fix(vpnsecure): allow empty OpenVPN user+password

2022-09-11 20:18:42 +00:00
382 changed files with 69547 additions and 156702 deletions
--- a/.devcontainer/Dockerfile
+++ b/.devcontainer/Dockerfile
@@ -1,2 +1,2 @@
 FROM qmcgaw/godevcontainer
-RUN apk add wireguard-tools htop openssl
+RUN apk add wireguard-tools htop
--- a/.devcontainer/README.md
+++ b/.devcontainer/README.md
@@ -9,21 +9,17 @@ 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

@@ -33,9 +29,13 @@ 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 `/root/.welcome.sh` to replace the [current welcome script](shell/.welcome.sh).
+You can bind mount a shell script to `/home/vscode/.welcome.sh` to replace the [current welcome script](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). You can also now do it directly with VSCode without restarting the container.
+To access a port from your host to your development container, publish a port in [docker-compose.yml](docker-compose.yml).

 ### Run other services

--- a/.devcontainer/devcontainer.json
+++ b/.devcontainer/devcontainer.json
@@ -1,73 +1,82 @@
-{
-    "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
-            }
-        }
-    }
+{
+    "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
+    }
 }
--- a/.devcontainer/docker-compose.yml
+++ b/.devcontainer/docker-compose.yml
@@ -1,28 +1,32 @@
-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" ]
+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"
--- a/.github/ISSUE_TEMPLATE/bug.yml
+++ b/.github/ISSUE_TEMPLATE/bug.yml
@@ -40,7 +40,6 @@ body:
    attributes:
      label: VPN service provider
      options:
-        - AirVPN
        - Custom
        - Cyberghost
        - ExpressVPN
--- a/.github/labels.yml
+++ b/.github/labels.yml
@@ -1,13 +1,18 @@
-# Temporary status
- name: "🗯️ Waiting for feedback"
-  color: "aadefa"
+- 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"
  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"
@@ -17,18 +22,7 @@
  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: ""
@@ -95,9 +89,6 @@
  description: ""

 # Problem category
- name: "Config problem"
-  color: "ffc7ea"
-  description: ""
 - name: "Openvpn"
  color: "ffc7ea"
  description: ""
@@ -110,15 +101,6 @@
 - 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: ""
--- a/.github/workflows/ci-skip.yml
+++ b/.github/workflows/ci-skip.yml
@@ -14,6 +14,8 @@ on:
      - go.mod
      - go.sum
  pull_request:
+    branches:
+      - master
    paths-ignore:
      - .github/workflows/ci.yml
      - cmd/**
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -17,6 +17,8 @@ on:
      - go.mod
      - go.sum
  pull_request:
+    branches:
+      - master
    paths:
      - .github/workflows/ci.yml
      - cmd/**
@@ -43,8 +45,6 @@ jobs:
        with:
          locale: "US"
          level: error
-          exclude: |
-            ./internal/storage/servers.json

      - name: Linting
        run: docker build --target lint .
@@ -91,7 +91,6 @@ jobs:
    permissions:
      actions: read
      contents: read
-      packages: write
    runs-on: ubuntu-latest
    steps:
      - uses: actions/checkout@v3
@@ -105,7 +104,6 @@ jobs:
          flavor: |
            latest=${{ github.ref == format('refs/heads/{0}', github.event.repository.default_branch) }}
          images: |
-            ghcr.io/qdm12/gluetun
            qmcgaw/gluetun
            qmcgaw/private-internet-access
          tags: |
@@ -123,18 +121,12 @@ jobs:
          username: qmcgaw
          password: ${{ secrets.DOCKERHUB_PASSWORD }}

-      - uses: docker/login-action@v2
-        with:
-          registry: ghcr.io
-          username: qdm12
-          password: ${{ github.token }}
-
      - name: Short commit
        id: shortcommit
        run: echo "::set-output name=value::$(git rev-parse --short HEAD)"

      - name: Build and push final image
-        uses: docker/build-push-action@v4.1.1
+        uses: docker/build-push-action@v3.1.1
        with:
          platforms: linux/amd64,linux/386,linux/arm64,linux/arm/v6,linux/arm/v7,linux/ppc64le
          labels: ${{ steps.meta.outputs.labels }}
--- a/.golangci.yml
+++ b/.golangci.yml
@@ -29,10 +29,6 @@ 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

 linters:
  enable:
@@ -46,7 +42,6 @@ linters:
    - decorder
    - dogsled
    - dupl
-    - dupword
    - durationcheck
    - errchkjson
    - errname
@@ -55,7 +50,6 @@ linters:
    - exportloopref
    - forcetypeassert
    - gci
-    - gocheckcompilerdirectives
    - gochecknoglobals
    - gochecknoinits
    - gocognit
@@ -70,7 +64,6 @@ linters:
    - gomoddirectives
    - goprintffuncname
    - gosec
-    - gosmopolitan
    - grouper
    - importas
    - interfacebloat
@@ -78,9 +71,7 @@ linters:
    - lll
    - maintidx
    - makezero
-    - mirror
    - misspell
-    - musttag
    - nakedret
    - nestif
    - nilerr
@@ -88,7 +79,6 @@ linters:
    - noctx
    - nolintlint
    - nosprintfhostport
-    - paralleltest
    - prealloc
    - predeclared
    - promlinter
@@ -96,7 +86,6 @@ linters:
    - revive
    - rowserrcheck
    - sqlclosecheck
-    - tagalign
    - tenv
    - thelper
    - tparallel
@@ -105,7 +94,6 @@ linters:
    - usestdlibvars
    - wastedassign
    - whitespace
-    - zerologlint

 run:
  skip-dirs:
--- a/.vscode/extensions.json
+++ b/.vscode/extensions.json
@@ -1,8 +0,0 @@
-{
-  // This list should be kept to the strict minimum
-  // to develop this project.
-  "recommendations": [
-    "golang.go",
-    "davidanson.vscode-markdownlint",
-  ],
-}
--- a/.vscode/launch.json
+++ b/.vscode/launch.json
@@ -5,11 +5,11 @@
            "name": "Update a VPN provider servers data",
            "type": "go",
            "request": "launch",
-            "cwd": "${workspaceFolder}",
+            "mode": "debug",
            "program": "cmd/gluetun/main.go",
            "args": [
                "update",
-                "${input:updateMode}",
+                "-enduser",
                "-providers",
                "${input:provider}"
            ],
@@ -20,16 +20,6 @@
            "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"
-        },
+        }
    ]
 }
--- a/.vscode/settings.json
+++ b/.vscode/settings.json
@@ -1,29 +0,0 @@
-{
-  // 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"
-}
--- a/24
+++ b/24
@@ -1,8 +1,8 @@
-ARG ALPINE_VERSION=3.18
-ARG GO_ALPINE_VERSION=3.18
-ARG GO_VERSION=1.20
+ARG ALPINE_VERSION=3.16
+ARG GO_ALPINE_VERSION=3.16
+ARG GO_VERSION=1.17
 ARG XCPUTRANSLATE_VERSION=v0.6.0
-ARG GOLANGCI_LINT_VERSION=v1.53.2
+ARG GOLANGCI_LINT_VERSION=v1.49.0
 ARG MOCKGEN_VERSION=v1.6.0
 ARG BUILDPLATFORM=linux/amd64

@@ -91,14 +91,13 @@ ENV VPN_SERVICE_PROVIDER=pia \
    OPENVPN_CIPHERS= \
    OPENVPN_AUTH= \
    OPENVPN_PROCESS_USER= \
+    OPENVPN_IPV6=off \
    OPENVPN_CUSTOM_CONFIG= \
    # Wireguard
    WIREGUARD_PRIVATE_KEY= \
    WIREGUARD_PRESHARED_KEY= \
    WIREGUARD_PUBLIC_KEY= \
    WIREGUARD_ADDRESSES= \
-    WIREGUARD_MTU=1400 \
-    WIREGUARD_IMPLEMENTATION=auto \
    # VPN server filtering
    SERVER_REGIONS= \
    SERVER_COUNTRIES= \
@@ -109,8 +108,8 @@ ENV VPN_SERVICE_PROVIDER=pia \
    OWNED_ONLY=no \
    # # Private Internet Access only:
    PRIVATE_INTERNET_ACCESS_OPENVPN_ENCRYPTION_PRESET= \
-    VPN_PORT_FORWARDING=off \
-    VPN_PORT_FORWARDING_STATUS_FILE="/tmp/gluetun/forwarded_port" \
+    PRIVATE_INTERNET_ACCESS_VPN_PORT_FORWARDING=off \
+    PRIVATE_INTERNET_ACCESS_VPN_PORT_FORWARDING_STATUS_FILE="/tmp/gluetun/forwarded_port" \
    # # Cyberghost only:
    OPENVPN_CERT= \
    OPENVPN_KEY= \
@@ -142,7 +141,6 @@ 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
@@ -199,12 +197,12 @@ 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 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 && \
+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 && \
    apk del openvpn && \
    apk add --no-cache --update openvpn ca-certificates iptables ip6tables unbound tzdata && \
-    mv /usr/sbin/openvpn /usr/sbin/openvpn2.6 && \
+    mv /usr/sbin/openvpn /usr/sbin/openvpn2.5 && \
    # 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 && \
--- a/README.md
+++ b/README.md
@@ -1,130 +1,125 @@
-# Gluetun VPN client
-
-Lightweight swiss-knife-like VPN client to multiple VPN service providers
-
-![Title image](https://raw.githubusercontent.com/qdm12/gluetun/master/title.svg)
-
-[![Build status](https://github.com/qdm12/gluetun/actions/workflows/ci.yml/badge.svg)](https://github.com/qdm12/gluetun/actions/workflows/ci.yml)
-
-[![Docker pulls qmcgaw/gluetun](https://img.shields.io/docker/pulls/qmcgaw/gluetun.svg)](https://hub.docker.com/r/qmcgaw/gluetun)
-[![Docker pulls qmcgaw/private-internet-access](https://img.shields.io/docker/pulls/qmcgaw/private-internet-access.svg)](https://hub.docker.com/r/qmcgaw/gluetun)
-
-[![Docker stars qmcgaw/gluetun](https://img.shields.io/docker/stars/qmcgaw/gluetun.svg)](https://hub.docker.com/r/qmcgaw/gluetun)
-[![Docker stars qmcgaw/private-internet-access](https://img.shields.io/docker/stars/qmcgaw/private-internet-access.svg)](https://hub.docker.com/r/qmcgaw/gluetun)
-
-![Last release](https://img.shields.io/github/release/qdm12/gluetun?label=Last%20release)
-![Last Docker tag](https://img.shields.io/docker/v/qmcgaw/gluetun?sort=semver&label=Last%20Docker%20tag)
-[![Last release size](https://img.shields.io/docker/image-size/qmcgaw/gluetun?sort=semver&label=Last%20released%20image)](https://hub.docker.com/r/qmcgaw/gluetun/tags?page=1&ordering=last_updated)
-![GitHub last release date](https://img.shields.io/github/release-date/qdm12/gluetun?label=Last%20release%20date)
-![Commits since release](https://img.shields.io/github/commits-since/qdm12/gluetun/latest?sort=semver)
-
-[![Latest size](https://img.shields.io/docker/image-size/qmcgaw/gluetun/latest?label=Latest%20image)](https://hub.docker.com/r/qmcgaw/gluetun/tags)
-
-[![GitHub last commit](https://img.shields.io/github/last-commit/qdm12/gluetun.svg)](https://github.com/qdm12/gluetun/commits/master)
-[![GitHub commit activity](https://img.shields.io/github/commit-activity/y/qdm12/gluetun.svg)](https://github.com/qdm12/gluetun/graphs/contributors)
-[![GitHub closed PRs](https://img.shields.io/github/issues-pr-closed/qdm12/gluetun.svg)](https://github.com/qdm12/gluetun/pulls?q=is%3Apr+is%3Aclosed)
-[![GitHub issues](https://img.shields.io/github/issues/qdm12/gluetun.svg)](https://github.com/qdm12/gluetun/issues)
-[![GitHub closed issues](https://img.shields.io/github/issues-closed/qdm12/gluetun.svg)](https://github.com/qdm12/gluetun/issues?q=is%3Aissue+is%3Aclosed)
-
-[![Lines of code](https://img.shields.io/tokei/lines/github/qdm12/gluetun)](https://github.com/qdm12/gluetun)
-![Code size](https://img.shields.io/github/languages/code-size/qdm12/gluetun)
-![GitHub repo size](https://img.shields.io/github/repo-size/qdm12/gluetun)
-![Go version](https://img.shields.io/github/go-mod/go-version/qdm12/gluetun)
-
-![Visitors count](https://visitor-badge.laobi.icu/badge?page_id=gluetun.readme)
-
-## Quick links
-
- [Setup](#setup)
- [Features](#features)
- Problem?
-  - [Check the Wiki](https://github.com/qdm12/gluetun/wiki)
-  - [Start a discussion](https://github.com/qdm12/gluetun/discussions)
-  - [Fix the Unraid template](https://github.com/qdm12/gluetun/discussions/550)
- Suggestion?
-  - [Create an issue](https://github.com/qdm12/gluetun/issues)
-  - [Join the Slack channel](https://join.slack.com/t/qdm12/shared_invite/enQtOTE0NjcxNTM1ODc5LTYyZmVlOTM3MGI4ZWU0YmJkMjUxNmQ4ODQ2OTAwYzMxMTlhY2Q1MWQyOWUyNjc2ODliNjFjMDUxNWNmNzk5MDk)
- Happy?
-  - Sponsor me on [github.com/sponsors/qdm12](https://github.com/sponsors/qdm12)
-  - Donate to [paypal.me/qmcgaw](https://www.paypal.me/qmcgaw)
-  - Drop me [an email](mailto:quentin.mcgaw@gmail.com)
- **Want to add a VPN provider?** check [Development](https://github.com/qdm12/gluetun/wiki/Development) and [Add a provider](https://github.com/qdm12/gluetun/wiki/Add-a-provider)
- Video:
-
-  [![Video Gif](https://i.imgur.com/CetWunc.gif)](https://youtu.be/0F6I03LQcI4)
-
- [Substack Console interview](https://console.substack.com/p/console-72)
-
-## Features
-
- Based on Alpine 3.18 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 **Mullvad**, **Ivpn**, **Surfshark** and **Windscribe**
-  - For **ProtonVPN**, **PureVPN**, **Torguard**, **VPN Unlimited** and **WeVPN** using [the custom provider](https://github.com/qdm12/gluetun/wiki/Custom-provider)
-  - For custom Wireguard configurations using [the custom provider](https://github.com/qdm12/gluetun/wiki/Custom-provider)
-  - More in progress, see [#134](https://github.com/qdm12/gluetun/issues/134)
- DNS over TLS baked in with service provider(s) of your choice
- DNS fine blocking of malicious/ads/surveillance hostnames and IP addresses, with live update every 24 hours
- Choose the vpn network protocol, `udp` or `tcp`
- Built in firewall kill switch to allow traffic only with needed the VPN servers and LAN devices
- Built in Shadowsocks proxy (protocol based on SOCKS5 with an encryption layer, tunnels TCP+UDP)
- Built in HTTP proxy (tunnels HTTP and HTTPS through TCP)
- [Connect other containers to it](https://github.com/qdm12/gluetun/wiki/Connect-a-container-to-gluetun)
- [Connect LAN devices to it](https://github.com/qdm12/gluetun/wiki/Connect-a-LAN-device-to-gluetun)
- Compatible with amd64, i686 (32 bit), **ARM** 64 bit, ARM 32 bit v6 and v7, and even ppc64le 🎆
- [Custom VPN server side port forwarding for Private Internet Access](https://github.com/qdm12/gluetun/wiki/Private-internet-access#vpn-server-port-forwarding)
- Possibility of split horizon DNS by selecting multiple DNS over TLS providers
- Unbound subprogram drops root privileges once launched
- Can work as a Kubernetes sidecar container, thanks @rorph
-
-## Setup
-
-🎉 There are now instructions specific to each VPN provider with examples to help you get started as quickly as possible!
-
-Go to the [Wiki](https://github.com/qdm12/gluetun/wiki)!
-
-[🐛 Found a bug in the Wiki?!](https://github.com/qdm12/gluetun/issues/new?assignees=&labels=%F0%9F%93%84+Wiki+issue&template=wiki+issue.yml&title=Wiki+issue%3A+)
-
-Here's a docker-compose.yml for the laziest:
-
-```yml
-version: "3"
-services:
-  gluetun:
-    image: qmcgaw/gluetun
-    # container_name: gluetun
-    # line above must be uncommented to allow external containers to connect. See https://github.com/qdm12/gluetun/wiki/Connect-a-container-to-gluetun#external-container-to-gluetun
-    cap_add:
-      - NET_ADMIN
-    devices:
-      - /dev/net/tun:/dev/net/tun
-    ports:
-      - 8888:8888/tcp # HTTP proxy
-      - 8388:8388/tcp # Shadowsocks
-      - 8388:8388/udp # Shadowsocks
-    volumes:
-      - /yourpath:/gluetun
-    environment:
-      # See https://github.com/qdm12/gluetun/wiki
-      - VPN_SERVICE_PROVIDER=ivpn
-      - VPN_TYPE=openvpn
-      # OpenVPN:
-      - OPENVPN_USER=
-      - OPENVPN_PASSWORD=
-      # Wireguard:
-      # - WIREGUARD_PRIVATE_KEY=wOEI9rqqbDwnN8/Bpp22sVz48T71vJ4fYmFWujulwUU=
-      # - WIREGUARD_ADDRESSES=10.64.222.21/32
-      # Timezone for accurate log times
-      - TZ=
-      # Server list updater. See https://github.com/qdm12/gluetun/wiki/Updating-Servers#periodic-update
-      - UPDATER_PERIOD=
-      - UPDATER_VPN_SERVICE_PROVIDERS=
-```
-
-🆕 Image also available as `ghcr.io/qdm12/gluetun`
-
-## License
-
-[![MIT](https://img.shields.io/github/license/qdm12/gluetun)](https://github.com/qdm12/gluetun/master/LICENSE)
+# Gluetun VPN client
+
+Lightweight swiss-knife-like VPN client to multiple VPN service providers
+
+![Title image](https://raw.githubusercontent.com/qdm12/gluetun/master/title.svg)
+
+[![Build status](https://github.com/qdm12/gluetun/actions/workflows/ci.yml/badge.svg)](https://github.com/qdm12/gluetun/actions/workflows/ci.yml)
+
+[![Docker pulls qmcgaw/gluetun](https://img.shields.io/docker/pulls/qmcgaw/gluetun.svg)](https://hub.docker.com/r/qmcgaw/gluetun)
+[![Docker pulls qmcgaw/private-internet-access](https://img.shields.io/docker/pulls/qmcgaw/private-internet-access.svg)](https://hub.docker.com/r/qmcgaw/gluetun)
+
+[![Docker stars qmcgaw/gluetun](https://img.shields.io/docker/stars/qmcgaw/gluetun.svg)](https://hub.docker.com/r/qmcgaw/gluetun)
+[![Docker stars qmcgaw/private-internet-access](https://img.shields.io/docker/stars/qmcgaw/private-internet-access.svg)](https://hub.docker.com/r/qmcgaw/gluetun)
+
+![Last release](https://img.shields.io/github/release/qdm12/gluetun?label=Last%20release)
+![Last Docker tag](https://img.shields.io/docker/v/qmcgaw/gluetun?sort=semver&label=Last%20Docker%20tag)
+[![Last release size](https://img.shields.io/docker/image-size/qmcgaw/gluetun?sort=semver&label=Last%20released%20image)](https://hub.docker.com/r/qmcgaw/gluetun/tags?page=1&ordering=last_updated)
+![GitHub last release date](https://img.shields.io/github/release-date/qdm12/gluetun?label=Last%20release%20date)
+![Commits since release](https://img.shields.io/github/commits-since/qdm12/gluetun/latest?sort=semver)
+
+[![Latest size](https://img.shields.io/docker/image-size/qmcgaw/gluetun/latest?label=Latest%20image)](https://hub.docker.com/r/qmcgaw/gluetun/tags)
+
+[![GitHub last commit](https://img.shields.io/github/last-commit/qdm12/gluetun.svg)](https://github.com/qdm12/gluetun/commits/master)
+[![GitHub commit activity](https://img.shields.io/github/commit-activity/y/qdm12/gluetun.svg)](https://github.com/qdm12/gluetun/graphs/contributors)
+[![GitHub closed PRs](https://img.shields.io/github/issues-pr-closed/qdm12/gluetun.svg)](https://github.com/qdm12/gluetun/pulls?q=is%3Apr+is%3Aclosed)
+[![GitHub issues](https://img.shields.io/github/issues/qdm12/gluetun.svg)](https://github.com/qdm12/gluetun/issues)
+[![GitHub closed issues](https://img.shields.io/github/issues-closed/qdm12/gluetun.svg)](https://github.com/qdm12/gluetun/issues?q=is%3Aissue+is%3Aclosed)
+
+[![Lines of code](https://img.shields.io/tokei/lines/github/qdm12/gluetun)](https://github.com/qdm12/gluetun)
+![Code size](https://img.shields.io/github/languages/code-size/qdm12/gluetun)
+![GitHub repo size](https://img.shields.io/github/repo-size/qdm12/gluetun)
+![Go version](https://img.shields.io/github/go-mod/go-version/qdm12/gluetun)
+
+![Visitors count](https://visitor-badge.laobi.icu/badge?page_id=gluetun.readme)
+
+## Quick links
+
+- [Setup](#Setup)
+- [Features](#Features)
+- Problem?
+  - [Check the Wiki](https://github.com/qdm12/gluetun/wiki)
+  - [Start a discussion](https://github.com/qdm12/gluetun/discussions)
+  - [Fix the Unraid template](https://github.com/qdm12/gluetun/discussions/550)
+- Suggestion?
+  - [Create an issue](https://github.com/qdm12/gluetun/issues)
+  - [Join the Slack channel](https://join.slack.com/t/qdm12/shared_invite/enQtOTE0NjcxNTM1ODc5LTYyZmVlOTM3MGI4ZWU0YmJkMjUxNmQ4ODQ2OTAwYzMxMTlhY2Q1MWQyOWUyNjc2ODliNjFjMDUxNWNmNzk5MDk)
+- Happy?
+  - Sponsor me on [github.com/sponsors/qdm12](https://github.com/sponsors/qdm12)
+  - Donate to [paypal.me/qmcgaw](https://www.paypal.me/qmcgaw)
+  - Drop me [an email](mailto:quentin.mcgaw@gmail.com)
+- **Want to add a VPN provider?** check [Development](https://github.com/qdm12/gluetun/wiki/Development) and [Add a provider](https://github.com/qdm12/gluetun/wiki/Add-a-provider)
+- Video:
+
+  [![Video Gif](https://i.imgur.com/CetWunc.gif)](https://youtu.be/0F6I03LQcI4)
+
+- [Substack Console interview](https://console.substack.com/p/console-72)
+
+## Features
+
+- Based on Alpine 3.16 for a small Docker image of 29MB
+- Supports: **Cyberghost**, **ExpressVPN**, **FastestVPN**, **HideMyAss**, **IPVanish**, **IVPN**, **Mullvad**, **NordVPN**, **Perfect Privacy**, **Privado**, **Private Internet Access**, **PrivateVPN**, **ProtonVPN**, **PureVPN**,  **SlickVPN**, **Surfshark**, **TorGuard**, **VPNSecure.me**, **VPNUnlimited**, **Vyprvpn**, **WeVPN**, **Windscribe** servers
+- Supports OpenVPN for all providers listed
+- Supports Wireguard both kernelspace and userspace
+  - For **Mullvad**, **Ivpn** and **Windscribe**
+  - For **Torguard**, **VPN Unlimited** and **WeVPN** using [the custom provider](https://github.com/qdm12/gluetun/wiki/Custom-provider)
+  - For custom Wireguard configurations using [the custom provider](https://github.com/qdm12/gluetun/wiki/Custom-provider)
+  - More in progress, see [#134](https://github.com/qdm12/gluetun/issues/134)
+- DNS over TLS baked in with service provider(s) of your choice
+- DNS fine blocking of malicious/ads/surveillance hostnames and IP addresses, with live update every 24 hours
+- Choose the vpn network protocol, `udp` or `tcp`
+- Built in firewall kill switch to allow traffic only with needed the VPN servers and LAN devices
+- Built in Shadowsocks proxy (protocol based on SOCKS5 with an encryption layer, tunnels TCP+UDP)
+- Built in HTTP proxy (tunnels HTTP and HTTPS through TCP)
+- [Connect other containers to it](https://github.com/qdm12/gluetun/wiki/Connect-a-container-to-gluetun)
+- [Connect LAN devices to it](https://github.com/qdm12/gluetun/wiki/Connect-a-LAN-device-to-gluetun)
+- Compatible with amd64, i686 (32 bit), **ARM** 64 bit, ARM 32 bit v6 and v7, and even ppc64le 🎆
+- [Custom VPN server side port forwarding for Private Internet Access](https://github.com/qdm12/gluetun/wiki/Private-internet-access#vpn-server-port-forwarding)
+- Possibility of split horizon DNS by selecting multiple DNS over TLS providers
+- Unbound subprogram drops root privileges once launched
+- Can work as a Kubernetes sidecar container, thanks @rorph
+
+## Setup
+
+🎉 There are now instructions specific to each VPN provider with examples to help you get started as quickly as possible!
+
+Go to the [Wiki](https://github.com/qdm12/gluetun/wiki)!
+
+[🐛 Found a bug in the Wiki?!](https://github.com/qdm12/gluetun/issues/new?assignees=&labels=%F0%9F%93%84+Wiki+issue&template=wiki+issue.yml&title=Wiki+issue%3A+)
+
+Here's a docker-compose.yml for the laziest:
+
+```yml
+version: "3"
+services:
+  gluetun:
+    image: qmcgaw/gluetun
+    # container_name: gluetun
+    # line above must be uncommented to allow external containers to connect. See https://github.com/qdm12/gluetun/wiki/Connect-a-container-to-gluetun#external-container-to-gluetun
+    cap_add:
+      - NET_ADMIN
+    devices:
+      - /dev/net/tun:/dev/net/tun
+    ports:
+      - 8888:8888/tcp # HTTP proxy
+      - 8388:8388/tcp # Shadowsocks
+      - 8388:8388/udp # Shadowsocks
+    volumes:
+      - /yourpath:/gluetun
+    environment:
+      # See https://github.com/qdm12/gluetun/wiki
+      - VPN_SERVICE_PROVIDER=ivpn
+      - VPN_TYPE=openvpn
+      # OpenVPN:
+      - OPENVPN_USER=
+      - OPENVPN_PASSWORD=
+      # Wireguard:
+      # - WIREGUARD_PRIVATE_KEY=wOEI9rqqbDwnN8/Bpp22sVz48T71vJ4fYmFWujulwUU=
+      # - WIREGUARD_ADDRESSES=10.64.222.21/32
+      # Timezone for accurate log times
+      - TZ=
+```
+
+## License
+
+[![MIT](https://img.shields.io/github/license/qdm12/gluetun)](https://github.com/qdm12/gluetun/master/LICENSE)
--- a/cmd/gluetun/main.go
+++ b/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/settings"
+	"github.com/qdm12/gluetun/internal/configuration/sources"
 	"github.com/qdm12/gluetun/internal/configuration/sources/env"
 	"github.com/qdm12/gluetun/internal/configuration/sources/files"
-	mux "github.com/qdm12/gluetun/internal/configuration/sources/merge"
+	"github.com/qdm12/gluetun/internal/configuration/sources/mux"
 	"github.com/qdm12/gluetun/internal/configuration/sources/secrets"
 	"github.com/qdm12/gluetun/internal/constants"
 	"github.com/qdm12/gluetun/internal/dns"
@@ -77,8 +77,7 @@ func main() {

