idString, base, bitSize)
-	if err != nil {
-		return nil, fmt.Errorf("environment variable %s: %w: %s",
-			idEnvKey, ErrSystemIDNotValid, err)
-	} else if idUint64 > max {
-		return nil, fmt.Errorf("environment variable %s: %w: %d: must be between 0 and %d",
-			idEnvKey, ErrSystemIDNotValid, idUint64, max)
-	}
-
-	return uint32Ptr(uint32(idUint64)), nil
-}

internal/configuration/sources/env/system_test.go

@@ -1,88 +0,0 @@
-package env
-
-import (
-	"testing"
-
-	"github.com/stretchr/testify/assert"
-)
-
-func Test_Reader_readID(t *testing.T) {
-	t.Parallel()
-
-	testCases := map[string]struct {
-		keyPrefix      string
-		keyValue       string
-		retroKeyPrefix string
-		retroValue     string
-		id             *uint32
-		errWrapped     error
-		errMessage     string
-	}{
-		"empty string": {
-			keyPrefix:      "ID",
-			retroKeyPrefix: "RETRO_ID",
-		},
-		"invalid string": {
-			keyPrefix:      "ID",
-			keyValue:       "invalid",
-			retroKeyPrefix: "RETRO_ID",
-			errWrapped:     ErrSystemIDNotValid,
-			errMessage: `environment variable IDTest_Reader_readID/invalid_string: ` +
-				`system ID is not valid: ` +
-				`strconv.ParseUint: parsing "invalid": invalid syntax`,
-		},
-		"negative number": {
-			keyPrefix:      "ID",
-			keyValue:       "-1",
-			retroKeyPrefix: "RETRO_ID",
-			errWrapped:     ErrSystemIDNotValid,
-			errMessage: `environment variable IDTest_Reader_readID/negative_number: ` +
-				`system ID is not valid: ` +
-				`strconv.ParseUint: parsing "-1": invalid syntax`,
-		},
-		"id 1000": {
-			keyPrefix:      "ID",
-			keyValue:       "1000",
-			retroKeyPrefix: "RETRO_ID",
-			id:             uint32Ptr(1000),
-		},
-		"max id": {
-			keyPrefix:      "ID",
-			keyValue:       "4294967295",
-			retroKeyPrefix: "RETRO_ID",
-			id:             uint32Ptr(4294967295),
-		},
-		"above max id": {
-			keyPrefix:      "ID",
-			keyValue:       "4294967296",
-			retroKeyPrefix: "RETRO_ID",
-			errWrapped:     ErrSystemIDNotValid,
-			errMessage: `environment variable IDTest_Reader_readID/above_max_id: ` +
-				`system ID is not valid: 4294967296: must be between 0 and 4294967295`,
-		},
-	}
-
-	for name, testCase := range testCases {
-		testCase := testCase
-		t.Run(name, func(t *testing.T) {
-			t.Parallel()
-
-			suffix := t.Name()
-			key := testCase.keyPrefix + suffix
-			retroKey := testCase.retroKeyPrefix + suffix
-
-			setTestEnv(t, key, testCase.keyValue)
-			setTestEnv(t, retroKey, testCase.retroValue)
-
-			reader := &Reader{}
-			id, err := reader.readID(key, retroKey)
-
-			assert.ErrorIs(t, err, testCase.errWrapped)
-			if err != nil {
-				assert.EqualError(t, err, testCase.errMessage)
-			}
-
-			assert.Equal(t, testCase.id, id)
-		})
-	}
-}

internal/configuration/sources/env/unbound.go

@@ -1,37 +1,35 @@
 package env
 
 import (
-	"fmt"
-
 	"github.com/qdm12/gluetun/internal/configuration/settings"
 )
 
-func readUnbound() (unbound settings.Unbound, err error) {
-	unbound.Providers = envToCSV("DOT_PROVIDERS")
+func (s *Source) readUnbound() (unbound settings.Unbound, err error) {
+	unbound.Providers = s.env.CSV("DOT_PROVIDERS")
 
-	unbound.Caching, err = envToBoolPtr("DOT_CACHING")
+	unbound.Caching, err = s.env.BoolPtr("DOT_CACHING")
 	if err != nil {
-		return unbound, fmt.Errorf("environment variable DOT_CACHING: %w", err)
+		return unbound, err
 	}
 
-	unbound.IPv6, err = envToBoolPtr("DOT_IPV6")
+	unbound.IPv6, err = s.env.BoolPtr("DOT_IPV6")
 	if err != nil {
-		return unbound, fmt.Errorf("environment variable DOT_IPV6: %w", err)
+		return unbound, err
 	}
 
-	unbound.VerbosityLevel, err = envToUint8Ptr("DOT_VERBOSITY")
+	unbound.VerbosityLevel, err = s.env.Uint8Ptr("DOT_VERBOSITY")
 	if err != nil {
-		return unbound, fmt.Errorf("environment variable DOT_VERBOSITY: %w", err)
+		return unbound, err
 	}
 
-	unbound.VerbosityDetailsLevel, err = envToUint8Ptr("DOT_VERBOSITY_DETAILS")
+	unbound.VerbosityDetailsLevel, err = s.env.Uint8Ptr("DOT_VERBOSITY_DETAILS")
 	if err != nil {
-		return unbound, fmt.Errorf("environment variable DOT_VERBOSITY_DETAILS: %w", err)
+		return unbound, err
 	}
 
-	unbound.ValidationLogLevel, err = envToUint8Ptr("DOT_VALIDATION_LOGLEVEL")
+	unbound.ValidationLogLevel, err = s.env.Uint8Ptr("DOT_VALIDATION_LOGLEVEL")
 	if err != nil {
-		return unbound, fmt.Errorf("environment variable DOT_VALIDATION_LOGLEVEL: %w", err)
+		return unbound, err
 	}
 
 	return unbound, nil