 	args := os.Args
 	tun := tun.New()
-	netLinkDebugLogger := logger.New(log.SetComponent("netlink"))
-	netLinker := netlink.New(netLinkDebugLogger)
+	netLinker := netlink.New()
 	cli := cli.New()
 	cmder := command.NewCmder()

@@ -92,13 +91,12 @@ func main() {
 		errorCh <- _main(ctx, buildInfo, args, logger, muxReader, tun, netLinker, cmder, cli)
 	}()

-	var err error
 	select {
 	case signal := <-signalCh:
 		fmt.Println("")
 		logger.Warn("Caught OS signal " + signal.String() + ", shutting down")
 		cancel()
-	case err = <-errorCh:
+	case err := <-errorCh:
 		close(errorCh)
 		if err == nil { // expected exit such as healthcheck
 			os.Exit(0)
@@ -110,27 +108,18 @@ func main() {
 	const shutdownGracePeriod = 5 * time.Second
 	timer := time.NewTimer(shutdownGracePeriod)
 	select {
-	case shutdownErr := <-errorCh:
+	case <-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 (
@@ -139,7 +128,7 @@ var (

 //nolint:gocognit,gocyclo,maintidx
 func _main(ctx context.Context, buildInfo models.BuildInformation,
-	args []string, logger log.LoggerInterface, source Source,
+	args []string, logger log.LoggerInterface, source sources.Source,
 	tun Tun, netLinker netLinker, cmder command.RunStarter,
 	cli clier) error {
 	if len(args) > 1 { // cli operation
@@ -149,7 +138,7 @@ func _main(ctx context.Context, buildInfo models.BuildInformation,
 		case "clientkey":
 			return cli.ClientKey(args[2:])
 		case "openvpnconfig":
-			return cli.OpenvpnConfig(logger, source, netLinker)
+			return cli.OpenvpnConfig(logger, source)
 		case "update":
 			return cli.Update(ctx, args[2:], logger)
 		case "format-servers":
@@ -190,7 +179,6 @@ 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
@@ -232,12 +220,7 @@ func _main(ctx context.Context, buildInfo models.BuildInformation,
 		return err
 	}

-	ipv6Supported, err := netLinker.IsIPv6Supported()
-	if err != nil {
-		return fmt.Errorf("checking for IPv6 support: %w", err)
-	}
-
-	err = allSettings.Validate(storage, ipv6Supported)
+	err = allSettings.Validate(storage)
 	if err != nil {
 		return err
 	}
@@ -245,7 +228,7 @@ 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("creating Pprof server: %w", err)
+		return fmt.Errorf("cannot create Pprof server: %w", err)
 	}

 	puid, pgid := int(*allSettings.System.PUID), int(*allSettings.System.PGID)
@@ -264,8 +247,8 @@ 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)
@@ -277,10 +260,6 @@ 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
 	}
@@ -291,7 +270,7 @@ func _main(ctx context.Context, buildInfo models.BuildInformation,
 	const defaultUsername = "nonrootuser"
 	nonRootUsername, err := alpineConf.CreateUser(defaultUsername, puid)
 	if err != nil {
-		return fmt.Errorf("creating user: %w", err)
+		return fmt.Errorf("cannot create user: %w", err)
 	}
 	if nonRootUsername != defaultUsername {
 		logger.Info("using existing username " + nonRootUsername + " corresponding to user id " + fmt.Sprint(puid))
@@ -309,7 +288,7 @@ 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("setting up routing: %w", err)
+		return fmt.Errorf("cannot setup routing: %w", err)
 	}
 	defer func() {
 		routingLogger.Info("routing cleanup...")
@@ -325,11 +304,6 @@ 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...")
@@ -365,14 +339,11 @@ func _main(ctx context.Context, buildInfo models.BuildInformation,
 	tickersGroupHandler := goshutdown.NewGroupHandler("tickers", defaultGroupOptions...)
 	otherGroupHandler := goshutdown.NewGroupHandler("other", defaultGroupOptions...)

-	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
-	}
+	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,
@@ -418,7 +389,7 @@ func _main(ctx context.Context, buildInfo models.BuildInformation,
 		httpClient, unzipper, parallelResolver, ipFetcher, openvpnFileExtractor)

 	vpnLogger := logger.New(log.SetComponent("vpn"))
-	vpnLooper := vpn.NewLoop(allSettings.VPN, ipv6Supported, allSettings.Firewall.VPNInputPorts,
+	vpnLooper := vpn.NewLoop(allSettings.VPN, allSettings.Firewall.VPNInputPorts,
 		providers, storage, ovpnConf, netLinker, firewallConf, routingConf, portForwardLooper,
 		cmder, publicIPLooper, unboundLooper, vpnLogger, httpClient,
 		buildInfo, *allSettings.Version.Enabled)
@@ -460,10 +431,9 @@ func _main(ctx context.Context, buildInfo models.BuildInformation,
 		"http server", goroutine.OptionTimeout(defaultShutdownTimeout))
 	httpServer, err := server.New(httpServerCtx, controlServerAddress, controlServerLogging,
 		logger.New(log.SetComponent("http server")),
-		buildInfo, vpnLooper, portForwardLooper, unboundLooper, updaterLooper, publicIPLooper,
-		storage, ipv6Supported)
+		buildInfo, vpnLooper, portForwardLooper, unboundLooper, updaterLooper, publicIPLooper, storage)
 	if err != nil {
-		return fmt.Errorf("setting up control server: %w", err)
+		return fmt.Errorf("cannot setup control server: %w", err)
 	}
 	httpServerReady := make(chan struct{})
 	go httpServer.Run(httpServerCtx, httpServerReady, httpServerDone)
@@ -510,7 +480,7 @@ func printVersions(ctx context.Context, logger infoer,
 	for _, element := range elements {
 		version, err := element.getVersion(ctx)
 		if err != nil {
-			return fmt.Errorf("getting %s version: %w", element.name, err)
+			return err
 		}
 		logger.Info(element.name + " version: " + version)
 	}
@@ -524,44 +494,43 @@ type netLinker interface {
 	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)
-	AddrReplace(link netlink.Link, addr netlink.Addr) error
+	AddrAdd(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
+	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
 }

 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) (linkIndex int, err error)
+	LinkAdd(link netlink.Link) (err error)
 	LinkDel(link netlink.Link) (err error)
-	LinkSetUp(link netlink.Link) (linkIndex int, err error)
+	LinkSetUp(link netlink.Link) (err error)
 	LinkSetDown(link netlink.Link) (err error)
 }

 type clier interface {
 	ClientKey(args []string) error
 	FormatServers(args []string) error
-	OpenvpnConfig(logger cli.OpenvpnConfigLogger, source cli.Source, ipv6Checker cli.IPv6Checker) error
-	HealthCheck(ctx context.Context, source cli.Source, warner cli.Warner) error
+	OpenvpnConfig(logger cli.OpenvpnConfigLogger, source sources.Source) error
+	HealthCheck(ctx context.Context, source sources.Source, warner cli.Warner) error
 	Update(ctx context.Context, args []string, logger cli.UpdaterLogger) error
 }

@@ -569,9 +538,3 @@ 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
-}
--- a/go.mod
+++ b/go.mod
@@ -1,51 +1,45 @@
 module github.com/qdm12/gluetun

-go 1.20
+go 1.17

 require (
-	github.com/breml/rootcerts v0.2.11
-	github.com/fatih/color v1.15.0
+	github.com/breml/rootcerts v0.2.6
+	github.com/fatih/color v1.13.0
 	github.com/golang/mock v1.6.0
 	github.com/qdm12/dns v1.11.0
 	github.com/qdm12/golibs v0.0.0-20210822203818-5c568b0777b6
-	github.com/qdm12/gosettings v0.3.0-rc13
 	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 v0.2.0-rc1
+	github.com/qdm12/govalid v0.1.0
 	github.com/qdm12/log v0.1.0
-	github.com/qdm12/ss-server v0.5.0-rc1
+	github.com/qdm12/ss-server v0.4.0
 	github.com/qdm12/updated v0.0.0-20210603204757-205acfe6937e
-	github.com/stretchr/testify v1.8.4
-	github.com/vishvananda/netlink v1.2.1-beta.2
-	github.com/youmark/pkcs8 v0.0.0-20201027041543-1326539a0a0a
-	golang.org/x/net v0.10.0
-	golang.org/x/sys v0.8.0
-	golang.org/x/text v0.10.0
-	golang.zx2c4.com/wireguard v0.0.0-20230325221338-052af4a8072b
-	golang.zx2c4.com/wireguard/wgctrl v0.0.0-20230215201556-9c5414ab4bde
-	inet.af/netaddr v0.0.0-20220811202034-502d2d690317
+	github.com/stretchr/testify v1.8.0
+	github.com/vishvananda/netlink v1.1.1-0.20211129163951-9ada19101fc5
+	golang.org/x/net v0.0.0-20210916014120-12bc252f5db8
+	golang.org/x/sys v0.0.0-20210630005230-0f9fa26af87c
+	golang.org/x/text v0.3.7
+	golang.zx2c4.com/wireguard v0.0.0-20210805125648-3957e9b9dd19
+	golang.zx2c4.com/wireguard/wgctrl v0.0.0-20210803171230-4253848d036c
+	inet.af/netaddr v0.0.0-20210718074554-06ca8145d722
 )

 require (
 	github.com/davecgh/go-spew v1.1.1 // indirect
-	github.com/google/go-cmp v0.5.9 // indirect
-	github.com/josharian/native v1.0.0 // indirect
-	github.com/mattn/go-colorable v0.1.13 // indirect
-	github.com/mattn/go-isatty v0.0.17 // 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/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/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 v0.0.0-20211027215823-ae77deb06f29 // indirect
-	go4.org/unsafe/assume-no-moving-gc v0.0.0-20230221090011-e4bae7ad2296 // indirect
-	golang.org/x/crypto v0.9.0 // 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
+	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
 	gopkg.in/yaml.v3 v3.0.1 // indirect
 )
--- a/go.sum
+++ b/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 v0.2.11 h1:njUAtoyZ6HUXPAPk63tGz0BEZk1/6gyfqK5fTzksHkM=
-github.com/breml/rootcerts v0.2.11/go.mod h1:S/PKh+4d1HUn4HQovEB8hPJZO6pUZYrIhmXBhsegfXw=
+github.com/breml/rootcerts v0.2.6 h1:CdPczjzItec+wopLoDsBAFcLEai2q7Yayfg/94/q/2E=
+github.com/breml/rootcerts v0.2.6/go.mod h1:24FDtzYMpqIeYC7QzaE8VPRQaFZU5TIUDlyk8qwjD88=
 github.com/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 v1.15.0 h1:kOqh6YHBtK8aywxGerMG2Eq3H6Qgoqeo13Bk2Mv/nBs=
-github.com/fatih/color v1.15.0/go.mod h1:0h5ZqXfHYED7Bhv2ZJamyIOUej9KtShiJESRwBDUSsw=
+github.com/fatih/color v1.13.0 h1:8LOYc1KYPPmyKMuN8QV2DNRWNbLo6LZ0iLs8+mlH53w=
+github.com/fatih/color v1.13.0/go.mod h1:kLAiJbzzSOZDVNGyDpeOxJ47H46qBXwg5ILebYFFOfk=
 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=
@@ -36,18 +36,28 @@ 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/btree v1.0.1 h1:gK4Kx5IaGY9CD5sPJ36FHiBJ6ZXl0kilRiiCj+jdYp4=
+github.com/google/go-cmp v0.2.0/go.mod h1:oXzfMopK8JAjlY9xF4vHSVASa0yLyX7SntLO5aqRK0M=
 github.com/google/go-cmp v0.3.0/go.mod h1:8QqcDgzrUqlUb/G2PQTWiueGozuR1884gddMywk6iLU=
-github.com/google/go-cmp v0.5.6/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/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/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 v1.0.0 h1:Ts/E8zCSEsG17dUqv7joXJFybuMLjQfWE04tsBODTxk=
-github.com/josharian/native v1.0.0/go.mod h1:7X/raswPFr05uY3HiLlYeyQntB6OO7E/d2Cu7qoaN2w=
+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/kevinburke/ssh_config v0.0.0-20190725054713-01f96b0aa0cd/go.mod h1:CT57kijsi8u/K/BOFA39wgDQJ9CxiF4nAY/ojJ6r6mM=
 github.com/kr/pretty v0.1.0 h1:L/CwN0zerZDmRFUapSPitk6f+Q3+0za1rQkzVuMiMFI=
 github.com/kr/pretty v0.1.0/go.mod h1:dAy3ld7l9f0ibDNOQOHHMYYIIbhfbHSm3C4ZsoJORNo=
@@ -58,23 +68,29 @@ 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 v0.1.13 h1:fFA4WZxdEF4tXPZVKMLwD8oUnCTTo08duU7wxecdEvA=
-github.com/mattn/go-colorable v0.1.13/go.mod h1:7S9/ev0klgBDR4GtXTXX8a3vIGJpMovkB8vQcUbaXHg=
+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-isatty v0.0.12/go.mod h1:cbi8OIDigv2wuxKPP5vlRcQ1OAZbq2CE4Kysco4FUpU=
-github.com/mattn/go-isatty v0.0.16/go.mod h1:kYGgaQfpe5nmfYZH+SKPsOc2e4SrIfOl2e/yFXSvRLM=
-github.com/mattn/go-isatty v0.0.17 h1:BTarxUcIeDqL27Mc+vyvdWYSL28zpIhv3RoTdsLMPng=
-github.com/mattn/go-isatty v0.0.17/go.mod h1:kYGgaQfpe5nmfYZH+SKPsOc2e4SrIfOl2e/yFXSvRLM=
-github.com/mdlayher/genetlink v1.2.0 h1:4yrIkRV5Wfk1WfpWTcoOlGmsWgQj3OtQN9ZsbrE+XtU=
-github.com/mdlayher/genetlink v1.2.0/go.mod h1:ra5LDov2KrUCZJiAtEvXXZBxGMInICMXIwshlJ+qRxQ=
-github.com/mdlayher/netlink v1.6.0/go.mod h1:0o3PlBmGst1xve7wQ7j/hwpNaFaH4qCRyWCdcZk8/vA=
-github.com/mdlayher/netlink v1.6.2 h1:D2zGSkvYsJ6NreeED3JiVTu1lj2sIYATqSaZlhPzUgQ=
-github.com/mdlayher/netlink v1.6.2/go.mod h1:O1HXX2sIWSMJ3Qn1BYZk1yZM+7iMki/uYGGiwGyq/iU=
-github.com/mdlayher/socket v0.1.1/go.mod h1:mYV5YIZAfHh4dzDVzI8x8tWLWCliuX8Mon5Awbj+qDs=
-github.com/mdlayher/socket v0.2.3 h1:XZA2X2TjdOwNoNPVPclRCURoX/hokBY8nkTmRZFEheM=
-github.com/mdlayher/socket v0.2.3/go.mod h1:bz12/FozYNH/VbvC3q7TRIK/Y6dH1kCKsXaUeXi/FmY=
+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=
+github.com/mdlayher/netlink v1.4.0 h1:n3ARR+Fm0dDv37dj5wSWZXDKcy+U0zwcXS3zKMnSiT0=
+github.com/mdlayher/netlink v1.4.0/go.mod h1:dRJi5IABcZpBD2A3D0Mv/AiX8I9uDEu5oGkAVrekmf8=
 github.com/miekg/dns v1.1.40 h1:pyyPFfGMnciYUk/mXpKkVmeMQjfXqt3FAJ2hy7tPiLA=
 github.com/miekg/dns v1.1.40/go.mod h1:KNUDUusw/aVsxyTYZM1oqvCicbwhgbNgztCETuNZ7xM=
 github.com/mikioh/ipaddr v0.0.0-20190404000644-d465c8ab6721 h1:RlZweED6sbSArvlE924+mUcZuXKLBHA35U7LN621Bws=
+github.com/mikioh/ipaddr v0.0.0-20190404000644-d465c8ab6721/go.mod h1:Ickgr2WtCLZ2MDGd4Gr0geeCH5HybhRJbonOgQpvSxc=
 github.com/mitchellh/go-homedir v1.1.0/go.mod h1:SfyaCUpYCn1Vlf4IUYiD9fPX4A5wJrkLzIz1N1q0pr0=
 github.com/mitchellh/mapstructure v1.1.2/go.mod h1:FVVH3fgwuzCH5S8UJGiWEs2h04kUh9fWfEaFds41c1Y=
 github.com/mr-tron/base58 v1.2.0 h1:T/HDJBh4ZCPbU39/+c3rRvE0uKBQlU27+QI8LJ4t64o=
@@ -91,20 +107,18 @@ github.com/qdm12/golibs v0.0.0-20210603202746-e5494e9c2ebb/go.mod h1:15RBzkun0i8
 github.com/qdm12/golibs v0.0.0-20210723175634-a75ca7fd74c2/go.mod h1:6aRbg4Z/bTbm9JfxsGXfWKHi7zsOvPfUTK1S5HuAFKg=
 github.com/qdm12/golibs v0.0.0-20210822203818-5c568b0777b6 h1:bge5AL7cjHJMPz+5IOz5yF01q/l8No6+lIEBieA8gMg=
 github.com/qdm12/golibs v0.0.0-20210822203818-5c568b0777b6/go.mod h1:6aRbg4Z/bTbm9JfxsGXfWKHi7zsOvPfUTK1S5HuAFKg=
-github.com/qdm12/gosettings v0.3.0-rc13 h1:fag+/hFPBUcNk3a5ifUbwNS2VgXFpxindkl8mQNk76U=
-github.com/qdm12/gosettings v0.3.0-rc13/go.mod h1:JRV3opOpHvnKlIA29lKQMdYw1WSMVMfHYLLHPHol5ME=
 github.com/qdm12/goshutdown v0.3.0 h1:pqBpJkdwlZlfTEx4QHtS8u8CXx6pG0fVo6S1N0MpSEM=
 github.com/qdm12/goshutdown v0.3.0/go.mod h1:EqZ46No00kCTZ5qzdd3qIzY6ayhMt24QI8Mh8LVQYmM=
 github.com/qdm12/gosplash v0.1.0 h1:Sfl+zIjFZFP7b0iqf2l5UkmEY97XBnaKkH3FNY6Gf7g=
 github.com/qdm12/gosplash v0.1.0/go.mod h1:+A3fWW4/rUeDXhY3ieBzwghKdnIPFJgD8K3qQkenJlw=
 github.com/qdm12/gotree v0.2.0 h1:+58ltxkNLUyHtATFereAcOjBVfY6ETqRex8XK90Fb/c=
 github.com/qdm12/gotree v0.2.0/go.mod h1:1SdFaqKZuI46U1apbXIf25pDMNnrPuYLEqMF/qL4lY4=
-github.com/qdm12/govalid v0.2.0-rc1 h1:4iYQvU4ibrASgzelsEgZX4JyKX3UTB/DcHObzQ7BXtw=
-github.com/qdm12/govalid v0.2.0-rc1/go.mod h1:/uWzVWMuS71wmbsVnlUxpQiy6EAXqm8eQ2RbyA72roQ=
+github.com/qdm12/govalid v0.1.0 h1:UIFVmuaAg0Q+h0GeyfcFEZ5sQ5KJPvRQwycC1/cqDN8=
+github.com/qdm12/govalid v0.1.0/go.mod h1:CyS/OEQdOvunBgrtIsW93fjd4jBkwZPBjGSpxq3NwA4=
 github.com/qdm12/log v0.1.0 h1:jYBd/xscHYpblzZAd2kjZp2YmuYHjAAfbTViJWxoPTw=
 github.com/qdm12/log v0.1.0/go.mod h1:Vchi5M8uBvHfPNIblN4mjXn/oSbiWguQIbsgF1zdQPI=
-github.com/qdm12/ss-server v0.5.0-rc1 h1:2rJEhDnUUc9AKtvyVu+CrnJwvdEjMaB1zFRQvTUlDPw=
-github.com/qdm12/ss-server v0.5.0-rc1/go.mod h1:IoFYGpVpxfIB/dMTr0PnSegdhV1gEfZLS9Tr1Qn8uRg=
+github.com/qdm12/ss-server v0.4.0 h1:lMMYfDGc9P86Lyvd3+p8lK4hhgHUKDzjZC91FqJYkDU=
+github.com/qdm12/ss-server v0.4.0/go.mod h1:AY0p4huvPUPW+/CiWsJcDgT6sneDryk26VXSccPNCxY=
 github.com/qdm12/updated v0.0.0-20210603204757-205acfe6937e h1:4q+uFLawkaQRq3yARYLsjJPZd2wYwxn4g6G/5v0xW1g=
 github.com/qdm12/updated v0.0.0-20210603204757-205acfe6937e/go.mod h1:UvJRGkZ9XL3/D7e7JiTTVLm1F3Cymd3/gFpD6frEpBo=
 github.com/riobard/go-bloom v0.0.0-20200614022211-cdc8013cb5b3 h1:f/FNXud6gA3MNr8meMVVGxhp+QBTqY91tM8HjEuMjGg=
@@ -113,100 +127,107 @@ github.com/sergi/go-diff v1.0.0/go.mod h1:0CfEIISq7TuYL3j771MWULgwwjU+GofnZX9QAm
 github.com/src-d/gcfg v1.4.0/go.mod h1:p/UMsR43ujA89BJY9duynAwIpvqEujIH/jFlfL7jWoI=
 github.com/stretchr/objx v0.1.0/go.mod h1:HFkY916IF+rwdDfMAkV7OtwuqBVzrE8GR6GFx+wExME=
 github.com/stretchr/objx v0.2.0/go.mod h1:qt09Ya8vawLte6SNmTgCsAVtYtaKzEcn8ATUoHMkEqE=
+github.com/stretchr/objx v0.4.0/go.mod h1:YvHI0jy2hoMjB+UWwv71VJQ9isScKT/TqJzVSSt89Yw=
 github.com/stretchr/testify v1.2.2/go.mod h1:a8OnRcib4nhh0OaRAV+Yts87kKdq0PP7pXfy6kDkUVs=
 github.com/stretchr/testify v1.3.0/go.mod h1:M5WIy9Dh21IEIfnGCwXGc5bZfKNJtfHm1UVUgZn+9EI=
 github.com/stretchr/testify v1.4.0/go.mod h1:j7eGeouHqKxXV5pUuKE4zz7dFj8WfuZ+81PSLYec5m4=
 github.com/stretchr/testify v1.7.0/go.mod h1:6Fq8oRcR53rry900zMqJjRRixrwX3KX962/h/Wwjteg=
-github.com/stretchr/testify v1.8.4 h1:CcVxjf3Q8PM0mHUKJCdn+eZZtm5yQwehR5yeSVQQcUk=
-github.com/stretchr/testify v1.8.4/go.mod h1:sz/lmYIOXD/1dqDmKjjqLyZ2RngseejIcXlSw2iwfAo=
-github.com/vishvananda/netlink v1.2.1-beta.2 h1:Llsql0lnQEbHj0I1OuKyp8otXp0r3q0mPkuhwHfStVs=
-github.com/vishvananda/netlink v1.2.1-beta.2/go.mod h1:twkDnbuQxJYemMlGd4JFIcuhgX83tXhKS2B/PRMpOho=
+github.com/stretchr/testify v1.7.1/go.mod h1:6Fq8oRcR53rry900zMqJjRRixrwX3KX962/h/Wwjteg=
+github.com/stretchr/testify v1.8.0 h1:pSgiaMZlXftHpm5L7V1+rVB+AZJydKsMxsQBIJw4PKk=
+github.com/stretchr/testify v1.8.0/go.mod h1:yNjHg4UonilssWZ8iaSj1OCr/vHnekPRkoO+kdMU+MU=
+github.com/vishvananda/netlink v1.1.1-0.20211129163951-9ada19101fc5 h1:b/k/BVWzWRS5v6AB0gf2ckFSbFsHN5jR0HoNso1pN+w=
+github.com/vishvananda/netlink v1.1.1-0.20211129163951-9ada19101fc5/go.mod h1:twkDnbuQxJYemMlGd4JFIcuhgX83tXhKS2B/PRMpOho=
 github.com/vishvananda/netns v0.0.0-20200728191858-db3c7e526aae h1:4hwBBUfQCFe3Cym0ZtKyq7L16eZUtYKs+BaHDN6mAns=
 github.com/vishvananda/netns v0.0.0-20200728191858-db3c7e526aae/go.mod h1:DD4vA1DwXk04H54A1oHXtwZmA0grkVMdPxx/VGLCah0=
 github.com/xanzy/ssh-agent v0.2.1/go.mod h1:mLlQY/MoOhWBj+gOGMQkOeiEvkx+8pJSI+0Bx9h2kr4=
 github.com/yl2chen/cidranger v1.0.2/go.mod h1:9U1yz7WPYDwf0vpNWFaeRh0bjwz5RVgRy/9UEQfHl0g=
-github.com/youmark/pkcs8 v0.0.0-20201027041543-1326539a0a0a h1:fZHgsYlfvtyqToslyjUt3VOPF4J7aK/3MPcK7xp3PDk=
-github.com/youmark/pkcs8 v0.0.0-20201027041543-1326539a0a0a/go.mod h1:ul22v+Nro/R083muKhosV54bj5niojjWZvU8xrevuH4=
 github.com/yuin/goldmark v1.2.1/go.mod h1:3hX8gzYuyVAZsxl0MRgGTJEmQBFcNTphYh9decYSb74=
 github.com/yuin/goldmark v1.3.5/go.mod h1:mwnBkeHKe2W/ZEtQ+71ViKU8L12m81fl3OWwC1Zlc8k=
+go4.org/intern v0.0.0-20210108033219-3eb7198706b2 h1:VFTf+jjIgsldaz/Mr00VaCSswHJrI2hIjQygE/W4IMg=
 go4.org/intern v0.0.0-20210108033219-3eb7198706b2/go.mod h1:vLqJ+12kCw61iCWsPto0EOHhBS+o4rO5VIucbc9g2Cc=
-go4.org/intern v0.0.0-20211027215823-ae77deb06f29 h1:UXLjNohABv4S58tHmeuIZDO6e3mHpW2Dx33gaNt03LE=
-go4.org/intern v0.0.0-20211027215823-ae77deb06f29/go.mod h1:cS2ma+47FKrLPdXFpr7CuxiTW3eyJbWew4qx0qtQWDA=
 go4.org/unsafe/assume-no-moving-gc v0.0.0-20201222175341-b30ae309168e/go.mod h1:FftLjUGFEDu5k8lt0ddY+HcrH/qU/0qk+H8j9/nTl3E=
 go4.org/unsafe/assume-no-moving-gc v0.0.0-20201222180813-1025295fd063/go.mod h1:FftLjUGFEDu5k8lt0ddY+HcrH/qU/0qk+H8j9/nTl3E=
-go4.org/unsafe/assume-no-moving-gc v0.0.0-20211027215541-db492cf91b37/go.mod h1:FftLjUGFEDu5k8lt0ddY+HcrH/qU/0qk+H8j9/nTl3E=
+go4.org/unsafe/assume-no-moving-gc v0.0.0-20220617031537-928513b29760 h1:FyBZqvoA/jbNzuAWLQE2kG820zMAkcilx6BMjGbL/E4=
 go4.org/unsafe/assume-no-moving-gc v0.0.0-20220617031537-928513b29760/go.mod h1:FftLjUGFEDu5k8lt0ddY+HcrH/qU/0qk+H8j9/nTl3E=
-go4.org/unsafe/assume-no-moving-gc v0.0.0-20230221090011-e4bae7ad2296 h1:QJ/xcIANMLApehfgPCHnfK1hZiaMmbaTVmPv7DAoTbo=
-go4.org/unsafe/assume-no-moving-gc v0.0.0-20230221090011-e4bae7ad2296/go.mod h1:FftLjUGFEDu5k8lt0ddY+HcrH/qU/0qk+H8j9/nTl3E=
 golang.org/x/crypto v0.0.0-20190219172222-a4c6cb3142f2/go.mod h1:6SG95UA2DQfeDnfUPMdvaQW0Q7yPrPDi9nlGo2tz2b4=
 golang.org/x/crypto v0.0.0-20190308221718-c2843e01d9a2/go.mod h1:djNgcEr1/C05ACkg1iLfiJU5Ep61QUkGW8qpdssI0+w=
 golang.org/x/crypto v0.0.0-20190701094942-4def268fd1a4/go.mod h1:yigFU9vqHzYiE8UmvKecakEJjdnWj3jj499lnFckfCI=
 golang.org/x/crypto v0.0.0-20191011191535-87dc89f01550/go.mod h1:yigFU9vqHzYiE8UmvKecakEJjdnWj3jj499lnFckfCI=
-golang.org/x/crypto v0.0.0-20200302210943-78000ba7a073/go.mod h1:LzIPMQfyMNhhGPhUkYOs5KpL4U8rLKemX1yGLhDgUto=
 golang.org/x/crypto v0.0.0-20200622213623-75b288015ac9/go.mod h1:LzIPMQfyMNhhGPhUkYOs5KpL4U8rLKemX1yGLhDgUto=
+golang.org/x/crypto v0.0.0-20210220033148-5ea612d1eb83/go.mod h1:jdWPYTVW3xRLrWPugEBEK3UY2ZEsg3UU495nc5E+M+I=
+golang.org/x/crypto v0.0.0-20210503195802-e9a32991a82e/go.mod h1:P+XmwS30IXTQdn5tA2iutPOUgjI07+tq3H3K9MVA1s8=
 golang.org/x/crypto v0.0.0-20210513164829-c07d793c2f9a/go.mod h1:P+XmwS30IXTQdn5tA2iutPOUgjI07+tq3H3K9MVA1s8=
+golang.org/x/crypto v0.0.0-20210711020723-a769d52b0f97 h1:/UOmuWzQfxxo9UtlXMwuQU8CMgg1eZXqTRwkSQJWKOI=
 golang.org/x/crypto v0.0.0-20210711020723-a769d52b0f97/go.mod h1:GvvjBRRGRdwPK5ydBHafDWAxML/pGHZbMvKqRZ5+Abc=
-golang.org/x/crypto v0.9.0 h1:LF6fAI+IutBocDJ2OT0Q1g8plpYljMZ4+lty+dsqw3g=
-golang.org/x/crypto v0.9.0/go.mod h1:yrmDGqONDYtNj3tH8X9dzUun2m2lzPa9ngI6/RUPGR0=
-golang.org/x/exp v0.0.0-20230522175609-2e198f4a06a1 h1:k/i9J1pBpvlfR+9QsetwPyERsqu1GIbi967PQMq3Ivc=
-golang.org/x/exp v0.0.0-20230522175609-2e198f4a06a1/go.mod h1:V1LtkGg67GoY2N1AnLN78QLrzxkLyJw7RJb1gzOOz9w=
 golang.org/x/mod v0.1.1-0.20191105210325-c90efee705ee/go.mod h1:QqPTAvyqsEbceGzBzNggFXnrqF1CaUcvgkdR5Ot7KZg=
 golang.org/x/mod v0.3.0/go.mod h1:s0Qsj1ACt9ePp/hMypM3fl4fZqREWJwdYDEqhRiZZUA=
 golang.org/x/mod v0.4.2/go.mod h1:s0Qsj1ACt9ePp/hMypM3fl4fZqREWJwdYDEqhRiZZUA=
 golang.org/x/net v0.0.0-20181005035420-146acd28ed58/go.mod h1:mL1N/T3taQHkDXs73rZJwtUhF3w3ftmwwsq0BUmARs4=
+golang.org/x/net v0.0.0-20190311183353-d8887717615a/go.mod h1:t9HGtf8HONx5eT2rtn7q6eTqICYqUVnKs3thJo3Qplg=
 golang.org/x/net v0.0.0-20190404232315-eb5bcb51f2a3/go.mod h1:t9HGtf8HONx5eT2rtn7q6eTqICYqUVnKs3thJo3Qplg=
-golang.org/x/net v0.0.0-20190503192946-f4e77d36d62c/go.mod h1:t9HGtf8HONx5eT2rtn7q6eTqICYqUVnKs3thJo3Qplg=
 golang.org/x/net v0.0.0-20190620200207-3b0461eec859/go.mod h1:z5CRVTTTmAJ677TzLLGU+0bjPO0LkuOLi4/5GtJWs/s=
 golang.org/x/net v0.0.0-20190724013045-ca1201d0de80/go.mod h1:z5CRVTTTmAJ677TzLLGU+0bjPO0LkuOLi4/5GtJWs/s=
+golang.org/x/net v0.0.0-20190827160401-ba9fcec4b297/go.mod h1:z5CRVTTTmAJ677TzLLGU+0bjPO0LkuOLi4/5GtJWs/s=
 golang.org/x/net v0.0.0-20190923162816-aa69164e4478/go.mod h1:z5CRVTTTmAJ677TzLLGU+0bjPO0LkuOLi4/5GtJWs/s=
+golang.org/x/net v0.0.0-20191007182048-72f939374954/go.mod h1:z5CRVTTTmAJ677TzLLGU+0bjPO0LkuOLi4/5GtJWs/s=
+golang.org/x/net v0.0.0-20200202094626-16171245cfb2/go.mod h1:z5CRVTTTmAJ677TzLLGU+0bjPO0LkuOLi4/5GtJWs/s=
+golang.org/x/net v0.0.0-20201010224723-4f7140c49acb/go.mod h1:sp8m0HH+o8qH0wwXwYZr8TS3Oi6o0r6Gce1SSxlDquU=
 golang.org/x/net v0.0.0-20201021035429-f5854403a974/go.mod h1:sp8m0HH+o8qH0wwXwYZr8TS3Oi6o0r6Gce1SSxlDquU=
+golang.org/x/net v0.0.0-20201110031124-69a78807bb2b/go.mod h1:sp8m0HH+o8qH0wwXwYZr8TS3Oi6o0r6Gce1SSxlDquU=
+golang.org/x/net v0.0.0-20201216054612-986b41b23924/go.mod h1:m0MpNAwzfU5UDzcl9v0D8zg8gWTRqZa9RBIspLL5mdg=
+golang.org/x/net v0.0.0-20201224014010-6772e930b67b/go.mod h1:m0MpNAwzfU5UDzcl9v0D8zg8gWTRqZa9RBIspLL5mdg=
+golang.org/x/net v0.0.0-20210119194325-5f4716e94777/go.mod h1:m0MpNAwzfU5UDzcl9v0D8zg8gWTRqZa9RBIspLL5mdg=
 golang.org/x/net v0.0.0-20210226172049-e18ecbb05110/go.mod h1:m0MpNAwzfU5UDzcl9v0D8zg8gWTRqZa9RBIspLL5mdg=
 golang.org/x/net v0.0.0-20210405180319-a5a99cb37ef4/go.mod h1:p54w0d4576C0XHj96bSt6lcn1PtDYWL6XObtHCRCNQM=
-golang.org/x/net v0.0.0-20210928044308-7d9f5e0b762b/go.mod h1:9nx3DQGgdP8bBQD5qxJ1jj9UTztislL4KSBs9R2vV5Y=
-golang.org/x/net v0.0.0-20220127200216-cd36cc0744dd/go.mod h1:CfG3xpIq0wQ8r1q4Su4UZFWDARRcnwPjda9FqA0JpMk=
-golang.org/x/net v0.0.0-20220923203811-8be639271d50/go.mod h1:YDH+HFinaLZZlnHAfSS6ZXJJ9M9t4Dl22yv3iI2vPwk=
-golang.org/x/net v0.10.0 h1:X2//UzNDwYmtCLn7To6G58Wr6f5ahEAQgKNzv9Y951M=
-golang.org/x/net v0.10.0/go.mod h1:0qNGK6F8kojg2nk9dLZ2mShWaEBan6FAoqfSigmmuDg=
+golang.org/x/net v0.0.0-20210504132125-bbd867fde50d/go.mod h1:9nx3DQGgdP8bBQD5qxJ1jj9UTztislL4KSBs9R2vV5Y=
+golang.org/x/net v0.0.0-20210916014120-12bc252f5db8 h1:/6y1LfuqNuQdHAm0jjtPtgRcxIxjVZgm5OTu8/QhZvk=
+golang.org/x/net v0.0.0-20210916014120-12bc252f5db8/go.mod h1:9nx3DQGgdP8bBQD5qxJ1jj9UTztislL4KSBs9R2vV5Y=
 golang.org/x/sync v0.0.0-20190423024810-112230192c58/go.mod h1:RxMgew5VJxzue5/jJTE5uejpjVlOe/izrB70Jof72aM=
 golang.org/x/sync v0.0.0-20201020160332-67f06af15bc9/go.mod h1:RxMgew5VJxzue5/jJTE5uejpjVlOe/izrB70Jof72aM=
+golang.org/x/sync v0.0.0-20210220032951-036812b2e83c h1:5KslGYwFpkhGh+Q16bwMP3cOontH8FOep7tGV86Y7SQ=
 golang.org/x/sync v0.0.0-20210220032951-036812b2e83c/go.mod h1:RxMgew5VJxzue5/jJTE5uejpjVlOe/izrB70Jof72aM=
-golang.org/x/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 v0.0.0-20210927094055-39ccf1dd6fa6/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 v0.8.0 h1:EBmGv8NaZBZTWvrbjNoL6HVt+IVy3QDQpJs7VRIw3tU=
-golang.org/x/sys v0.8.0/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/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 v0.10.0 h1:UpjohKhiEgNc0CSauXmwYftY1+LlaC75SJwh0SgCX58=
-golang.org/x/text v0.10.0/go.mod h1:TvPlkZtksWOMsz7fbANvkp4WM8x/WCo/om8BMLbz+aE=
-golang.org/x/time v0.0.0-20191024005414-555d28b269f0 h1:/5xXl8Y5W96D+TtHSlonuFqGHIWVuyCkGJLwGh9JJFs=
 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=
@@ -216,13 +237,13 @@ 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/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=
+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=
 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=
@@ -235,7 +256,6 @@ 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=
 inet.af/netaddr v0.0.0-20210511181906-37180328850c/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=
+inet.af/netaddr v0.0.0-20210718074554-06ca8145d722 h1:Qws2rZnQudC58cIagVucPQDLmMi3kAXgxscsgD0v6DU=
+inet.af/netaddr v0.0.0-20210718074554-06ca8145d722/go.mod h1:z0nx+Dh+7N7CC8V5ayHtHGpZpxLQZZxkIaaz6HN65Ls=
--- a/internal/alpine/version.go
+++ b/internal/alpine/version.go
@@ -7,7 +7,7 @@ import (
 	"strings"
 )

-func (a *Alpine) Version(context.Context) (version string, err error) {
+func (a *Alpine) Version(ctx context.Context) (version string, err error) {
 	file, err := os.OpenFile(a.alpineReleasePath, os.O_RDONLY, 0)
 	if err != nil {
 		return "", err
--- a/internal/cli/ci.go
+++ b/internal/cli/ci.go
@@ -2,6 +2,6 @@ package cli

 import "context"

-func (c *CLI) CI(context.Context) error {
+func (c *CLI) CI(context context.Context) error {
 	return nil
 }
--- a/internal/cli/formatservers.go
+++ b/internal/cli/formatservers.go
@@ -61,7 +61,7 @@ func (c *CLI) FormatServers(args []string) error {
 	}
 	switch len(providers) {
 	case 0:
-		return fmt.Errorf("%w", ErrProviderUnspecified)
+		return ErrProviderUnspecified
 	case 1:
 	default:
 		return fmt.Errorf("%w: %d specified: %s",
@@ -73,7 +73,7 @@ func (c *CLI) FormatServers(args []string) error {
 	logger := newNoopLogger()
 	storage, err := storage.New(logger, constants.ServersData)
 	if err != nil {
-		return fmt.Errorf("creating servers storage: %w", err)
+		return fmt.Errorf("cannot create servers storage: %w", err)
 	}

 	formatted := storage.FormatToMarkdown(providerToFormat)
@@ -81,18 +81,18 @@ func (c *CLI) FormatServers(args []string) error {
 	output = filepath.Clean(output)
 	file, err := os.OpenFile(output, os.O_TRUNC|os.O_WRONLY|os.O_CREATE, 0644)
 	if err != nil {
-		return fmt.Errorf("opening output file: %w", err)
+		return fmt.Errorf("cannot open output file: %w", err)
 	}

 	_, err = fmt.Fprint(file, formatted)
 	if err != nil {
 		_ = file.Close()
-		return fmt.Errorf("writing to output file: %w", err)
+		return fmt.Errorf("cannot write to output file: %w", err)
 	}

 	err = file.Close()
 	if err != nil {
-		return fmt.Errorf("closing output file: %w", err)
+		return fmt.Errorf("cannot close output file: %w", err)
 	}

 	return nil
--- a/internal/cli/healthcheck.go
+++ b/internal/cli/healthcheck.go
@@ -6,18 +6,17 @@ 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 Source, _ Warner) error {
+func (c *CLI) HealthCheck(ctx context.Context, source sources.Source, warner Warner) error {
 	// Extract the health server port from the configuration.
 	config, err := source.ReadHealth()
 	if err != nil {
 		return err
 	}

-	config.SetDefaults()
-
 	err = config.Validate()
 	if err != nil {
 		return err
--- a/internal/cli/nooplogger.go
+++ b/internal/cli/nooplogger.go
@@ -8,9 +8,9 @@ func newNoopLogger() *noopLogger {
 	return new(noopLogger)
 }

-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)       {}
+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)      {}
--- a/internal/cli/openvpnconfig.go
+++ b/internal/cli/openvpnconfig.go
@@ -3,11 +3,12 @@ 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/openvpn/extract"
 	"github.com/qdm12/gluetun/internal/provider"
@@ -28,19 +29,14 @@ type Unzipper interface {

 type ParallelResolver interface {
 	Resolve(ctx context.Context, settings resolver.ParallelSettings) (
-		hostToIPs map[string][]netip.Addr, warnings []string, err error)
+		hostToIPs map[string][]net.IP, warnings []string, err error)
 }

 type IPFetcher interface {
-	FetchMultiInfo(ctx context.Context, ips []netip.Addr) (data []ipinfo.Response, err error)
+	FetchMultiInfo(ctx context.Context, ips []net.IP) (data []ipinfo.Response, err error)
 }

-type IPv6Checker interface {
-	IsIPv6Supported() (supported bool, err error)
-}
-
-func (c *CLI) OpenvpnConfig(logger OpenvpnConfigLogger, source Source,
-	ipv6Checker IPv6Checker) error {
+func (c *CLI) OpenvpnConfig(logger OpenvpnConfigLogger, source sources.Source) error {
 	storage, err := storage.New(logger, constants.ServersData)
 	if err != nil {
 		return err
@@ -51,13 +47,8 @@ func (c *CLI) OpenvpnConfig(logger OpenvpnConfigLogger, source Source,
 		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)
+	if err = allSettings.Validate(storage); err != nil {
+		return err
 	}

 	// Unused by this CLI command
@@ -71,14 +62,12 @@ func (c *CLI) OpenvpnConfig(logger OpenvpnConfigLogger, source Source,
 	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, ipv6Supported)
+	connection, err := providerConf.GetConnection(allSettings.VPN.Provider.ServerSelection)
 	if err != nil {
 		return err
 	}

-	lines := providerConf.OpenVPNConfig(connection,
-		allSettings.VPN.OpenVPN, ipv6Supported)
+	lines := providerConf.OpenVPNConfig(connection, allSettings.VPN.OpenVPN)

 	fmt.Println(strings.Join(lines, "\n"))
 	return nil
--- a/internal/cli/update.go
+++ b/internal/cli/update.go
@@ -51,14 +51,14 @@ func (c *CLI) Update(ctx context.Context, args []string, logger UpdaterLogger) e
 	}

 	if !endUserMode && !maintainerMode {
-		return fmt.Errorf("%w", ErrModeUnspecified)
+		return ErrModeUnspecified
 	}

 	if updateAll {
 		options.Providers = providers.All()
 	} else {
 		if csvProviders == "" {
-			return fmt.Errorf("%w", ErrNoProviderSpecified)
+			return ErrNoProviderSpecified
 		}
 		options.Providers = strings.Split(csvProviders, ",")
 	}
@@ -72,7 +72,7 @@ func (c *CLI) Update(ctx context.Context, args []string, logger UpdaterLogger) e

 	storage, err := storage.New(logger, constants.ServersData)
 	if err != nil {
-		return fmt.Errorf("creating servers storage: %w", err)
+		return fmt.Errorf("cannot create servers storage: %w", err)
 	}

 	const clientTimeout = 10 * time.Second
@@ -88,13 +88,13 @@ func (c *CLI) Update(ctx context.Context, args []string, logger UpdaterLogger) e
 	updater := updater.New(httpClient, storage, providers, logger)
 	err = updater.UpdateServers(ctx, options.Providers, options.MinRatio)
 	if err != nil {
-		return fmt.Errorf("updating server information: %w", err)
+		return fmt.Errorf("cannot update server information: %w", err)
 	}

 	if maintainerMode {
 		err := storage.FlushToFile(c.repoServersPath)
 		if err != nil {
-			return fmt.Errorf("writing servers data to embedded JSON file: %w", err)
+			return fmt.Errorf("cannot write servers data to embedded JSON file: %w", err)
 		}
 	}

--- a/internal/configuration/settings/dns.go
+++ b/internal/configuration/settings/dns.go
@@ -2,9 +2,9 @@ package settings

 import (
 	"fmt"
-	"net/netip"
+	"net"

-	"github.com/qdm12/gosettings"
+	"github.com/qdm12/gluetun/internal/configuration/settings/helpers"
 	"github.com/qdm12/gotree"
 )

@@ -13,9 +13,9 @@ 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 the zero value in the internal
+	// DoT server. It cannot be nil in the internal
 	// state.
-	ServerAddress netip.Addr
+	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
@@ -31,7 +31,7 @@ type DNS struct {
 func (d DNS) validate() (err error) {
 	err = d.DoT.validate()
 	if err != nil {
-		return fmt.Errorf("validating DoT settings: %w", err)
+		return fmt.Errorf("failed validating DoT settings: %w", err)
 	}

 	return nil
@@ -39,8 +39,8 @@ func (d DNS) validate() (err error) {

 func (d *DNS) Copy() (copied DNS) {
 	return DNS{
-		ServerAddress:  d.ServerAddress,
-		KeepNameserver: gosettings.CopyPointer(d.KeepNameserver),
+		ServerAddress:  helpers.CopyIP(d.ServerAddress),
+		KeepNameserver: helpers.CopyBoolPtr(d.KeepNameserver),
 		DoT:            d.DoT.copy(),
 	}
 }
@@ -48,8 +48,8 @@ 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 = gosettings.MergeWithValidator(d.ServerAddress, other.ServerAddress)
-	d.KeepNameserver = gosettings.MergeWithPointer(d.KeepNameserver, other.KeepNameserver)
+	d.ServerAddress = helpers.MergeWithIP(d.ServerAddress, other.ServerAddress)
+	d.KeepNameserver = helpers.MergeWithBool(d.KeepNameserver, other.KeepNameserver)
 	d.DoT.mergeWith(other.DoT)
 }

@@ -57,15 +57,15 @@ func (d *DNS) mergeWith(other DNS) {
 // settings object with any field set in the other
 // settings.
 func (d *DNS) overrideWith(other DNS) {
-	d.ServerAddress = gosettings.OverrideWithValidator(d.ServerAddress, other.ServerAddress)
-	d.KeepNameserver = gosettings.OverrideWithPointer(d.KeepNameserver, other.KeepNameserver)
+	d.ServerAddress = helpers.OverrideWithIP(d.ServerAddress, other.ServerAddress)
+	d.KeepNameserver = helpers.OverrideWithBool(d.KeepNameserver, other.KeepNameserver)
 	d.DoT.overrideWith(other.DoT)
 }

 func (d *DNS) setDefaults() {
-	localhost := netip.AddrFrom4([4]byte{127, 0, 0, 1})
-	d.ServerAddress = gosettings.DefaultValidator(d.ServerAddress, localhost)
-	d.KeepNameserver = gosettings.DefaultPointer(d.KeepNameserver, false)
+	localhost := net.IPv4(127, 0, 0, 1) //nolint:gomnd
+	d.ServerAddress = helpers.DefaultIP(d.ServerAddress, localhost)
+	d.KeepNameserver = helpers.DefaultBool(d.KeepNameserver, false)
 	d.DoT.setDefaults()
 }

@@ -76,7 +76,7 @@ func (d DNS) String() string {
 func (d DNS) toLinesNode() (node *gotree.Node) {
 	node = gotree.New("DNS settings:")
 	node.Appendf("DNS server address to use: %s", d.ServerAddress)
-	node.Appendf("Keep existing nameserver(s): %s", gosettings.BoolToYesNo(d.KeepNameserver))
+	node.Appendf("Keep existing nameserver(s): %s", helpers.BoolPtrToYesNo(d.KeepNameserver))
 	node.AppendNode(d.DoT.toLinesNode())
 	return node
 }
--- a/internal/configuration/settings/dnsblacklist.go
+++ b/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/gosettings"
+	"github.com/qdm12/gluetun/internal/configuration/settings/helpers"
 	"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        []netip.Addr
-	AddBlockedIPPrefixes []netip.Prefix
+	AddBlockedIPs        []netaddr.IP
+	AddBlockedIPPrefixes []netaddr.IPPrefix
 }

 func (b *DNSBlacklist) setDefaults() {
-	b.BlockMalicious = gosettings.DefaultPointer(b.BlockMalicious, true)
-	b.BlockAds = gosettings.DefaultPointer(b.BlockAds, false)
-	b.BlockSurveillance = gosettings.DefaultPointer(b.BlockSurveillance, true)
+	b.BlockMalicious = helpers.DefaultBool(b.BlockMalicious, true)
+	b.BlockAds = helpers.DefaultBool(b.BlockAds, false)
+	b.BlockSurveillance = helpers.DefaultBool(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:       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),
+		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),
 	}
 }

 func (b *DNSBlacklist) mergeWith(other DNSBlacklist) {
-	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)
+	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)
 }

 func (b *DNSBlacklist) overrideWith(other DNSBlacklist) {
-	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)
+	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)
 }

 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:        netipAddressesToNetaddrIPs(b.AddBlockedIPs),
-		AddBlockedIPPrefixes: netipPrefixesToNetaddrIPPrefixes(b.AddBlockedIPPrefixes),
+		AddBlockedIPs:        b.AddBlockedIPs,
+		AddBlockedIPPrefixes: 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", gosettings.BoolToYesNo(b.BlockMalicious))
-	node.Appendf("Block ads: %s", gosettings.BoolToYesNo(b.BlockAds))
-	node.Appendf("Block surveillance: %s", gosettings.BoolToYesNo(b.BlockSurveillance))
+	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))

 	if len(b.AllowedHosts) > 0 {
 		allowedHostsNode := node.Appendf("Allowed hosts:")
--- a/internal/configuration/settings/dot.go
+++ b/internal/configuration/settings/dot.go
@@ -5,7 +5,7 @@ import (
 	"fmt"
 	"time"

-	"github.com/qdm12/gosettings"
+	"github.com/qdm12/gluetun/internal/configuration/settings/helpers"
 	"github.com/qdm12/gotree"
 )

@@ -54,8 +54,8 @@ func (d DoT) validate() (err error) {

 func (d *DoT) copy() (copied DoT) {
 	return DoT{
-		Enabled:      gosettings.CopyPointer(d.Enabled),
-		UpdatePeriod: gosettings.CopyPointer(d.UpdatePeriod),
+		Enabled:      helpers.CopyBoolPtr(d.Enabled),
+		UpdatePeriod: helpers.CopyDurationPtr(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 = gosettings.MergeWithPointer(d.Enabled, other.Enabled)
-	d.UpdatePeriod = gosettings.MergeWithPointer(d.UpdatePeriod, other.UpdatePeriod)
+	d.Enabled = helpers.MergeWithBool(d.Enabled, other.Enabled)
+	d.UpdatePeriod = helpers.MergeWithDurationPtr(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 = gosettings.OverrideWithPointer(d.Enabled, other.Enabled)
-	d.UpdatePeriod = gosettings.OverrideWithPointer(d.UpdatePeriod, other.UpdatePeriod)
+	d.Enabled = helpers.OverrideWithBool(d.Enabled, other.Enabled)
+	d.UpdatePeriod = helpers.OverrideWithDurationPtr(d.UpdatePeriod, other.UpdatePeriod)
 	d.Unbound.overrideWith(other.Unbound)
 	d.Blacklist.overrideWith(other.Blacklist)
 }

 func (d *DoT) setDefaults() {
-	d.Enabled = gosettings.DefaultPointer(d.Enabled, true)
+	d.Enabled = helpers.DefaultBool(d.Enabled, true)
 	const defaultUpdatePeriod = 24 * time.Hour
-	d.UpdatePeriod = gosettings.DefaultPointer(d.UpdatePeriod, defaultUpdatePeriod)
+	d.UpdatePeriod = helpers.DefaultDurationPtr(d.UpdatePeriod, defaultUpdatePeriod)
 	d.Unbound.setDefaults()
 	d.Blacklist.setDefaults()
 }
@@ -95,7 +95,7 @@ func (d DoT) String() string {
 func (d DoT) toLinesNode() (node *gotree.Node) {
 	node = gotree.New("DNS over TLS settings:")

-	node.Appendf("Enabled: %s", gosettings.BoolToYesNo(d.Enabled))
+	node.Appendf("Enabled: %s", helpers.BoolPtrToYesNo(d.Enabled))
 	if !*d.Enabled {
 		return node
 	}
--- a/internal/configuration/settings/errors.go
+++ b/internal/configuration/settings/errors.go
@@ -37,13 +37,10 @@ var (
 	ErrWireguardEndpointIPNotSet       = errors.New("endpoint IP is not set")
 	ErrWireguardEndpointPortNotAllowed = errors.New("endpoint port is not allowed")
 	ErrWireguardEndpointPortNotSet     = errors.New("endpoint port is not set")
-	ErrWireguardEndpointPortSet        = errors.New("endpoint port is set")
 	ErrWireguardInterfaceAddressNotSet = errors.New("interface address is not set")
-	ErrWireguardInterfaceAddressIPv6   = errors.New("interface address is IPv6 but IPv6 is not supported")
 	ErrWireguardInterfaceNotValid      = errors.New("interface name is not valid")
 	ErrWireguardPreSharedKeyNotSet     = errors.New("pre-shared key is not set")
 	ErrWireguardPrivateKeyNotSet       = errors.New("private key is not set")
 	ErrWireguardPublicKeyNotSet        = errors.New("public key is not set")
 	ErrWireguardPublicKeyNotValid      = errors.New("public key is not valid")
-	ErrWireguardImplementationNotValid = errors.New("implementation is not valid")
 )
--- a/internal/configuration/settings/firewall.go
+++ b/internal/configuration/settings/firewall.go
@@ -2,9 +2,9 @@ package settings

 import (
 	"fmt"
-	"net/netip"
+	"net"

-	"github.com/qdm12/gosettings"
+	"github.com/qdm12/gluetun/internal/configuration/settings/helpers"
 	"github.com/qdm12/gotree"
 )

@@ -12,7 +12,7 @@ import (
 type Firewall struct {
 	VPNInputPorts   []uint16
 	InputPorts      []uint16
-	OutboundSubnets []netip.Prefix
+	OutboundSubnets []net.IPNet
 	Enabled         *bool
 	Debug           *bool
 }
@@ -40,11 +40,11 @@ func hasZeroPort(ports []uint16) (has bool) {

 func (f *Firewall) copy() (copied Firewall) {
 	return Firewall{
-		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),
+		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),
 	}
 }

@@ -53,27 +53,27 @@ 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 = 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)
+	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)
 }

 // overrideWith overrides fields of the receiver
 // settings object with any field set in the other
 // settings.
 func (f *Firewall) overrideWith(other Firewall) {
-	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)
+	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)
 }

 func (f *Firewall) setDefaults() {
-	f.Enabled = gosettings.DefaultPointer(f.Enabled, true)
-	f.Debug = gosettings.DefaultPointer(f.Debug, false)
+	f.Enabled = helpers.DefaultBool(f.Enabled, true)
+	f.Debug = helpers.DefaultBool(f.Debug, false)
 }

 func (f Firewall) String() string {
@@ -83,7 +83,7 @@ func (f Firewall) String() string {
 func (f Firewall) toLinesNode() (node *gotree.Node) {
 	node = gotree.New("Firewall settings:")

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

--- a/internal/configuration/settings/health.go
+++ b/internal/configuration/settings/health.go
@@ -5,7 +5,7 @@ import (
 	"os"
 	"time"

-	"github.com/qdm12/gosettings"
+	"github.com/qdm12/gluetun/internal/configuration/settings/helpers"
 	"github.com/qdm12/gotree"
 	"github.com/qdm12/govalid/address"
 )
@@ -20,24 +20,18 @@ type Health struct {
 	// 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.
+	//  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
-	// 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
+	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)
@@ -57,7 +51,6 @@ func (h *Health) copy() (copied Health) {
 		ReadHeaderTimeout: h.ReadHeaderTimeout,
 		ReadTimeout:       h.ReadTimeout,
 		TargetAddress:     h.TargetAddress,
-		SuccessWait:       h.SuccessWait,
 		VPN:               h.VPN.copy(),
 	}
 }
@@ -65,11 +58,10 @@ func (h *Health) copy() (copied Health) {
 // MergeWith merges the other settings into any
 // unset field of the receiver settings object.
 func (h *Health) MergeWith(other Health) {
-	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.ServerAddress = helpers.MergeWithString(h.ServerAddress, other.ServerAddress)
+	h.ReadHeaderTimeout = helpers.MergeWithDuration(h.ReadHeaderTimeout, other.ReadHeaderTimeout)
+	h.ReadTimeout = helpers.MergeWithDuration(h.ReadTimeout, other.ReadTimeout)
+	h.TargetAddress = helpers.MergeWithString(h.TargetAddress, other.TargetAddress)
 	h.VPN.mergeWith(other.VPN)
 }

@@ -77,23 +69,20 @@ func (h *Health) MergeWith(other Health) {
 // settings object with any field set in the other
 // settings.
 func (h *Health) OverrideWith(other Health) {
-	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.ServerAddress = helpers.OverrideWithString(h.ServerAddress, other.ServerAddress)
+	h.ReadHeaderTimeout = helpers.OverrideWithDuration(h.ReadHeaderTimeout, other.ReadHeaderTimeout)
+	h.ReadTimeout = helpers.OverrideWithDuration(h.ReadTimeout, other.ReadTimeout)
+	h.TargetAddress = helpers.OverrideWithString(h.TargetAddress, other.TargetAddress)
 	h.VPN.overrideWith(other.VPN)
 }

 func (h *Health) SetDefaults() {
-	h.ServerAddress = gosettings.DefaultString(h.ServerAddress, "127.0.0.1:9999")
+	h.ServerAddress = helpers.DefaultString(h.ServerAddress, "127.0.0.1:9999")
 	const defaultReadHeaderTimeout = 100 * time.Millisecond
-	h.ReadHeaderTimeout = gosettings.DefaultNumber(h.ReadHeaderTimeout, defaultReadHeaderTimeout)
+	h.ReadHeaderTimeout = helpers.DefaultDuration(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.ReadTimeout = helpers.DefaultDuration(h.ReadTimeout, defaultReadTimeout)
+	h.TargetAddress = helpers.DefaultString(h.TargetAddress, "cloudflare.com:443")
 	h.VPN.setDefaults()
 }

@@ -105,7 +94,6 @@ 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"))
--- a/internal/configuration/settings/healthywait.go
+++ b/internal/configuration/settings/healthywait.go
@@ -3,7 +3,7 @@ package settings
 import (
 	"time"

-	"github.com/qdm12/gosettings"
+	"github.com/qdm12/gluetun/internal/configuration/settings/helpers"
 	"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:  gosettings.CopyPointer(h.Initial),
-		Addition: gosettings.CopyPointer(h.Addition),
+		Initial:  helpers.CopyDurationPtr(h.Initial),
+		Addition: helpers.CopyDurationPtr(h.Addition),
 	}
 }

 // mergeWith merges the other settings into any
 // unset field of the receiver settings object.
 func (h *HealthyWait) mergeWith(other HealthyWait) {
-	h.Initial = gosettings.MergeWithPointer(h.Initial, other.Initial)
-	h.Addition = gosettings.MergeWithPointer(h.Addition, other.Addition)
+	h.Initial = helpers.MergeWithDurationPtr(h.Initial, other.Initial)
+	h.Addition = helpers.MergeWithDurationPtr(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 = gosettings.OverrideWithPointer(h.Initial, other.Initial)
-	h.Addition = gosettings.OverrideWithPointer(h.Addition, other.Addition)
+	h.Initial = helpers.OverrideWithDurationPtr(h.Initial, other.Initial)
+	h.Addition = helpers.OverrideWithDurationPtr(h.Addition, other.Addition)
 }

 func (h *HealthyWait) setDefaults() {
 	const initialDurationDefault = 6 * time.Second
 	const additionDurationDefault = 5 * time.Second
-	h.Initial = gosettings.DefaultPointer(h.Initial, initialDurationDefault)
-	h.Addition = gosettings.DefaultPointer(h.Addition, additionDurationDefault)
+	h.Initial = helpers.DefaultDurationPtr(h.Initial, initialDurationDefault)
+	h.Addition = helpers.DefaultDurationPtr(h.Addition, additionDurationDefault)
 }

 func (h HealthyWait) String() string {
--- a/internal/configuration/settings/helpers/belong.go
+++ b/internal/configuration/settings/helpers/belong.go
@@ -1,6 +1,12 @@
 package helpers

-func IsOneOf[T comparable](value T, choices ...T) (ok bool) {
+import (
+	"errors"
+	"fmt"
+	"strings"
+)
+
+func IsOneOf(value string, choices ...string) (ok bool) {
 	for _, choice := range choices {
 		if value == choice {
 			return true
@@ -8,3 +14,39 @@ func IsOneOf[T comparable](value T, choices ...T) (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
+}
--- a/internal/configuration/settings/helpers/copy.go
+++ b/internal/configuration/settings/helpers/copy.go
@@ -0,0 +1,199 @@
+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
+}
--- a/internal/configuration/settings/helpers/default.go
+++ b/internal/configuration/settings/helpers/default.go
@@ -0,0 +1,110 @@
+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 != 0 {
+		return existing
+	}
+	return defaultValue
+}
+
+func DefaultDurationPtr(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
+}
--- a/internal/configuration/settings/helpers/files.go
+++ b/internal/configuration/settings/helpers/files.go
@@ -0,0 +1,31 @@
+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
+}
--- a/internal/configuration/settings/helpers/merge.go
+++ b/internal/configuration/settings/helpers/merge.go
@@ -0,0 +1,266 @@
+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 != 0 {
+		return existing
+	}
+	return other
+}
+
+func MergeWithDurationPtr(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
+}
--- a/internal/configuration/settings/helpers/messages.go
+++ b/internal/configuration/settings/helpers/messages.go
@@ -0,0 +1,29 @@
+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
+}
--- a/internal/configuration/settings/helpers/obfuscate.go
+++ b/internal/configuration/settings/helpers/obfuscate.go
@@ -0,0 +1,25 @@
+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]"
+}
--- a/internal/configuration/settings/helpers/override.go
+++ b/internal/configuration/settings/helpers/override.go
@@ -0,0 +1,173 @@
+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 == 0 {
+		return existing
+	}
+	return other
+}
+
+func OverrideWithDurationPtr(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
+}
--- a/internal/configuration/settings/helpers/pointers.go
+++ b/internal/configuration/settings/helpers/pointers.go
@@ -0,0 +1,11 @@
+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 }
--- a/internal/configuration/settings/helpers/string.go
+++ b/internal/configuration/settings/helpers/string.go
@@ -1,5 +1,12 @@
 package helpers

+func BoolPtrToYesNo(b *bool) string {
+	if *b {
+		return "yes"
+	}
+	return "no"
+}
+
 func TCPPtrToString(tcp *bool) string {
 	if *tcp {
 		return "TCP"
--- a/internal/configuration/settings/httpproxy.go
+++ b/internal/configuration/settings/httpproxy.go
@@ -5,7 +5,7 @@ import (
 	"os"
 	"time"

-	"github.com/qdm12/gosettings"
+	"github.com/qdm12/gluetun/internal/configuration/settings/helpers"
 	"github.com/qdm12/gotree"
 	"github.com/qdm12/govalid/address"
 )
@@ -46,7 +46,7 @@ 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)
 	}
@@ -56,12 +56,12 @@ func (h HTTPProxy) validate() (err error) {

 func (h *HTTPProxy) copy() (copied HTTPProxy) {
 	return HTTPProxy{
-		User:              gosettings.CopyPointer(h.User),
-		Password:          gosettings.CopyPointer(h.Password),
+		User:              helpers.CopyStringPtr(h.User),
+		Password:          helpers.CopyStringPtr(h.Password),
 		ListeningAddress:  h.ListeningAddress,
-		Enabled:           gosettings.CopyPointer(h.Enabled),
-		Stealth:           gosettings.CopyPointer(h.Stealth),
-		Log:               gosettings.CopyPointer(h.Log),
+		Enabled:           helpers.CopyBoolPtr(h.Enabled),
+		Stealth:           helpers.CopyBoolPtr(h.Stealth),
+		Log:               helpers.CopyBoolPtr(h.Log),
 		ReadHeaderTimeout: h.ReadHeaderTimeout,
 		ReadTimeout:       h.ReadTimeout,
 	}
@@ -70,41 +70,41 @@ func (h *HTTPProxy) copy() (copied HTTPProxy) {
 // mergeWith merges the other settings into any
 // unset field of the receiver settings object.
 func (h *HTTPProxy) mergeWith(other HTTPProxy) {
-	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)
+	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.ReadHeaderTimeout = helpers.MergeWithDuration(h.ReadHeaderTimeout, other.ReadHeaderTimeout)
+	h.ReadTimeout = helpers.MergeWithDuration(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 = 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)
+	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.ReadHeaderTimeout = helpers.OverrideWithDuration(h.ReadHeaderTimeout, other.ReadHeaderTimeout)
+	h.ReadTimeout = helpers.OverrideWithDuration(h.ReadTimeout, other.ReadTimeout)
 }

 func (h *HTTPProxy) setDefaults() {
-	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)
+	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)
 	const defaultReadHeaderTimeout = time.Second
-	h.ReadHeaderTimeout = gosettings.DefaultNumber(h.ReadHeaderTimeout, defaultReadHeaderTimeout)
+	h.ReadHeaderTimeout = helpers.DefaultDuration(h.ReadHeaderTimeout, defaultReadHeaderTimeout)
 	const defaultReadTimeout = 3 * time.Second
-	h.ReadTimeout = gosettings.DefaultNumber(h.ReadTimeout, defaultReadTimeout)
+	h.ReadTimeout = helpers.DefaultDuration(h.ReadTimeout, defaultReadTimeout)
 }

 func (h HTTPProxy) String() string {
@@ -113,16 +113,16 @@ func (h HTTPProxy) String() string {

 func (h HTTPProxy) toLinesNode() (node *gotree.Node) {
 	node = gotree.New("HTTP proxy settings:")
-	node.Appendf("Enabled: %s", gosettings.BoolToYesNo(h.Enabled))
+	node.Appendf("Enabled: %s", helpers.BoolPtrToYesNo(h.Enabled))
 	if !*h.Enabled {
 		return node
 	}

 	node.Appendf("Listening address: %s", h.ListeningAddress)
 	node.Appendf("User: %s", *h.User)
-	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("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("Read header timeout: %s", h.ReadHeaderTimeout)
 	node.Appendf("Read timeout: %s", h.ReadTimeout)

--- a/internal/configuration/settings/log.go
+++ b/internal/configuration/settings/log.go
@@ -1,7 +1,7 @@
 package settings

 import (
-	"github.com/qdm12/gosettings"
+	"github.com/qdm12/gluetun/internal/configuration/settings/helpers"
 	"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: gosettings.CopyPointer(l.Level),
+		Level: helpers.CopyLogLevelPtr(l.Level),
 	}
 }

 // mergeWith merges the other settings into any
 // unset field of the receiver settings object.
 func (l *Log) mergeWith(other Log) {
-	l.Level = gosettings.MergeWithPointer(l.Level, other.Level)
+	l.Level = helpers.MergeWithLogLevel(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 = gosettings.OverrideWithPointer(l.Level, other.Level)
+	l.Level = helpers.OverrideWithLogLevel(l.Level, other.Level)
 }

 func (l *Log) setDefaults() {
-	l.Level = gosettings.DefaultPointer(l.Level, log.LevelInfo)
+	l.Level = helpers.DefaultLogLevel(l.Level, log.LevelInfo)
 }

 func (l Log) String() string {
--- a/internal/configuration/settings/netaddr.go
+++ b/internal/configuration/settings/netaddr.go
@@ -1,36 +0,0 @@
-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
-}
--- a/internal/configuration/settings/nordvpn_retro.go
+++ b/internal/configuration/settings/nordvpn_retro.go
@@ -1,42 +0,0 @@
-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
-}
--- a/internal/configuration/settings/openvpn.go
+++ b/internal/configuration/settings/openvpn.go
@@ -4,109 +4,112 @@ 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 "2.5" or "2.6".
-	Version string `json:"version"`
+	// It can only be "2.4" or "2.5".
+	Version string
 	// User is the OpenVPN authentication username.
 	// 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"`
+	User *string
 	// Password is the OpenVPN authentication password.
 	// 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"`
+	Password *string
 	// 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 `json:"config_file_path"`
+	ConfFile *string
 	// Ciphers is a list of ciphers to use for OpenVPN,
 	// different from the ones specified by the VPN
 	// service provider configuration files.
-	Ciphers []string `json:"ciphers"`
+	Ciphers []string
 	// 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 `json:"auth"`
-	// Cert is the base64 encoded DER of an OpenVPN certificate for the <cert> block.
+	Auth *string
+	// Cert is the OpenVPN certificate for the <cert> block.
 	// This is notably used by Cyberghost and VPN secure.
 	// It can be set to the empty string to be ignored.
 	// It cannot be nil in the internal state.
-	Cert *string `json:"cert"`
-	// Key is the base64 encoded DER of an OpenVPN key.
+	Cert *string
+	// Key is the OpenVPN key.
 	// This is used by Cyberghost and VPN Unlimited.
 	// It can be set to the empty string to be ignored.
 	// It cannot be nil in the internal state.
-	Key *string `json:"key"`
-	// EncryptedKey is the base64 encoded DER of an encrypted key for OpenVPN.
-	// It is used by VPN secure.
+	Key *string
+	// EncryptedKey is the content 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"`
+	EncryptedKey *string
 	// 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"`
+	KeyPassphrase *string
 	// PIAEncPreset is the encryption preset for
 	// Private Internet Access. It can be set to an
 	// empty string for other providers.
-	PIAEncPreset *string `json:"pia_encryption_preset"`
+	PIAEncPreset *string
+	// IPv6 is set to true if IPv6 routing should be
+	// set to be tunnel in OpenVPN, and false otherwise.
+	// It cannot be nil in the internal state.
+	IPv6 *bool // TODO automate like with Wireguard
 	// MSSFix is the value (1 to 10000) to set for the
 	// mssfix option for OpenVPN. It is ignored if set to 0.
 	// It cannot be nil in the internal state.
-	MSSFix *uint16 `json:"mssfix"`
+	MSSFix *uint16
 	// Interface is the OpenVPN device interface name.
 	// It cannot be an empty string in the internal state.
-	Interface string `json:"interface"`
+	Interface string
 	// ProcessUser is the OpenVPN process OS username
 	// to use. It cannot be empty in the internal state.
 	// It defaults to 'root'.
-	ProcessUser string `json:"process_user"`
+	ProcessUser string
 	// Verbosity is the OpenVPN verbosity level from 0 to 6.
 	// It cannot be nil in the internal state.
-	Verbosity *int `json:"verbosity"`
+	Verbosity *int
 	// Flags is a slice of additional flags to be passed
 	// to the OpenVPN program.
-	Flags []string `json:"flags"`
+	Flags []string
 }

 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.Openvpn25, openvpn.Openvpn26}
-	if err = validate.IsOneOf(o.Version, validVersions...); err != nil {
-		return fmt.Errorf("%w: %w", ErrOpenVPNVersionIsNotValid, err)
+	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, ", "))
 	}

 	isCustom := vpnProvider == providers.Custom
-	isUserRequired := !isCustom &&
-		vpnProvider != providers.Airvpn &&
-		vpnProvider != providers.VPNSecure
+	isUserRequired := !isCustom && vpnProvider != providers.VPNSecure

 	if isUserRequired && *o.User == "" {
-		return fmt.Errorf("%w", ErrOpenVPNUserIsEmpty)
+		return ErrOpenVPNUserIsEmpty
 	}

 	passwordRequired := isUserRequired &&
 		(vpnProvider != providers.Ivpn || !ivpnAccountID.MatchString(*o.User))

 	if passwordRequired && *o.Password == "" {
-		return fmt.Errorf("%w", ErrOpenVPNPasswordIsEmpty)
+		return ErrOpenVPNPasswordIsEmpty
 	}

 	err = validateOpenVPNConfigFilepath(isCustom, *o.ConfFile)
@@ -159,10 +162,10 @@ func validateOpenVPNConfigFilepath(isCustom bool,
 	}

 	if confFile == "" {
-		return fmt.Errorf("%w", ErrFilepathMissing)
+		return ErrFilepathMissing
 	}

-	err = validate.FileExists(confFile)
+	err = helpers.FileExists(confFile)
 	if err != nil {
 		return err
 	}
@@ -170,7 +173,7 @@ func validateOpenVPNConfigFilepath(isCustom bool,
 	extractor := extract.New()
 	_, _, err = extractor.Data(confFile)
 	if err != nil {
-		return fmt.Errorf("extracting information from custom configuration file: %w", err)
+		return fmt.Errorf("failed extracting information from custom configuration file: %w", err)
 	}

 	return nil
@@ -180,12 +183,11 @@ func validateOpenVPNClientCertificate(vpnProvider,
 	clientCert string) (err error) {
 	switch vpnProvider {
 	case
-		providers.Airvpn,
 		providers.Cyberghost,
 		providers.VPNSecure,
 		providers.VPNUnlimited:
 		if clientCert == "" {
-			return fmt.Errorf("%w", ErrMissingValue)
+			return ErrMissingValue
 		}
 	}

@@ -203,12 +205,11 @@ func validateOpenVPNClientCertificate(vpnProvider,
 func validateOpenVPNClientKey(vpnProvider, clientKey string) (err error) {
 	switch vpnProvider {
 	case
-		providers.Airvpn,
 		providers.Cyberghost,
 		providers.VPNUnlimited,
 		providers.Wevpn:
 		if clientKey == "" {
-			return fmt.Errorf("%w", ErrMissingValue)
+			return ErrMissingValue
 		}
 	}

@@ -226,7 +227,7 @@ func validateOpenVPNClientKey(vpnProvider, clientKey string) (err error) {
 func validateOpenVPNEncryptedKey(vpnProvider,
 	encryptedPrivateKey string) (err error) {
 	if vpnProvider == providers.VPNSecure && encryptedPrivateKey == "" {
-		return fmt.Errorf("%w", ErrMissingValue)
+		return ErrMissingValue
 	}

 	if encryptedPrivateKey == "" {
@@ -243,92 +244,97 @@ func validateOpenVPNEncryptedKey(vpnProvider,
 func (o *OpenVPN) copy() (copied OpenVPN) {
 	return OpenVPN{
 		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),
+		User:          helpers.CopyStringPtr(o.User),
+		Password:      helpers.CopyStringPtr(o.Password),
+		ConfFile:      helpers.CopyStringPtr(o.ConfFile),
+		Ciphers:       helpers.CopyStringSlice(o.Ciphers),
+		Auth:          helpers.CopyStringPtr(o.Auth),
+		Cert:          helpers.CopyStringPtr(o.Cert),
+		Key:           helpers.CopyStringPtr(o.Key),
+		EncryptedKey:  helpers.CopyStringPtr(o.EncryptedKey),
+		KeyPassphrase: helpers.CopyStringPtr(o.KeyPassphrase),
+		PIAEncPreset:  helpers.CopyStringPtr(o.PIAEncPreset),
+		IPv6:          helpers.CopyBoolPtr(o.IPv6),
+		MSSFix:        helpers.CopyUint16Ptr(o.MSSFix),
 		Interface:     o.Interface,
 		ProcessUser:   o.ProcessUser,
-		Verbosity:     gosettings.CopyPointer(o.Verbosity),
-		Flags:         gosettings.CopySlice(o.Flags),
+		Verbosity:     helpers.CopyIntPtr(o.Verbosity),
+		Flags:         helpers.CopyStringSlice(o.Flags),
 	}
 }

 // mergeWith merges the other settings into any
 // unset field of the receiver settings object.
 func (o *OpenVPN) mergeWith(other OpenVPN) {
-	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)
+	o.Version = helpers.MergeWithString(o.Version, other.Version)
+	o.User = helpers.MergeWithStringPtr(o.User, other.User)
+	o.Password = helpers.MergeWithStringPtr(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.Cert = helpers.MergeWithStringPtr(o.Cert, other.Cert)
+	o.Key = helpers.MergeWithStringPtr(o.Key, other.Key)
+	o.EncryptedKey = helpers.MergeWithStringPtr(o.EncryptedKey, other.EncryptedKey)
+	o.KeyPassphrase = helpers.MergeWithStringPtr(o.KeyPassphrase, other.KeyPassphrase)
+	o.PIAEncPreset = helpers.MergeWithStringPtr(o.PIAEncPreset, other.PIAEncPreset)
+	o.IPv6 = helpers.MergeWithBool(o.IPv6, other.IPv6)
+	o.MSSFix = helpers.MergeWithUint16(o.MSSFix, other.MSSFix)
+	o.Interface = helpers.MergeWithString(o.Interface, other.Interface)
+	o.ProcessUser = helpers.MergeWithString(o.ProcessUser, other.ProcessUser)
+	o.Verbosity = helpers.MergeWithIntPtr(o.Verbosity, other.Verbosity)
+	o.Flags = helpers.MergeStringSlices(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 = 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)
+	o.Version = helpers.OverrideWithString(o.Version, other.Version)
+	o.User = helpers.OverrideWithStringPtr(o.User, other.User)
+	o.Password = helpers.OverrideWithStringPtr(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.Cert = helpers.OverrideWithStringPtr(o.Cert, other.Cert)
+	o.Key = helpers.OverrideWithStringPtr(o.Key, other.Key)
+	o.EncryptedKey = helpers.OverrideWithStringPtr(o.EncryptedKey, other.EncryptedKey)
+	o.KeyPassphrase = helpers.OverrideWithStringPtr(o.KeyPassphrase, other.KeyPassphrase)
+	o.PIAEncPreset = helpers.OverrideWithStringPtr(o.PIAEncPreset, other.PIAEncPreset)
+	o.IPv6 = helpers.OverrideWithBool(o.IPv6, other.IPv6)
+	o.MSSFix = helpers.OverrideWithUint16(o.MSSFix, other.MSSFix)
+	o.Interface = helpers.OverrideWithString(o.Interface, other.Interface)
+	o.ProcessUser = helpers.OverrideWithString(o.ProcessUser, other.ProcessUser)
+	o.Verbosity = helpers.OverrideWithIntPtr(o.Verbosity, other.Verbosity)
+	o.Flags = helpers.OverrideWithStringSlice(o.Flags, other.Flags)
 }

 func (o *OpenVPN) setDefaults(vpnProvider string) {
-	o.Version = gosettings.DefaultString(o.Version, openvpn.Openvpn25)
-	o.User = gosettings.DefaultPointer(o.User, "")
+	o.Version = helpers.DefaultString(o.Version, openvpn.Openvpn25)
+	o.User = helpers.DefaultStringPtr(o.User, "")
 	if vpnProvider == providers.Mullvad {
-		o.Password = gosettings.DefaultPointer(o.Password, "m")
+		o.Password = helpers.DefaultStringPtr(o.Password, "m")
 	} else {
-		o.Password = gosettings.DefaultPointer(o.Password, "")
+		o.Password = helpers.DefaultStringPtr(o.Password, "")
 	}

-	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, "")
+	o.ConfFile = helpers.DefaultStringPtr(o.ConfFile, "")
+	o.Auth = helpers.DefaultStringPtr(o.Auth, "")
+	o.Cert = helpers.DefaultStringPtr(o.Cert, "")
+	o.Key = helpers.DefaultStringPtr(o.Key, "")
+	o.EncryptedKey = helpers.DefaultStringPtr(o.EncryptedKey, "")
+	o.KeyPassphrase = helpers.DefaultStringPtr(o.KeyPassphrase, "")

 	var defaultEncPreset string
 	if vpnProvider == providers.PrivateInternetAccess {
 		defaultEncPreset = presets.Strong
 	}
-	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)
+	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)
 }

 func (o OpenVPN) String() string {
@@ -338,8 +344,8 @@ 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", gosettings.ObfuscateKey(*o.User))
-	node.Appendf("Password: %s", gosettings.ObfuscateKey(*o.Password))
+	node.Appendf("User: %s", helpers.ObfuscatePassword(*o.User))
+	node.Appendf("Password: %s", helpers.ObfuscatePassword(*o.Password))

 	if *o.ConfFile != "" {
 		node.Appendf("Custom configuration file: %s", *o.ConfFile)
@@ -354,22 +360,24 @@ func (o OpenVPN) toLinesNode() (node *gotree.Node) {
 	}

 	if *o.Cert != "" {
-		node.Appendf("Client crt: %s", gosettings.ObfuscateKey(*o.Cert))
+		node.Appendf("Client crt: %s", helpers.ObfuscateData(*o.Cert))
 	}

 	if *o.Key != "" {
-		node.Appendf("Client key: %s", gosettings.ObfuscateKey(*o.Key))
+		node.Appendf("Client key: %s", helpers.ObfuscateData(*o.Key))
 	}

 	if *o.EncryptedKey != "" {
 		node.Appendf("Encrypted key: %s (key passhrapse %s)",
-			gosettings.ObfuscateKey(*o.EncryptedKey), gosettings.ObfuscateKey(*o.KeyPassphrase))
+			helpers.ObfuscateData(*o.EncryptedKey), helpers.ObfuscatePassword(*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)
 	}
--- a/internal/configuration/settings/openvpnselection.go
+++ b/internal/configuration/settings/openvpnselection.go
@@ -6,8 +6,6 @@ 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"
 )

@@ -16,25 +14,25 @@ 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 `json:"config_file_path"`
+	ConfFile *string
 	// TCP is true if the OpenVPN protocol is TCP,
 	// and false for UDP.
 	// It cannot be nil in the internal state.
-	TCP *bool `json:"tcp"`
+	TCP *bool
 	// 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 `json:"custom_port"`
+	CustomPort *uint16 // HideMyAss, Mullvad, PIA, ProtonVPN, WeVPN, Windscribe
 	// PIAEncPreset is the encryption preset for
 	// Private Internet Access. It can be set to an
 	// empty string for other providers.
-	PIAEncPreset *string `json:"pia_encryption_preset"`
+	PIAEncPreset *string
 }

 func (o OpenVPNSelection) validate(vpnProvider string) (err error) {
 	// Validate ConfFile
 	if confFile := *o.ConfFile; confFile != "" {
-		err := validate.FileExists(confFile)
+		err := helpers.FileExists(confFile)
 		if err != nil {
 			return fmt.Errorf("configuration file: %w", err)
 		}
@@ -69,12 +67,6 @@ func (o OpenVPNSelection) validate(vpnProvider string) (err error) {
 		default:
 			var allowedTCP, allowedUDP []uint16
 			switch vpnProvider {
-			case providers.Airvpn:
-				allowedTCP = []uint16{
-					53, 80, 443, // IP in 1, 3
-					1194, 2018, 41185, // IP in 1, 2, 3, 4
-				}
-				allowedUDP = []uint16{53, 80, 443, 1194, 2018, 41185}
 			case providers.Ivpn:
 				allowedTCP = []uint16{80, 443, 1143}
 				allowedUDP = []uint16{53, 1194, 2049, 2050}
@@ -101,14 +93,14 @@ func (o OpenVPNSelection) validate(vpnProvider string) (err error) {
 				allowedUDP = []uint16{53, 80, 123, 443, 1194, 54783}
 			}

-			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)
+			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))
 			}
 		}
 	}
@@ -120,8 +112,10 @@ func (o OpenVPNSelection) validate(vpnProvider string) (err error) {
 			presets.Normal,
 			presets.Strong,
 		}
-		if err = validate.IsOneOf(*o.PIAEncPreset, validEncryptionPresets...); err != nil {
-			return fmt.Errorf("%w: %w", ErrOpenVPNEncryptionPresetNotValid, err)
+		if !helpers.IsOneOf(*o.PIAEncPreset, validEncryptionPresets...) {
+			return fmt.Errorf("%w: %s; valid presets are %s",
+				ErrOpenVPNEncryptionPresetNotValid, *o.PIAEncPreset,
+				helpers.ChoicesOrString(validEncryptionPresets))
 		}
 	}

@@ -130,37 +124,37 @@ func (o OpenVPNSelection) validate(vpnProvider string) (err error) {

 func (o *OpenVPNSelection) copy() (copied OpenVPNSelection) {
 	return OpenVPNSelection{
-		ConfFile:     gosettings.CopyPointer(o.ConfFile),
-		TCP:          gosettings.CopyPointer(o.TCP),
-		CustomPort:   gosettings.CopyPointer(o.CustomPort),
-		PIAEncPreset: gosettings.CopyPointer(o.PIAEncPreset),
+		ConfFile:     helpers.CopyStringPtr(o.ConfFile),
+		TCP:          helpers.CopyBoolPtr(o.TCP),
+		CustomPort:   helpers.CopyUint16Ptr(o.CustomPort),
+		PIAEncPreset: helpers.CopyStringPtr(o.PIAEncPreset),
 	}
 }

 func (o *OpenVPNSelection) mergeWith(other OpenVPNSelection) {
-	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)
+	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)
 }

 func (o *OpenVPNSelection) overrideWith(other OpenVPNSelection) {
-	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)
+	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)
 }

 func (o *OpenVPNSelection) setDefaults(vpnProvider string) {
-	o.ConfFile = gosettings.DefaultPointer(o.ConfFile, "")
-	o.TCP = gosettings.DefaultPointer(o.TCP, false)
-	o.CustomPort = gosettings.DefaultPointer(o.CustomPort, 0)
+	o.ConfFile = helpers.DefaultStringPtr(o.ConfFile, "")
+	o.TCP = helpers.DefaultBool(o.TCP, false)
+	o.CustomPort = helpers.DefaultUint16(o.CustomPort, 0)

 	var defaultEncPreset string
 	if vpnProvider == providers.PrivateInternetAccess {
 		defaultEncPreset = presets.Strong
 	}
-	o.PIAEncPreset = gosettings.DefaultPointer(o.PIAEncPreset, defaultEncPreset)
+	o.PIAEncPreset = helpers.DefaultStringPtr(o.PIAEncPreset, defaultEncPreset)
 }

 func (o OpenVPNSelection) String() string {
--- a/internal/configuration/settings/portforward.go
+++ b/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"
 )

@@ -14,12 +14,12 @@ import (
 type PortForwarding struct {
 	// Enabled is true if port forwarding should be activated.
 	// It cannot be nil for the internal state.
-	Enabled *bool `json:"enabled"`
+	Enabled *bool
 	// 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 `json:"status_file_path"`
+	Filepath *string
 }

 func (p PortForwarding) validate(vpnProvider string) (err error) {
@@ -29,8 +29,9 @@ func (p PortForwarding) validate(vpnProvider string) (err error) {

 	// Validate Enabled
 	validProviders := []string{providers.PrivateInternetAccess}
-	if err = validate.IsOneOf(vpnProvider, validProviders...); err != nil {
-		return fmt.Errorf("%w: %w", ErrPortForwardingEnabled, err)
+	if !helpers.IsOneOf(vpnProvider, validProviders...) {
+		return fmt.Errorf("%w: for provider %s, it is only available for %s",
+			ErrPortForwardingEnabled, vpnProvider, strings.Join(validProviders, ", "))
 	}

 	// Validate Filepath
@@ -46,24 +47,24 @@ func (p PortForwarding) validate(vpnProvider string) (err error) {

 func (p *PortForwarding) copy() (copied PortForwarding) {
 	return PortForwarding{
-		Enabled:  gosettings.CopyPointer(p.Enabled),
-		Filepath: gosettings.CopyPointer(p.Filepath),
+		Enabled:  helpers.CopyBoolPtr(p.Enabled),
+		Filepath: helpers.CopyStringPtr(p.Filepath),
 	}
 }

 func (p *PortForwarding) mergeWith(other PortForwarding) {
-	p.Enabled = gosettings.MergeWithPointer(p.Enabled, other.Enabled)
-	p.Filepath = gosettings.MergeWithPointer(p.Filepath, other.Filepath)
+	p.Enabled = helpers.MergeWithBool(p.Enabled, other.Enabled)
+	p.Filepath = helpers.MergeWithStringPtr(p.Filepath, other.Filepath)
 }

 func (p *PortForwarding) overrideWith(other PortForwarding) {
-	p.Enabled = gosettings.OverrideWithPointer(p.Enabled, other.Enabled)
-	p.Filepath = gosettings.OverrideWithPointer(p.Filepath, other.Filepath)
+	p.Enabled = helpers.OverrideWithBool(p.Enabled, other.Enabled)
+	p.Filepath = helpers.OverrideWithStringPtr(p.Filepath, other.Filepath)
 }

 func (p *PortForwarding) setDefaults() {
-	p.Enabled = gosettings.DefaultPointer(p.Enabled, false)
-	p.Filepath = gosettings.DefaultPointer(p.Filepath, "/tmp/gluetun/forwarded_port")
+	p.Enabled = helpers.DefaultBool(p.Enabled, false)
+	p.Filepath = helpers.DefaultStringPtr(p.Filepath, "/tmp/gluetun/forwarded_port")
 }

 func (p PortForwarding) String() string {
--- a/internal/configuration/settings/provider.go
+++ b/internal/configuration/settings/provider.go
@@ -3,10 +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/gosettings"
-	"github.com/qdm12/gosettings/validate"
 	"github.com/qdm12/gotree"
 )

@@ -14,12 +13,12 @@ import (
 type Provider struct {
 	// Name is the VPN service provider name.
 	// It cannot be nil in the internal state.
-	Name *string `json:"name"`
+	Name *string
 	// ServerSelection is the settings to
 	// select the VPN server.
-	ServerSelection ServerSelection `json:"server_selection"`
+	ServerSelection ServerSelection
 	// PortForwarding is the settings about port forwarding.
-	PortForwarding PortForwarding `json:"port_forwarding"`
+	PortForwarding PortForwarding
 }

 // TODO v4 remove pointer for receiver (because of Surfshark).
@@ -31,17 +30,15 @@ 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 err = validate.IsOneOf(*p.Name, validNames...); err != nil {
-		return fmt.Errorf("%w for Wireguard: %w", ErrVPNProviderNameNotValid, err)
+	if !helpers.IsOneOf(*p.Name, validNames...) {
+		return fmt.Errorf("%w: %q can only be one of %s",
+			ErrVPNProviderNameNotValid, *p.Name, helpers.ChoicesOrString(validNames))
 	}

 	err = p.ServerSelection.validate(*p.Name, storage)
@@ -59,26 +56,26 @@ func (p *Provider) validate(vpnType string, storage Storage) (err error) {

 func (p *Provider) copy() (copied Provider) {
 	return Provider{
-		Name:            gosettings.CopyPointer(p.Name),
+		Name:            helpers.CopyStringPtr(p.Name),
 		ServerSelection: p.ServerSelection.copy(),
 		PortForwarding:  p.PortForwarding.copy(),
 	}
 }

 func (p *Provider) mergeWith(other Provider) {
-	p.Name = gosettings.MergeWithPointer(p.Name, other.Name)
+	p.Name = helpers.MergeWithStringPtr(p.Name, other.Name)
 	p.ServerSelection.mergeWith(other.ServerSelection)
 	p.PortForwarding.mergeWith(other.PortForwarding)
 }

 func (p *Provider) overrideWith(other Provider) {
-	p.Name = gosettings.OverrideWithPointer(p.Name, other.Name)
+	p.Name = helpers.OverrideWithStringPtr(p.Name, other.Name)
 	p.ServerSelection.overrideWith(other.ServerSelection)
 	p.PortForwarding.overrideWith(other.PortForwarding)
 }

 func (p *Provider) setDefaults() {
-	p.Name = gosettings.DefaultPointer(p.Name, providers.PrivateInternetAccess)
+	p.Name = helpers.DefaultStringPtr(p.Name, providers.PrivateInternetAccess)
 	p.ServerSelection.setDefaults(*p.Name)
 	p.PortForwarding.setDefaults()
 }
--- a/internal/configuration/settings/publicip.go
+++ b/internal/configuration/settings/publicip.go
@@ -5,7 +5,7 @@ import (
 	"path/filepath"
 	"time"

-	"github.com/qdm12/gosettings"
+	"github.com/qdm12/gluetun/internal/configuration/settings/helpers"
 	"github.com/qdm12/gotree"
 )

@@ -42,25 +42,25 @@ func (p PublicIP) validate() (err error) {

 func (p *PublicIP) copy() (copied PublicIP) {
 	return PublicIP{
-		Period:     gosettings.CopyPointer(p.Period),
-		IPFilepath: gosettings.CopyPointer(p.IPFilepath),
+		Period:     helpers.CopyDurationPtr(p.Period),
+		IPFilepath: helpers.CopyStringPtr(p.IPFilepath),
 	}
 }

 func (p *PublicIP) mergeWith(other PublicIP) {
-	p.Period = gosettings.MergeWithPointer(p.Period, other.Period)
-	p.IPFilepath = gosettings.MergeWithPointer(p.IPFilepath, other.IPFilepath)
+	p.Period = helpers.MergeWithDurationPtr(p.Period, other.Period)
+	p.IPFilepath = helpers.MergeWithStringPtr(p.IPFilepath, other.IPFilepath)
 }

 func (p *PublicIP) overrideWith(other PublicIP) {
-	p.Period = gosettings.OverrideWithPointer(p.Period, other.Period)
-	p.IPFilepath = gosettings.OverrideWithPointer(p.IPFilepath, other.IPFilepath)
+	p.Period = helpers.OverrideWithDurationPtr(p.Period, other.Period)
+	p.IPFilepath = helpers.OverrideWithStringPtr(p.IPFilepath, other.IPFilepath)
 }

 func (p *PublicIP) setDefaults() {
 	const defaultPeriod = 12 * time.Hour
-	p.Period = gosettings.DefaultPointer(p.Period, defaultPeriod)
-	p.IPFilepath = gosettings.DefaultPointer(p.IPFilepath, "/tmp/gluetun/ip")
+	p.Period = helpers.DefaultDurationPtr(p.Period, defaultPeriod)
+	p.IPFilepath = helpers.DefaultStringPtr(p.IPFilepath, "/tmp/gluetun/ip")
 }

 func (p PublicIP) String() string {
--- a/internal/configuration/settings/server.go
+++ b/internal/configuration/settings/server.go
@@ -6,7 +6,7 @@ import (
 	"os"
 	"strconv"

-	"github.com/qdm12/gosettings"
+	"github.com/qdm12/gluetun/internal/configuration/settings/helpers"
 	"github.com/qdm12/gotree"
 )

@@ -43,29 +43,29 @@ func (c ControlServer) validate() (err error) {

 func (c *ControlServer) copy() (copied ControlServer) {
 	return ControlServer{
-		Address: gosettings.CopyPointer(c.Address),
-		Log:     gosettings.CopyPointer(c.Log),
+		Address: helpers.CopyStringPtr(c.Address),
+		Log:     helpers.CopyBoolPtr(c.Log),
 	}
 }

 // mergeWith merges the other settings into any
 // unset field of the receiver settings object.
 func (c *ControlServer) mergeWith(other ControlServer) {
-	c.Address = gosettings.MergeWithPointer(c.Address, other.Address)
-	c.Log = gosettings.MergeWithPointer(c.Log, other.Log)
+	c.Address = helpers.MergeWithStringPtr(c.Address, other.Address)
+	c.Log = helpers.MergeWithBool(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 = gosettings.OverrideWithPointer(c.Address, other.Address)
-	c.Log = gosettings.OverrideWithPointer(c.Log, other.Log)
+	c.Address = helpers.OverrideWithStringPtr(c.Address, other.Address)
+	c.Log = helpers.OverrideWithBool(c.Log, other.Log)
 }

 func (c *ControlServer) setDefaults() {
-	c.Address = gosettings.DefaultPointer(c.Address, ":8000")
-	c.Log = gosettings.DefaultPointer(c.Log, true)
+	c.Address = helpers.DefaultStringPtr(c.Address, ":8000")
+	c.Log = helpers.DefaultBool(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", gosettings.BoolToYesNo(c.Log))
+	node.Appendf("Logging: %s", helpers.BoolPtrToYesNo(c.Log))
 	return node
 }
--- a/internal/configuration/settings/serverselection.go
+++ b/internal/configuration/settings/serverselection.go
@@ -3,7 +3,7 @@ package settings
 import (
 	"errors"
 	"fmt"
-	"net/netip"
+	"net"
 	"strings"

 	"github.com/qdm12/gluetun/internal/configuration/settings/helpers"
@@ -11,8 +11,6 @@ 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"
 )

@@ -20,50 +18,50 @@ 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 `json:"vpn"`
+	VPN string
 	// TargetIP is the server endpoint IP address to use.
 	// It will override any IP address from the picked
-	// built-in server. It cannot be the empty value in the internal
-	// state, and can be set to the unspecified address to indicate
+	// built-in server. It cannot be nil in the internal
+	// state, and can be set to an empty net.IP{} to indicate
 	// there is not target IP address to use.
-	TargetIP netip.Addr `json:"target_ip"`
+	TargetIP net.IP
 	// Counties is the list of countries to filter VPN servers with.
-	Countries []string `json:"countries"`
+	Countries []string
 	// Regions is the list of regions to filter VPN servers with.
-	Regions []string `json:"regions"`
+	Regions []string
 	// Cities is the list of cities to filter VPN servers with.
-	Cities []string `json:"cities"`
+	Cities []string
 	// ISPs is the list of ISP names to filter VPN servers with.
-	ISPs []string `json:"isps"`
+	ISPs []string
 	// Names is the list of server names to filter VPN servers with.
-	Names []string `json:"names"`
+	Names []string
 	// Numbers is the list of server numbers to filter VPN servers with.
-	Numbers []uint16 `json:"numbers"`
+	Numbers []uint16
 	// Hostnames is the list of hostnames to filter VPN servers with.
-	Hostnames []string `json:"hostnames"`
+	Hostnames []string
 	// OwnedOnly is true if VPN provider servers that are not owned
 	// should be filtered. This is used with Mullvad.
-	OwnedOnly *bool `json:"owned_only"`
+	OwnedOnly *bool
 	// FreeOnly is true if VPN servers that are not free should
 	// be filtered. This is used with ProtonVPN and VPN Unlimited.
-	FreeOnly *bool `json:"free_only"`
+	FreeOnly *bool
 	// 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"`
+	PremiumOnly *bool
 	// StreamOnly is true if VPN servers not for streaming should
 	// be filtered. This is used with VPNUnlimited.
-	StreamOnly *bool `json:"stream_only"`
+	StreamOnly *bool
 	// MultiHopOnly is true if VPN servers that are not multihop
 	// should be filtered. This is used with Surfshark.
-	MultiHopOnly *bool `json:"multi_hop_only"`
+	MultiHopOnly *bool

 	// OpenVPN contains settings to select OpenVPN servers
 	// and the final connection.
-	OpenVPN OpenVPNSelection `json:"openvpn"`
+	OpenVPN OpenVPNSelection
 	// Wireguard contains settings to select Wireguard servers
 	// and the final connection.
-	Wireguard WireguardSelection `json:"wireguard"`
+	Wireguard WireguardSelection
 }

 var (
@@ -88,17 +86,12 @@ 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 {
-		return fmt.Errorf("for VPN service provider %s: %w", vpnServiceProvider, err)
+		if errors.Is(err, helpers.ErrNoChoice) {
+			return fmt.Errorf("for VPN service provider %s: %w", vpnServiceProvider, err)
+		}
+		return err // already wrapped error
 	}

 	if *ss.OwnedOnly &&
@@ -125,7 +118,7 @@ func (ss *ServerSelection) validate(vpnServiceProvider string,
 	}

 	if *ss.FreeOnly && *ss.PremiumOnly {
-		return fmt.Errorf("%w", ErrFreePremiumBothSet)
+		return ErrFreePremiumBothSet
 	}

 	if *ss.StreamOnly &&
@@ -167,10 +160,10 @@ func getLocationFilterChoices(vpnServiceProvider string,
 		// // Retro compatibility
 		// TODO v4 remove
 		filterChoices.Regions = append(filterChoices.Regions, validation.SurfsharkRetroLocChoices()...)
-		err := validate.AreAllOneOfCaseInsensitive(ss.Regions, filterChoices.Regions)
-		if err != nil {
-			return models.FilterChoices{}, fmt.Errorf("%w: %w", ErrRegionNotValid, err)
+		if err := helpers.AreAllOneOf(ss.Regions, filterChoices.Regions); err != nil {
+			return models.FilterChoices{}, fmt.Errorf("%w: %s", ErrRegionNotValid, err)
 		}
+		*ss = surfsharkRetroRegion(*ss)
 	}

 	return filterChoices, nil
@@ -179,34 +172,28 @@ 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) {
-	err = validate.AreAllOneOfCaseInsensitive(settings.Countries, filterChoices.Countries)
-	if err != nil {
-		return fmt.Errorf("%w: %w", ErrCountryNotValid, err)
+	if err := helpers.AreAllOneOf(settings.Countries, filterChoices.Countries); err != nil {
+		return fmt.Errorf("%w: %s", ErrCountryNotValid, err)
 	}

-	err = validate.AreAllOneOfCaseInsensitive(settings.Regions, filterChoices.Regions)
-	if err != nil {
-		return fmt.Errorf("%w: %w", ErrRegionNotValid, err)
+	if err := helpers.AreAllOneOf(settings.Regions, filterChoices.Regions); err != nil {
+		return fmt.Errorf("%w: %s", ErrRegionNotValid, err)
 	}

-	err = validate.AreAllOneOfCaseInsensitive(settings.Cities, filterChoices.Cities)
-	if err != nil {
-		return fmt.Errorf("%w: %w", ErrCityNotValid, err)
+	if err := helpers.AreAllOneOf(settings.Cities, filterChoices.Cities); err != nil {
+		return fmt.Errorf("%w: %s", ErrCityNotValid, err)
 	}

-	err = validate.AreAllOneOfCaseInsensitive(settings.ISPs, filterChoices.ISPs)
-	if err != nil {
-		return fmt.Errorf("%w: %w", ErrISPNotValid, err)
+	if err := helpers.AreAllOneOf(settings.ISPs, filterChoices.ISPs); err != nil {
+		return fmt.Errorf("%w: %s", ErrISPNotValid, err)
 	}

-	err = validate.AreAllOneOfCaseInsensitive(settings.Hostnames, filterChoices.Hostnames)
-	if err != nil {
-		return fmt.Errorf("%w: %w", ErrHostnameNotValid, err)
+	if err := helpers.AreAllOneOf(settings.Hostnames, filterChoices.Hostnames); err != nil {
+		return fmt.Errorf("%w: %s", ErrHostnameNotValid, err)
 	}

-	err = validate.AreAllOneOfCaseInsensitive(settings.Names, filterChoices.Names)
-	if err != nil {
-		return fmt.Errorf("%w: %w", ErrNameNotValid, err)
+	if err := helpers.AreAllOneOf(settings.Names, filterChoices.Names); err != nil {
+		return fmt.Errorf("%w: %s", ErrNameNotValid, err)
 	}

 	return nil
@@ -215,71 +202,71 @@ func validateServerFilters(settings ServerSelection, filterChoices models.Filter
 func (ss *ServerSelection) copy() (copied ServerSelection) {
 	return ServerSelection{
 		VPN:          ss.VPN,
-		TargetIP:     ss.TargetIP,
-		Countries:    gosettings.CopySlice(ss.Countries),
-		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),
-		MultiHopOnly: gosettings.CopyPointer(ss.MultiHopOnly),
+		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),
+		PremiumOnly:  helpers.CopyBoolPtr(ss.PremiumOnly),
+		StreamOnly:   helpers.CopyBoolPtr(ss.StreamOnly),
+		MultiHopOnly: helpers.CopyBoolPtr(ss.MultiHopOnly),
 		OpenVPN:      ss.OpenVPN.copy(),
 		Wireguard:    ss.Wireguard.copy(),
 	}
 }

 func (ss *ServerSelection) mergeWith(other ServerSelection) {
-	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.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.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.PremiumOnly = helpers.MergeWithBool(ss.PremiumOnly, other.PremiumOnly)
+	ss.StreamOnly = helpers.MergeWithBool(ss.StreamOnly, other.StreamOnly)
+	ss.MultiHopOnly = helpers.MergeWithBool(ss.MultiHopOnly, other.MultiHopOnly)

 	ss.OpenVPN.mergeWith(other.OpenVPN)
 	ss.Wireguard.mergeWith(other.Wireguard)
 }

 func (ss *ServerSelection) overrideWith(other ServerSelection) {
-	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.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.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.PremiumOnly = helpers.OverrideWithBool(ss.PremiumOnly, other.PremiumOnly)
+	ss.StreamOnly = helpers.OverrideWithBool(ss.StreamOnly, other.StreamOnly)
+	ss.MultiHopOnly = helpers.OverrideWithBool(ss.MultiHopOnly, other.MultiHopOnly)
 	ss.OpenVPN.overrideWith(other.OpenVPN)
 	ss.Wireguard.overrideWith(other.Wireguard)
 }

 func (ss *ServerSelection) setDefaults(vpnProvider string) {
-	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.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.PremiumOnly = helpers.DefaultBool(ss.PremiumOnly, false)
+	ss.StreamOnly = helpers.DefaultBool(ss.StreamOnly, false)
+	ss.MultiHopOnly = helpers.DefaultBool(ss.MultiHopOnly, false)
 	ss.OpenVPN.setDefaults(vpnProvider)
 	ss.Wireguard.setDefaults()
 }
@@ -291,7 +278,7 @@ 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 !ss.TargetIP.IsUnspecified() {
+	if len(ss.TargetIP) > 0 {
 		node.Appendf("Target IP address: %s", ss.TargetIP)
 	}

--- a/internal/configuration/settings/settings.go
+++ b/internal/configuration/settings/settings.go
@@ -3,9 +3,6 @@ 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"
@@ -34,7 +31,7 @@ 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, ipv6Supported bool) (err error) {
+func (s *Settings) Validate(storage Storage) (err error) {
 	nameToValidation := map[string]func() error{
 		"control server":  s.ControlServer.validate,
 		"dns":             s.DNS.validate,
@@ -49,7 +46,7 @@ func (s *Settings) Validate(storage Storage, ipv6Supported bool) (err error) {
 		"version":         s.Version.validate,
 		// Pprof validation done in pprof constructor
 		"VPN": func() error {
-			return s.VPN.Validate(storage, ipv6Supported)
+			return s.VPN.Validate(storage)
 		},
 	}

@@ -98,7 +95,7 @@ func (s *Settings) MergeWith(other Settings) {
 }

 func (s *Settings) OverrideWith(other Settings,
-	storage Storage, ipv6Supported bool) (err error) {
+	storage Storage) (err error) {
 	patchedSettings := s.copy()
 	patchedSettings.ControlServer.overrideWith(other.ControlServer)
 	patchedSettings.DNS.overrideWith(other.DNS)
@@ -113,7 +110,7 @@ func (s *Settings) OverrideWith(other Settings,
 	patchedSettings.Version.overrideWith(other.Version)
 	patchedSettings.VPN.OverrideWith(other.VPN)
 	patchedSettings.Pprof.OverrideWith(other.Pprof)
-	err = patchedSettings.Validate(storage, ipv6Supported)
+	err = patchedSettings.Validate(storage)
 	if err != nil {
 		return err
 	}
@@ -160,24 +157,3 @@ 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
-}
--- a/internal/configuration/settings/settings_test.go
+++ b/internal/configuration/settings/settings_test.go
@@ -34,6 +34,7 @@ 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
@@ -66,7 +67,6 @@ 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:
--- a/internal/configuration/settings/shadowsocks.go
+++ b/internal/configuration/settings/shadowsocks.go
@@ -1,7 +1,7 @@
 package settings

 import (
-	"github.com/qdm12/gosettings"
+	"github.com/qdm12/gluetun/internal/configuration/settings/helpers"
 	"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:  gosettings.CopyPointer(s.Enabled),
+		Enabled:  helpers.CopyBoolPtr(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 = gosettings.MergeWithPointer(s.Enabled, other.Enabled)
-	s.Settings = s.Settings.MergeWith(other.Settings)
+	s.Enabled = helpers.MergeWithBool(s.Enabled, other.Enabled)
+	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 = gosettings.OverrideWithPointer(s.Enabled, other.Enabled)
+	s.Enabled = helpers.OverrideWithBool(s.Enabled, other.Enabled)
 	s.Settings.OverrideWith(other.Settings)
 }

 func (s *Shadowsocks) setDefaults() {
-	s.Enabled = gosettings.DefaultPointer(s.Enabled, false)
+	s.Enabled = helpers.DefaultBool(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", gosettings.BoolToYesNo(s.Enabled))
+	node.Appendf("Enabled: %s", helpers.BoolPtrToYesNo(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", gosettings.ObfuscateKey(*s.Password))
-	node.Appendf("Log addresses: %s", gosettings.BoolToYesNo(s.LogAddresses))
+	node.Appendf("Password: %s", helpers.ObfuscatePassword(*s.Password))
+	node.Appendf("Log addresses: %s", helpers.BoolPtrToYesNo(s.LogAddresses))

 	return node
 }
--- a/internal/configuration/settings/system.go
+++ b/internal/configuration/settings/system.go
@@ -1,7 +1,7 @@
 package settings

 import (
-	"github.com/qdm12/gosettings"
+	"github.com/qdm12/gluetun/internal/configuration/settings/helpers"
 	"github.com/qdm12/gotree"
 )

@@ -19,28 +19,28 @@ func (s System) validate() (err error) {

 func (s *System) copy() (copied System) {
 	return System{
-		PUID:     gosettings.CopyPointer(s.PUID),
-		PGID:     gosettings.CopyPointer(s.PGID),
+		PUID:     helpers.CopyUint32Ptr(s.PUID),
+		PGID:     helpers.CopyUint32Ptr(s.PGID),
 		Timezone: s.Timezone,
 	}
 }

 func (s *System) mergeWith(other System) {
-	s.PUID = gosettings.MergeWithPointer(s.PUID, other.PUID)
-	s.PGID = gosettings.MergeWithPointer(s.PGID, other.PGID)
-	s.Timezone = gosettings.MergeWithString(s.Timezone, other.Timezone)
+	s.PUID = helpers.MergeWithUint32(s.PUID, other.PUID)
+	s.PGID = helpers.MergeWithUint32(s.PGID, other.PGID)
+	s.Timezone = helpers.MergeWithString(s.Timezone, other.Timezone)
 }

 func (s *System) overrideWith(other System) {
-	s.PUID = gosettings.OverrideWithPointer(s.PUID, other.PUID)
-	s.PGID = gosettings.OverrideWithPointer(s.PGID, other.PGID)
-	s.Timezone = gosettings.OverrideWithString(s.Timezone, other.Timezone)
+	s.PUID = helpers.OverrideWithUint32(s.PUID, other.PUID)
+	s.PGID = helpers.OverrideWithUint32(s.PGID, other.PGID)
+	s.Timezone = helpers.OverrideWithString(s.Timezone, other.Timezone)
 }

 func (s *System) setDefaults() {
 	const defaultID = 1000
-	s.PUID = gosettings.DefaultPointer(s.PUID, defaultID)
-	s.PGID = gosettings.DefaultPointer(s.PGID, defaultID)
+	s.PUID = helpers.DefaultUint32(s.PUID, defaultID)
+	s.PGID = helpers.DefaultUint32(s.PGID, defaultID)
 }

 func (s System) String() string {
--- a/internal/configuration/settings/unbound.go
+++ b/internal/configuration/settings/unbound.go
@@ -3,24 +3,25 @@ package settings
 import (
 	"errors"
 	"fmt"
-	"net/netip"
+	"net"

 	"github.com/qdm12/dns/pkg/provider"
 	"github.com/qdm12/dns/pkg/unbound"
-	"github.com/qdm12/gosettings"
+	"github.com/qdm12/gluetun/internal/configuration/settings/helpers"
 	"github.com/qdm12/gotree"
+	"inet.af/netaddr"
 )

 // Unbound is settings for the Unbound program.
 type Unbound struct {
-	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"`
+	Providers             []string
+	Caching               *bool
+	IPv6                  *bool
+	VerbosityLevel        *uint8
+	VerbosityDetailsLevel *uint8
+	ValidationLogLevel    *uint8
+	Username              string
+	Allowed               []netaddr.IPPrefix
 }

 func (u *Unbound) setDefaults() {
@@ -30,26 +31,26 @@ func (u *Unbound) setDefaults() {
 		}
 	}

-	u.Caching = gosettings.DefaultPointer(u.Caching, true)
-	u.IPv6 = gosettings.DefaultPointer(u.IPv6, false)
+	u.Caching = helpers.DefaultBool(u.Caching, true)
+	u.IPv6 = helpers.DefaultBool(u.IPv6, false)

 	const defaultVerbosityLevel = 1
-	u.VerbosityLevel = gosettings.DefaultPointer(u.VerbosityLevel, defaultVerbosityLevel)
+	u.VerbosityLevel = helpers.DefaultUint8(u.VerbosityLevel, defaultVerbosityLevel)

 	const defaultVerbosityDetailsLevel = 0
-	u.VerbosityDetailsLevel = gosettings.DefaultPointer(u.VerbosityDetailsLevel, defaultVerbosityDetailsLevel)
+	u.VerbosityDetailsLevel = helpers.DefaultUint8(u.VerbosityDetailsLevel, defaultVerbosityDetailsLevel)

 	const defaultValidationLogLevel = 0
-	u.ValidationLogLevel = gosettings.DefaultPointer(u.ValidationLogLevel, defaultValidationLogLevel)
+	u.ValidationLogLevel = helpers.DefaultUint8(u.ValidationLogLevel, defaultValidationLogLevel)

 	if u.Allowed == nil {
-		u.Allowed = []netip.Prefix{
-			netip.PrefixFrom(netip.AddrFrom4([4]byte{}), 0),
-			netip.PrefixFrom(netip.AddrFrom16([16]byte{}), 0),
+		u.Allowed = []netaddr.IPPrefix{
+			netaddr.IPPrefixFrom(netaddr.IPv4(0, 0, 0, 0), 0),
+			netaddr.IPPrefixFrom(netaddr.IPv6Raw([16]byte{}), 0),
 		}
 	}

-	u.Username = gosettings.DefaultString(u.Username, "root")
+	u.Username = helpers.DefaultString(u.Username, "root")
 }

 var (
@@ -94,37 +95,37 @@ func (u Unbound) validate() (err error) {

 func (u Unbound) copy() (copied Unbound) {
 	return Unbound{
-		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),
+		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),
 		Username:              u.Username,
-		Allowed:               gosettings.CopySlice(u.Allowed),
+		Allowed:               helpers.CopyIPPrefixSlice(u.Allowed),
 	}
 }

 func (u *Unbound) mergeWith(other Unbound) {
-	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)
+	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)
 }

 func (u *Unbound) overrideWith(other Unbound) {
-	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)
+	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)
 }

 func (u Unbound) ToUnboundFormat() (settings unbound.Settings, err error) {
@@ -148,30 +149,20 @@ func (u Unbound) ToUnboundFormat() (settings unbound.Settings, err error) {
 		VerbosityDetailsLevel: *u.VerbosityDetailsLevel,
 		ValidationLogLevel:    *u.ValidationLogLevel,
 		AccessControl: unbound.AccessControlSettings{
-			Allowed: netipPrefixesToNetaddrIPPrefixes(u.Allowed),
+			Allowed: u.Allowed,
 		},
 		Username: u.Username,
 	}, nil
 }

-var (
-	ErrConvertingNetip = errors.New("converting net.IP to netip.Addr failed")
-)
-
-func (u Unbound) GetFirstPlaintextIPv4() (ipv4 netip.Addr, err error) {
+func (u Unbound) GetFirstPlaintextIPv4() (ipv4 net.IP, err error) {
 	s := u.Providers[0]
 	provider, err := provider.Parse(s)
 	if err != nil {
-		return ipv4, err
+		return nil, err
 	}

-	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
+	return provider.DNS().IPv4[0], nil
 }

 func (u Unbound) String() string {
@@ -186,8 +177,8 @@ func (u Unbound) toLinesNode() (node *gotree.Node) {
 		authServers.Appendf(provider)
 	}

-	node.Appendf("Caching: %s", gosettings.BoolToYesNo(u.Caching))
-	node.Appendf("IPv6: %s", gosettings.BoolToYesNo(u.IPv6))
+	node.Appendf("Caching: %s", helpers.BoolPtrToYesNo(u.Caching))
+	node.Appendf("IPv6: %s", helpers.BoolPtrToYesNo(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)
--- a/internal/configuration/settings/unbound_test.go
+++ b/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: []netip.Prefix{
-			netip.PrefixFrom(netip.AddrFrom4([4]byte{}), 0),
-			netip.PrefixFrom(netip.AddrFrom16([16]byte{}), 0),
+		Allowed: []netaddr.IPPrefix{
+			netaddr.IPPrefixFrom(netaddr.IPv4(0, 0, 0, 0), 0),
+			netaddr.IPPrefixFrom(netaddr.IPv6Raw([16]byte{}), 0),
 		},
 	}

 	b, err := json.Marshal(settings)
 	require.NoError(t, err)

-	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"]}`
+	const expected = `{"Providers":["cloudflare"],"Caching":true,"IPv6":false,` +
+		`"VerbosityLevel":1,"VerbosityDetailsLevel":null,"ValidationLogLevel":0,` +
+		`"Username":"user","Allowed":["0.0.0.0/0","::/0"]}`

 	assert.Equal(t, expected, string(b))

--- a/internal/configuration/settings/updater.go
+++ b/internal/configuration/settings/updater.go
@@ -5,9 +5,8 @@ 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"
 )

@@ -46,9 +45,16 @@ func (u Updater) Validate() (err error) {

 	validProviders := providers.All()
 	for _, provider := range u.Providers {
-		err = validate.IsOneOf(provider, validProviders...)
-		if err != nil {
-			return fmt.Errorf("%w: %w", ErrVPNProviderNameNotValid, err)
+		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))
 		}
 	}

@@ -57,35 +63,35 @@ func (u Updater) Validate() (err error) {

 func (u *Updater) copy() (copied Updater) {
 	return Updater{
-		Period:     gosettings.CopyPointer(u.Period),
+		Period:     helpers.CopyDurationPtr(u.Period),
 		DNSAddress: u.DNSAddress,
 		MinRatio:   u.MinRatio,
-		Providers:  gosettings.CopySlice(u.Providers),
+		Providers:  helpers.CopyStringSlice(u.Providers),
 	}
 }

 // mergeWith merges the other settings into any
 // unset field of the receiver settings object.
 func (u *Updater) mergeWith(other Updater) {
-	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)
+	u.Period = helpers.MergeWithDurationPtr(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)
 }

 // overrideWith overrides fields of the receiver
 // settings object with any field set in the other
 // settings.
 func (u *Updater) overrideWith(other Updater) {
-	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)
+	u.Period = helpers.OverrideWithDurationPtr(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)
 }

 func (u *Updater) SetDefaults(vpnProvider string) {
-	u.Period = gosettings.DefaultPointer(u.Period, 0)
-	u.DNSAddress = gosettings.DefaultString(u.DNSAddress, "1.1.1.1:53")
+	u.Period = helpers.DefaultDurationPtr(u.Period, 0)
+	u.DNSAddress = helpers.DefaultString(u.DNSAddress, "1.1.1.1:53")

 	if u.MinRatio == 0 {
 		const defaultMinRatio = 0.8
--- a/internal/configuration/settings/version.go
+++ b/internal/configuration/settings/version.go
@@ -1,7 +1,7 @@
 package settings

 import (
-	"github.com/qdm12/gosettings"
+	"github.com/qdm12/gluetun/internal/configuration/settings/helpers"
 	"github.com/qdm12/gotree"
 )

@@ -19,25 +19,25 @@ func (v Version) validate() (err error) {

 func (v *Version) copy() (copied Version) {
 	return Version{
-		Enabled: gosettings.CopyPointer(v.Enabled),
+		Enabled: helpers.CopyBoolPtr(v.Enabled),
 	}
 }

 // mergeWith merges the other settings into any
 // unset field of the receiver settings object.
 func (v *Version) mergeWith(other Version) {
-	v.Enabled = gosettings.MergeWithPointer(v.Enabled, other.Enabled)
+	v.Enabled = helpers.MergeWithBool(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 = gosettings.OverrideWithPointer(v.Enabled, other.Enabled)
+	v.Enabled = helpers.OverrideWithBool(v.Enabled, other.Enabled)
 }

 func (v *Version) setDefaults() {
-	v.Enabled = gosettings.DefaultPointer(v.Enabled, true)
+	v.Enabled = helpers.DefaultBool(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", gosettings.BoolToYesNo(v.Enabled))
+	node.Appendf("Enabled: %s", helpers.BoolPtrToYesNo(v.Enabled))

 	return node
 }
--- a/internal/configuration/settings/vpn.go
+++ b/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"
 )

@@ -13,18 +13,19 @@ 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    `json:"type"`
-	Provider  Provider  `json:"provider"`
-	OpenVPN   OpenVPN   `json:"openvpn"`
-	Wireguard Wireguard `json:"wireguard"`
+	Type      string
+	Provider  Provider
+	OpenVPN   OpenVPN
+	Wireguard Wireguard
 }

 // TODO v4 remove pointer for receiver (because of Surfshark).
-func (v *VPN) Validate(storage Storage, ipv6Supported bool) (err error) {
+func (v *VPN) Validate(storage Storage) (err error) {
 	// Validate Type
 	validVPNTypes := []string{vpn.OpenVPN, vpn.Wireguard}
-	if err = validate.IsOneOf(v.Type, validVPNTypes...); err != nil {
-		return fmt.Errorf("%w: %w", ErrVPNTypeNotValid, err)
+	if !helpers.IsOneOf(v.Type, validVPNTypes...) {
+		return fmt.Errorf("%w: %q and can only be one of %s",
+			ErrVPNTypeNotValid, v.Type, strings.Join(validVPNTypes, ", "))
 	}

 	err = v.Provider.validate(v.Type, storage)
@@ -38,7 +39,7 @@ func (v *VPN) Validate(storage Storage, ipv6Supported bool) (err error) {
 			return fmt.Errorf("OpenVPN settings: %w", err)
 		}
 	} else {
-		err := v.Wireguard.validate(*v.Provider.Name, ipv6Supported)
+		err := v.Wireguard.validate(*v.Provider.Name)
 		if err != nil {
 			return fmt.Errorf("Wireguard settings: %w", err)
 		}
@@ -57,24 +58,24 @@ func (v *VPN) Copy() (copied VPN) {
 }

 func (v *VPN) mergeWith(other VPN) {
-	v.Type = gosettings.MergeWithString(v.Type, other.Type)
+	v.Type = helpers.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 = gosettings.OverrideWithString(v.Type, other.Type)
+	v.Type = helpers.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 = gosettings.DefaultString(v.Type, vpn.OpenVPN)
+	v.Type = helpers.DefaultString(v.Type, vpn.OpenVPN)
 	v.Provider.setDefaults()
 	v.OpenVPN.setDefaults(*v.Provider.Name)
-	v.Wireguard.setDefaults(*v.Provider.Name)
+	v.Wireguard.setDefaults()
 }

 func (v VPN) String() string {
--- a/internal/configuration/settings/wireguard.go
+++ b/internal/configuration/settings/wireguard.go
@@ -2,13 +2,11 @@ package settings

 import (
 	"fmt"
-	"net/netip"
+	"net"
 	"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"
 )
@@ -17,43 +15,29 @@ import (
 type Wireguard struct {
 	// PrivateKey is the Wireguard client peer private key.
 	// It cannot be nil in the internal state.
-	PrivateKey *string `json:"private_key"`
+	PrivateKey *string
 	// 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 `json:"pre_shared_key"`
+	PreSharedKey *string
 	// Addresses are the Wireguard interface addresses.
-	Addresses []netip.Prefix `json:"addresses"`
+	Addresses []net.IPNet
 	// Interface is the name of the Wireguard interface
 	// to create. It cannot be the empty string in the
 	// internal state.
-	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"`
+	Interface string
 }

 var regexpInterfaceName = regexp.MustCompile(`^[a-zA-Z0-9_]+$`)

 // Validate validates Wireguard settings.
 // It should only be ran if the VPN type chosen is Wireguard.
-func (w Wireguard) validate(vpnProvider string, ipv6Supported bool) (err error) {
+func (w Wireguard) validate(vpnProvider string) (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
@@ -62,19 +46,13 @@ func (w Wireguard) validate(vpnProvider string, ipv6Supported bool) (err error)

 	// Validate PrivateKey
 	if *w.PrivateKey == "" {
-		return fmt.Errorf("%w", ErrWireguardPrivateKeyNotSet)
+		return ErrWireguardPrivateKeyNotSet
 	}
 	_, err = wgtypes.ParseKey(*w.PrivateKey)
 	if err != nil {
 		return fmt.Errorf("private key is not valid: %w", err)
 	}

-	if vpnProvider == providers.Airvpn {
-		if *w.PreSharedKey == "" {
-			return fmt.Errorf("%w", ErrWireguardPreSharedKeyNotSet)
-		}
-	}
-
 	// Validate PreSharedKey
 	if *w.PreSharedKey != "" { // Note: this is optional
 		_, err = wgtypes.ParseKey(*w.PreSharedKey)
@@ -85,18 +63,13 @@ func (w Wireguard) validate(vpnProvider string, ipv6Supported bool) (err error)

 	// Validate Addresses
 	if len(w.Addresses) == 0 {
-		return fmt.Errorf("%w", ErrWireguardInterfaceAddressNotSet)
+		return ErrWireguardInterfaceAddressNotSet
 	}
 	for i, ipNet := range w.Addresses {
-		if !ipNet.IsValid() {
+		if ipNet.IP == nil || ipNet.Mask == nil {
 			return fmt.Errorf("%w: for address at index %d: %s",
 				ErrWireguardInterfaceAddressNotSet, i, ipNet.String())
 		}
-
-		if !ipv6Supported && ipNet.Addr().Is6() {
-			return fmt.Errorf("%w: address %s",
-				ErrWireguardInterfaceAddressIPv6, ipNet)
-		}
 	}

 	// Validate interface
@@ -105,55 +78,36 @@ func (w Wireguard) validate(vpnProvider string, ipv6Supported bool) (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:     gosettings.CopyPointer(w.PrivateKey),
-		PreSharedKey:   gosettings.CopyPointer(w.PreSharedKey),
-		Addresses:      gosettings.CopySlice(w.Addresses),
-		Interface:      w.Interface,
-		MTU:            w.MTU,
-		Implementation: w.Implementation,
+		PrivateKey:   helpers.CopyStringPtr(w.PrivateKey),
+		PreSharedKey: helpers.CopyStringPtr(w.PreSharedKey),
+		Addresses:    helpers.CopyIPNetSlice(w.Addresses),
+		Interface:    w.Interface,
 	}
 }

 func (w *Wireguard) mergeWith(other Wireguard) {
-	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.Interface = gosettings.MergeWithString(w.Interface, other.Interface)
-	w.MTU = gosettings.MergeWithNumber(w.MTU, other.MTU)
-	w.Implementation = gosettings.MergeWithString(w.Implementation, other.Implementation)
+	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)
 }

 func (w *Wireguard) overrideWith(other Wireguard) {
-	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.Interface = gosettings.OverrideWithString(w.Interface, other.Interface)
-	w.MTU = gosettings.OverrideWithNumber(w.MTU, other.MTU)
-	w.Implementation = gosettings.OverrideWithString(w.Implementation, other.Implementation)
+	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)
 }

-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})
-	}
-	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) setDefaults() {
+	w.PrivateKey = helpers.DefaultStringPtr(w.PrivateKey, "")
+	w.PreSharedKey = helpers.DefaultStringPtr(w.PreSharedKey, "")
+	w.Interface = helpers.DefaultString(w.Interface, "wg0")
 }

 func (w Wireguard) String() string {
@@ -164,12 +118,12 @@ func (w Wireguard) toLinesNode() (node *gotree.Node) {
 	node = gotree.New("Wireguard settings:")

 	if *w.PrivateKey != "" {
-		s := gosettings.ObfuscateKey(*w.PrivateKey)
+		s := helpers.ObfuscateWireguardKey(*w.PrivateKey)
 		node.Appendf("Private key: %s", s)
 	}

 	if *w.PreSharedKey != "" {
-		s := gosettings.ObfuscateKey(*w.PreSharedKey)
+		s := helpers.ObfuscateWireguardKey(*w.PreSharedKey)
 		node.Appendf("Pre-shared key: %s", s)
 	}

@@ -178,12 +132,7 @@ func (w Wireguard) toLinesNode() (node *gotree.Node) {
 		addressesNode.Appendf(address.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)
-	}
+	node.Appendf("Network interface: %s", w.Interface)

 	return node
 }
--- a/internal/configuration/settings/wireguardselection.go
+++ b/internal/configuration/settings/wireguardselection.go
@@ -2,11 +2,10 @@ package settings

 import (
 	"fmt"
-	"net/netip"
+	"net"

+	"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"
 )
@@ -16,20 +15,20 @@ 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 netaddr.IPv4Unspecified(). It can never be the zero value
+	// to the empty net.IP{} slice. It can never be nil
 	// in the internal state.
-	EndpointIP netip.Addr `json:"endpoint_ip"`
+	EndpointIP net.IP
 	// EndpointPort is a the server port to use for the VPN server.
-	// It is optional for VPN providers IVPN, Mullvad, Surfshark
+	// It is optional for VPN providers IVPN, Mullvad
 	// 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 `json:"endpoint_port"`
+	EndpointPort *uint16
 	// PublicKey is the server public key.
 	// It is only used with VPN providers generating Wireguard
 	// configurations specific to each server and user.
-	PublicKey string `json:"public_key"`
+	PublicKey string
 }

 // Validate validates WireguardSelection settings.
@@ -37,12 +36,10 @@ type WireguardSelection struct {
 func (w WireguardSelection) validate(vpnProvider string) (err error) {
 	// Validate EndpointIP
 	switch vpnProvider {
-	case providers.Airvpn, providers.Ivpn, providers.Mullvad,
-		providers.Nordvpn, providers.Surfshark, providers.Windscribe:
-		// endpoint IP addresses are baked in
+	case providers.Ivpn, providers.Mullvad, providers.Windscribe: // endpoint IP addresses are baked in
 	case providers.Custom:
-		if !w.EndpointIP.IsValid() || w.EndpointIP.IsUnspecified() {
-			return fmt.Errorf("%w", ErrWireguardEndpointIPNotSet)
+		if len(w.EndpointIP) == 0 {
+			return ErrWireguardEndpointIPNotSet
 		}
 	default: // Providers not supporting Wireguard
 	}
@@ -52,14 +49,9 @@ func (w WireguardSelection) validate(vpnProvider string) (err error) {
 	// EndpointPort is required
 	case providers.Custom:
 		if *w.EndpointPort == 0 {
-			return fmt.Errorf("%w", ErrWireguardEndpointPortNotSet)
+			return ErrWireguardEndpointPortNotSet
 		}
-	// 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:
+	case providers.Ivpn, providers.Mullvad, providers.Windscribe:
 		// EndpointPort is optional and can be 0
 		if *w.EndpointPort == 0 {
 			break // no custom endpoint port set
@@ -69,31 +61,27 @@ 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}
 		}

-		err = validate.IsOneOf(*w.EndpointPort, allowed...)
-		if err == nil {
+		if helpers.Uint16IsOneOf(*w.EndpointPort, allowed) {
 			break
 		}
-		return fmt.Errorf("%w: for VPN service provider %s: %w",
-			ErrWireguardEndpointPortNotAllowed, vpnProvider, err)
+		return fmt.Errorf("%w: %d for VPN service provider %s; %s",
+			ErrWireguardEndpointPortNotAllowed, w.EndpointPort, vpnProvider,
+			helpers.PortChoicesOrString(allowed))
 	default: // Providers not supporting Wireguard
 	}

 	// Validate PublicKey
 	switch vpnProvider {
-	case providers.Ivpn, providers.Mullvad,
-		providers.Surfshark, providers.Windscribe:
-		// public keys are baked in
+	case providers.Ivpn, providers.Mullvad, providers.Windscribe: // public keys are baked in
 	case providers.Custom:
 		if w.PublicKey == "" {
-			return fmt.Errorf("%w", ErrWireguardPublicKeyNotSet)
+			return ErrWireguardPublicKeyNotSet
 		}
 	default: // Providers not supporting Wireguard
 	}
@@ -110,27 +98,27 @@ func (w WireguardSelection) validate(vpnProvider string) (err error) {

 func (w *WireguardSelection) copy() (copied WireguardSelection) {
 	return WireguardSelection{
-		EndpointIP:   w.EndpointIP,
-		EndpointPort: gosettings.CopyPointer(w.EndpointPort),
+		EndpointIP:   helpers.CopyIP(w.EndpointIP),
+		EndpointPort: helpers.CopyUint16Ptr(w.EndpointPort),
 		PublicKey:    w.PublicKey,
 	}
 }

 func (w *WireguardSelection) mergeWith(other WireguardSelection) {
-	w.EndpointIP = gosettings.MergeWithValidator(w.EndpointIP, other.EndpointIP)
-	w.EndpointPort = gosettings.MergeWithPointer(w.EndpointPort, other.EndpointPort)
-	w.PublicKey = gosettings.MergeWithString(w.PublicKey, other.PublicKey)
+	w.EndpointIP = helpers.MergeWithIP(w.EndpointIP, other.EndpointIP)
+	w.EndpointPort = helpers.MergeWithUint16(w.EndpointPort, other.EndpointPort)
+	w.PublicKey = helpers.MergeWithString(w.PublicKey, other.PublicKey)
 }

 func (w *WireguardSelection) overrideWith(other WireguardSelection) {
-	w.EndpointIP = gosettings.OverrideWithValidator(w.EndpointIP, other.EndpointIP)
-	w.EndpointPort = gosettings.OverrideWithPointer(w.EndpointPort, other.EndpointPort)
-	w.PublicKey = gosettings.OverrideWithString(w.PublicKey, other.PublicKey)
+	w.EndpointIP = helpers.OverrideWithIP(w.EndpointIP, other.EndpointIP)
+	w.EndpointPort = helpers.OverrideWithUint16(w.EndpointPort, other.EndpointPort)
+	w.PublicKey = helpers.OverrideWithString(w.PublicKey, other.PublicKey)
 }

 func (w *WireguardSelection) setDefaults() {
-	w.EndpointIP = gosettings.DefaultValidator(w.EndpointIP, netip.IPv4Unspecified())
-	w.EndpointPort = gosettings.DefaultPointer(w.EndpointPort, 0)
+	w.EndpointIP = helpers.DefaultIP(w.EndpointIP, net.IP{})
+	w.EndpointPort = helpers.DefaultUint16(w.EndpointPort, 0)
 }

 func (w WireguardSelection) String() string {
@@ -140,7 +128,7 @@ func (w WireguardSelection) String() string {
 func (w WireguardSelection) toLinesNode() (node *gotree.Node) {
 	node = gotree.New("Wireguard selection settings:")

-	if !w.EndpointIP.IsUnspecified() {
+	if len(w.EndpointIP) > 0 {
 		node.Appendf("Endpoint IP address: %s", w.EndpointIP)
 	}

--- a/internal/configuration/sources/env/dns.go
+++ b/internal/configuration/sources/env/dns.go
@@ -2,23 +2,23 @@ package env

 import (
 	"fmt"
-	"net/netip"
+	"net"

 	"github.com/qdm12/gluetun/internal/configuration/settings"
 )

-func (s *Source) readDNS() (dns settings.DNS, err error) {
-	dns.ServerAddress, err = s.readDNSServerAddress()
+func (r *Reader) readDNS() (dns settings.DNS, err error) {
+	dns.ServerAddress, err = r.readDNSServerAddress()
 	if err != nil {
 		return dns, err
 	}

-	dns.KeepNameserver, err = s.env.BoolPtr("DNS_KEEP_NAMESERVER")
+	dns.KeepNameserver, err = envToBoolPtr("DNS_KEEP_NAMESERVER")
 	if err != nil {
-		return dns, err
+		return dns, fmt.Errorf("environment variable DNS_KEEP_NAMESERVER: %w", err)
 	}

-	dns.DoT, err = s.readDoT()
+	dns.DoT, err = r.readDoT()
 	if err != nil {
 		return dns, fmt.Errorf("DoT settings: %w", err)
 	}
@@ -26,27 +26,22 @@ func (s *Source) readDNS() (dns settings.DNS, err error) {
 	return dns, 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)
+func (r *Reader) readDNSServerAddress() (address net.IP, err error) {
+	key, s := r.getEnvWithRetro("DNS_ADDRESS", "DNS_PLAINTEXT_ADDRESS")
+	if s == "" {
+		return nil, nil
 	}

-	address, err = s.env.NetipAddr(key)
-	if err != nil {
-		return address, err
+	address = net.ParseIP(s)
+	if address == nil {
+		return nil, fmt.Errorf("environment variable %s: %w: %s", key, ErrIPAddressParse, s)
 	}

 	// TODO remove in v4
-	if address.Unmap().Compare(netip.AddrFrom4([4]byte{127, 0, 0, 1})) != 0 {
-		s.warner.Warn(key + " is set to " + address.String() +
+	if !address.Equal(net.IPv4(127, 0, 0, 1)) { //nolint:gomnd
+		r.warner.Warn(key + " is set to " + s +
 			" 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 serves." +
+			" The default value changed to 127.0.0.1 so it uses the internal DoT server." +
 			" 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.")
 	}
--- a/internal/configuration/sources/env/dnsblacklist.go
+++ b/internal/configuration/sources/env/dnsblacklist.go
@@ -3,62 +3,76 @@ package env
 import (
 	"errors"
 	"fmt"
-	"net/netip"

 	"github.com/qdm12/gluetun/internal/configuration/settings"
-	"github.com/qdm12/gosettings/sources/env"
+	"github.com/qdm12/govalid/binary"
+	"inet.af/netaddr"
 )

-func (s *Source) readDNSBlacklist() (blacklist settings.DNSBlacklist, err error) {
-	blacklist.BlockMalicious, err = s.env.BoolPtr("BLOCK_MALICIOUS")
+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()
 	if err != nil {
 		return blacklist, err
 	}

-	blacklist.BlockSurveillance, err = s.env.BoolPtr("BLOCK_SURVEILLANCE",
-		env.RetroKeys("BLOCK_NSA"))
+	blacklist.BlockAds, err = envToBoolPtr("BLOCK_ADS")
 	if err != nil {
-		return blacklist, err
-	}
-
-	blacklist.BlockAds, err = s.env.BoolPtr("BLOCK_ADS")
-	if err != nil {
-		return blacklist, err
+		return blacklist, fmt.Errorf("environment variable BLOCK_ADS: %w", err)
 	}

 	blacklist.AddBlockedIPs, blacklist.AddBlockedIPPrefixes,
-		err = s.readDoTPrivateAddresses() // TODO v4 split in 2
+		err = readDoTPrivateAddresses() // TODO v4 split in 2
 	if err != nil {
 		return blacklist, err
 	}

-	blacklist.AllowedHosts = s.env.CSV("UNBLOCK") // TODO v4 change name
+	blacklist.AllowedHosts = envToCSV("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 (s *Source) readDoTPrivateAddresses() (ips []netip.Addr,
-	ipPrefixes []netip.Prefix, err error) {
-	privateAddresses := s.env.CSV("DOT_PRIVATE_ADDRESS")
+func readDoTPrivateAddresses() (ips []netaddr.IP,
+	ipPrefixes []netaddr.IPPrefix, err error) {
+	privateAddresses := envToCSV("DOT_PRIVATE_ADDRESS")
 	if len(privateAddresses) == 0 {
 		return nil, nil, nil
 	}

-	ips = make([]netip.Addr, 0, len(privateAddresses))
-	ipPrefixes = make([]netip.Prefix, 0, len(privateAddresses))
+	ips = make([]netaddr.IP, 0, len(privateAddresses))
+	ipPrefixes = make([]netaddr.IPPrefix, 0, len(privateAddresses))

 	for _, privateAddress := range privateAddresses {
-		ip, err := netip.ParseAddr(privateAddress)
+		ip, err := netaddr.ParseIP(privateAddress)
 		if err == nil {
 			ips = append(ips, ip)
 			continue
 		}

-		ipPrefix, err := netip.ParsePrefix(privateAddress)
+		ipPrefix, err := netaddr.ParseIPPrefix(privateAddress)
 		if err == nil {
 			ipPrefixes = append(ipPrefixes, ipPrefix)
 			continue
--- a/internal/configuration/sources/env/dot.go
+++ b/internal/configuration/sources/env/dot.go
@@ -1,26 +1,28 @@
 package env

 import (
+	"fmt"
+
 	"github.com/qdm12/gluetun/internal/configuration/settings"
 )

-func (s *Source) readDoT() (dot settings.DoT, err error) {
-	dot.Enabled, err = s.env.BoolPtr("DOT")
+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()
 	if err != nil {
 		return dot, err
 	}

-	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()
+	dot.Blacklist, err = r.readDNSBlacklist()
 	if err != nil {
 		return dot, err
 	}
--- a/internal/configuration/sources/env/firewall.go
+++ b/internal/configuration/sources/env/firewall.go
@@ -1,36 +1,82 @@
 package env

 import (
+	"errors"
+	"fmt"
+	"net"
+	"strconv"
+
 	"github.com/qdm12/gluetun/internal/configuration/settings"
-	"github.com/qdm12/gosettings/sources/env"
 )

-func (s *Source) readFirewall() (firewall settings.Firewall, err error) {
-	firewall.VPNInputPorts, err = s.env.CSVUint16("FIREWALL_VPN_INPUT_PORTS")
+func (r *Reader) readFirewall() (firewall settings.Firewall, err error) {
+	vpnInputPortStrings := envToCSV("FIREWALL_VPN_INPUT_PORTS")
+	firewall.VPNInputPorts, err = stringsToPorts(vpnInputPortStrings)
 	if err != nil {
-		return firewall, err
+		return firewall, fmt.Errorf("environment variable FIREWALL_VPN_INPUT_PORTS: %w", err)
 	}

-	firewall.InputPorts, err = s.env.CSVUint16("FIREWALL_INPUT_PORTS")
+	inputPortStrings := envToCSV("FIREWALL_INPUT_PORTS")
+	firewall.InputPorts, err = stringsToPorts(inputPortStrings)
 	if err != nil {
-		return firewall, err
+		return firewall, fmt.Errorf("environment variable FIREWALL_INPUT_PORTS: %w", err)
 	}

-	firewall.OutboundSubnets, err = s.env.CSVNetipPrefixes("FIREWALL_OUTBOUND_SUBNETS",
-		env.RetroKeys("EXTRA_SUBNETS"))
+	outboundSubnetsKey, _ := r.getEnvWithRetro("FIREWALL_OUTBOUND_SUBNETS", "EXTRA_SUBNETS")
+	outboundSubnetStrings := envToCSV(outboundSubnetsKey)
+	firewall.OutboundSubnets, err = stringsToIPNets(outboundSubnetStrings)
 	if err != nil {
-		return firewall, err
+		return firewall, fmt.Errorf("environment variable %s: %w", outboundSubnetsKey, err)
 	}

-	firewall.Enabled, err = s.env.BoolPtr("FIREWALL")
+	firewall.Enabled, err = envToBoolPtr("FIREWALL")
 	if err != nil {
-		return firewall, err
+		return firewall, fmt.Errorf("environment variable FIREWALL: %w", err)
 	}

-	firewall.Debug, err = s.env.BoolPtr("FIREWALL_DEBUG")
+	firewall.Debug, err = envToBoolPtr("FIREWALL_DEBUG")
 	if err != nil {
-		return firewall, err
+		return firewall, fmt.Errorf("environment variable FIREWALL_DEBUG: %w", 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
+}
--- a/internal/configuration/sources/env/health.go
+++ b/internal/configuration/sources/env/health.go
@@ -1,35 +1,44 @@
 package env

 import (
+	"fmt"
+	"time"
+
 	"github.com/qdm12/gluetun/internal/configuration/settings"
-	"github.com/qdm12/gosettings/sources/env"
 )

-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"))
+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")

-	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.Initial, err = r.readDurationWithRetro(
 		"HEALTH_VPN_DURATION_INITIAL",
-		env.RetroKeys("HEALTH_OPENVPN_DURATION_INITIAL"))
+		"HEALTH_OPENVPN_DURATION_INITIAL")
 	if err != nil {
 		return health, err
 	}

-	health.VPN.Addition, err = s.env.DurationPtr(
+	health.VPN.Addition, err = r.readDurationWithRetro(
 		"HEALTH_VPN_DURATION_ADDITION",
-		env.RetroKeys("HEALTH_OPENVPN_DURATION_ADDITION"))
+		"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
+}
--- a/internal/configuration/sources/env/helpers.go
+++ b/internal/configuration/sources/env/helpers.go
@@ -3,31 +3,146 @@ package env
 import (
 	"fmt"
 	"os"
+	"strconv"
+	"strings"
+	"time"

-	"github.com/qdm12/gosettings/sources/env"
+	"github.com/qdm12/govalid/binary"
+	"github.com/qdm12/govalid/integer"
 )

+// 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("unsetting environment variable %s: %w", envKey, unsetErr)
+			newErr = fmt.Errorf("cannot unset environment variable %s: %w", envKey, unsetErr)
 		}
 	}
 	return newErr
 }

-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 ""
-}
+func stringPtr(s string) *string { return &s }
+func uint32Ptr(n uint32) *uint32 { return &n }
+func boolPtr(b bool) *bool       { return &b }
--- a/internal/configuration/sources/env/helpers_test.go
+++ b/internal/configuration/sources/env/helpers_test.go
@@ -0,0 +1,22 @@
+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)
+}
--- a/internal/configuration/sources/env/httproxy.go
+++ b/internal/configuration/sources/env/httproxy.go
@@ -4,35 +4,25 @@ import (
 	"fmt"

 	"github.com/qdm12/gluetun/internal/configuration/settings"
-	"github.com/qdm12/gosettings/sources/env"
 	"github.com/qdm12/govalid/binary"
 )

-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))
+func (r *Reader) readHTTPProxy() (httpProxy settings.HTTPProxy, err error) {
+	httpProxy.User = r.readHTTProxyUser()
+	httpProxy.Password = r.readHTTProxyPassword()
+	httpProxy.ListeningAddress = r.readHTTProxyListeningAddress()

-	httpProxy.Password = s.env.Get("HTTPPROXY_PASSWORD",
-		env.RetroKeys("PROXY_PASSWORD", "TINYPROXY_PASSWORD"),
-		env.ForceLowercase(false))
-
-	httpProxy.ListeningAddress, err = s.readHTTProxyListeningAddress()
+	httpProxy.Enabled, err = r.readHTTProxyEnabled()
 	if err != nil {
 		return httpProxy, err
 	}

-	httpProxy.Enabled, err = s.env.BoolPtr("HTTPPROXY", env.RetroKeys("PROXY", "TINYPROXY"))
+	httpProxy.Stealth, err = envToBoolPtr("HTTPPROXY_STEALTH")
 	if err != nil {
-		return httpProxy, err
+		return httpProxy, fmt.Errorf("environment variable HTTPPROXY_STEALTH: %w", err)
 	}

-	httpProxy.Stealth, err = s.env.BoolPtr("HTTPPROXY_STEALTH")
-	if err != nil {
-		return httpProxy, err
-	}
-
-	httpProxy.Log, err = s.readHTTProxyLog()
+	httpProxy.Log, err = r.readHTTProxyLog()
 	if err != nil {
 		return httpProxy, err
 	}
@@ -40,42 +30,59 @@ func (s *Source) readHTTPProxy() (httpProxy settings.HTTPProxy, err error) {
 	return httpProxy, nil
 }

-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
+func (r *Reader) readHTTProxyUser() (user *string) {
+	_, s := r.getEnvWithRetro("HTTPPROXY_USER", "PROXY_USER", "TINYPROXY_USER")
+	if s != "" {
+		return &s
 	}
-
-	// 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
+	return nil
 }

-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 "":
+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 == "" {
 		return nil, nil //nolint:nilnil
-	case currentKey:
-		return s.env.BoolPtr(key)
 	}

-	// 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)
+	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...)
 	if err != nil {
 		return nil, fmt.Errorf("environment variable %s: %w", key, err)
 	}
--- a/internal/configuration/sources/env/log.go
+++ b/internal/configuration/sources/env/log.go
@@ -9,8 +9,8 @@ import (
 	"github.com/qdm12/log"
 )

-func (s *Source) readLog() (log settings.Log, err error) {
-	log.Level, err = s.readLogLevel()
+func readLog() (log settings.Log, err error) {
+	log.Level, err = readLogLevel()
 	if err != nil {
 		return log, err
 	}
@@ -18,14 +18,14 @@ func (s *Source) readLog() (log settings.Log, err error) {
 	return log, nil
 }

-func (s *Source) readLogLevel() (level *log.Level, err error) {
-	value := s.env.String("LOG_LEVEL")
-	if value == "" {
+func readLogLevel() (level *log.Level, err error) {
+	s := getCleanedEnv("LOG_LEVEL")
+	if s == "" {
 		return nil, nil //nolint:nilnil
 	}

 	level = new(log.Level)
-	*level, err = parseLogLevel(value)
+	*level, err = parseLogLevel(s)
 	if err != nil {
 		return nil, fmt.Errorf("environment variable LOG_LEVEL: %w", err)
 	}
--- a/internal/configuration/sources/env/openvpn.go
+++ b/internal/configuration/sources/env/openvpn.go
@@ -1,77 +1,132 @@
 package env

 import (
+	"fmt"
 	"strings"

 	"github.com/qdm12/gluetun/internal/configuration/settings"
-	"github.com/qdm12/gosettings/sources/env"
+	"github.com/qdm12/govalid/binary"
 )

-func (s *Source) readOpenVPN() (
+func (r *Reader) readOpenVPN() (
 	openVPN settings.OpenVPN, err error) {
 	defer func() {
 		err = unsetEnvKeys([]string{"OPENVPN_KEY", "OPENVPN_CERT",
 			"OPENVPN_KEY_PASSPHRASE", "OPENVPN_ENCRYPTED_KEY"}, err)
 	}()

-	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))
+	openVPN.Version = getCleanedEnv("OPENVPN_VERSION")
+	openVPN.User = r.readOpenVPNUser()
+	openVPN.Password = r.readOpenVPNPassword()
+	confFile := getCleanedEnv("OPENVPN_CUSTOM_CONFIG")
+	if confFile != "" {
+		openVPN.ConfFile = &confFile
+	}

-	openVPN.PIAEncPreset = s.readPIAEncryptionPreset()
+	ciphersKey, _ := r.getEnvWithRetro("OPENVPN_CIPHERS", "OPENVPN_CIPHER")
+	openVPN.Ciphers = envToCSV(ciphersKey)

-	openVPN.MSSFix, err = s.env.Uint16Ptr("OPENVPN_MSSFIX")
+	auth := getCleanedEnv("OPENVPN_AUTH")
+	if auth != "" {
+		openVPN.Auth = &auth
+	}
+
+	openVPN.Cert = envToStringPtr("OPENVPN_CERT")
+	openVPN.Key = envToStringPtr("OPENVPN_KEY")
+	openVPN.EncryptedKey = envToStringPtr("OPENVPN_ENCRYPTED_KEY")
+
+	openVPN.KeyPassphrase = r.readOpenVPNKeyPassphrase()
+
+	openVPN.PIAEncPreset = r.readPIAEncryptionPreset()
+
+	openVPN.IPv6, err = envToBoolPtr("OPENVPN_IPV6")
+	if err != nil {
+		return openVPN, fmt.Errorf("environment variable OPENVPN_IPV6: %w", err)
+	}
+
+	openVPN.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()
 	if err != nil {
 		return openVPN, err
 	}

-	openVPN.Interface = s.env.String("VPN_INTERFACE",
-		env.RetroKeys("OPENVPN_INTERFACE"), env.ForceLowercase(false))
-
-	openVPN.ProcessUser, err = s.readOpenVPNProcessUser()
+	openVPN.Verbosity, err = envToIntPtr("OPENVPN_VERBOSITY")
 	if err != nil {
-		return openVPN, err
+		return openVPN, fmt.Errorf("environment variable OPENVPN_VERBOSITY: %w", err)
 	}

-	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)
+	flagsStr := getCleanedEnv("OPENVPN_FLAGS")
+	if flagsStr != "" {
+		openVPN.Flags = strings.Fields(flagsStr)
 	}

 	return openVPN, nil
 }

-func (s *Source) readPIAEncryptionPreset() (presetPtr *string) {
-	return s.env.Get(
-		"PRIVATE_INTERNET_ACCESS_OPENVPN_ENCRYPTION_PRESET",
-		env.RetroKeys("ENCRYPTION", "PIA_ENCRYPTION"))
-}
-
-func (s *Source) readOpenVPNProcessUser() (processUser string, err error) {
-	value, err := s.env.BoolPtr("OPENVPN_ROOT") // Retro-compatibility
-	if err != nil {
-		return "", err
-	} else if value != nil {
-		if *value {
-			return "root", nil
-		}
-		const defaultNonRootUser = "nonrootuser"
-		return defaultNonRootUser, nil
+func (r *Reader) readOpenVPNUser() (user *string) {
+	user = new(string)
+	_, *user = r.getEnvWithRetro("OPENVPN_USER", "USER")
+	if *user == "" {
+		return nil
 	}

-	return s.env.String("OPENVPN_PROCESS_USER"), nil
+	// Remove spaces in user ID to simplify user's life, thanks @JeordyR
+	*user = strings.ReplaceAll(*user, " ", "")
+	return user
+}
+
+func (r *Reader) readOpenVPNPassword() (password *string) {
+	password = new(string)
+	_, *password = r.getEnvWithRetro("OPENVPN_PASSWORD", "PASSWORD")
+	if *password == "" {
+		return nil
+	}
+
+	return password
+}
+
+func (r *Reader) readOpenVPNKeyPassphrase() (passphrase *string) {
+	passphrase = new(string)
+	*passphrase = getCleanedEnv("OPENVPN_KEY_PASSPHRASE")
+	if *passphrase == "" {
+		return nil
+	}
+	return passphrase
+}
+
+func (r *Reader) readPIAEncryptionPreset() (presetPtr *string) {
+	_, preset := r.getEnvWithRetro(
+		"PRIVATE_INTERNET_ACCESS_OPENVPN_ENCRYPTION_PRESET",
+		"PIA_ENCRYPTION", "ENCRYPTION")
+	if preset != "" {
+		return &preset
+	}
+	return nil
+}
+
+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)
+	if err != nil {
+		return "", fmt.Errorf("environment variable %s: %w", key, err)
+	}
+	if root {
+		return "root", nil
+	}
+	const defaultNonRootUser = "nonrootuser"
+	return defaultNonRootUser, nil
 }
--- a/internal/configuration/sources/env/openvpnselection.go
+++ b/internal/configuration/sources/env/openvpnselection.go
@@ -7,50 +7,60 @@ import (

 	"github.com/qdm12/gluetun/internal/configuration/settings"
 	"github.com/qdm12/gluetun/internal/constants"
-	"github.com/qdm12/gosettings/sources/env"
+	"github.com/qdm12/govalid/port"
 )

-func (s *Source) readOpenVPNSelection() (
+func (r *Reader) readOpenVPNSelection() (
 	selection settings.OpenVPNSelection, err error) {
-	selection.ConfFile = s.env.Get("OPENVPN_CUSTOM_CONFIG", env.ForceLowercase(false))
+	confFile := getCleanedEnv("OPENVPN_CUSTOM_CONFIG")
+	if confFile != "" {
+		selection.ConfFile = &confFile
+	}

-	selection.TCP, err = s.readOpenVPNProtocol()
+	selection.TCP, err = r.readOpenVPNProtocol()
 	if err != nil {
 		return selection, err
 	}

-	selection.CustomPort, err = s.env.Uint16Ptr("VPN_ENDPOINT_PORT",
-		env.RetroKeys("PORT", "OPENVPN_PORT"))
+	selection.CustomPort, err = r.readOpenVPNCustomPort()
 	if err != nil {
 		return selection, err
 	}

-	selection.PIAEncPreset = s.readPIAEncryptionPreset()
+	selection.PIAEncPreset = r.readPIAEncryptionPreset()

 	return selection, nil
 }

 var ErrOpenVPNProtocolNotValid = errors.New("OpenVPN protocol is not valid")

-func (s *Source) readOpenVPNProtocol() (tcp *bool, err error) {
-	const currentKey = "OPENVPN_PROTOCOL"
-	envKey := firstKeySet(s.env, "PROTOCOL", currentKey)
-	switch envKey {
+func (r *Reader) readOpenVPNProtocol() (tcp *bool, err error) {
+	envKey, protocol := r.getEnvWithRetro("OPENVPN_PROTOCOL", "PROTOCOL")
+
+	switch strings.ToLower(protocol) {
 	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 ptrTo(false), nil
+		return boolPtr(false), nil
 	case constants.TCP:
-		return ptrTo(true), nil
+		return boolPtr(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
+}
--- a/internal/configuration/sources/env/portforward.go
+++ b/internal/configuration/sources/env/portforward.go
@@ -1,27 +1,27 @@
 package env

 import (
+	"fmt"
+
 	"github.com/qdm12/gluetun/internal/configuration/settings"
-	"github.com/qdm12/gosettings/sources/env"
 )

-func (s *Source) readPortForward() (
+func (r *Reader) readPortForward() (
 	portForwarding settings.PortForwarding, err error) {
-	portForwarding.Enabled, err = s.env.BoolPtr("VPN_PORT_FORWARDING",
-		env.RetroKeys(
-			"PORT_FORWARDING",
-			"PRIVATE_INTERNET_ACCESS_VPN_PORT_FORWARDING",
-		))
+	key, _ := r.getEnvWithRetro(
+		"PRIVATE_INTERNET_ACCESS_VPN_PORT_FORWARDING",
+		"PORT_FORWARDING")
+	portForwarding.Enabled, err = envToBoolPtr(key)
 	if err != nil {
-		return portForwarding, err
+		return portForwarding, fmt.Errorf("environment variable %s: %w", key, err)
 	}

-	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",
-		))
+	_, value := r.getEnvWithRetro(
+		"PRIVATE_INTERNET_ACCESS_VPN_PORT_FORWARDING_STATUS_FILE",
+		"PORT_FORWARDING_STATUS_FILE")
+	if value != "" {
+		portForwarding.Filepath = stringPtr(value)
+	}

 	return portForwarding, nil
 }
--- a/internal/configuration/sources/env/pprof.go
+++ b/internal/configuration/sources/env/pprof.go
@@ -1,26 +1,28 @@
 package env

 import (
+	"fmt"
+
 	"github.com/qdm12/gluetun/internal/pprof"
 )

-func (s *Source) readPprof() (settings pprof.Settings, err error) {
-	settings.Enabled, err = s.env.BoolPtr("PPROF_ENABLED")
+func readPprof() (settings pprof.Settings, err error) {
+	settings.Enabled, err = envToBoolPtr("PPROF_ENABLED")
 	if err != nil {
-		return settings, err
+		return settings, fmt.Errorf("environment variable PPROF_ENABLED: %w", err)
 	}

-	settings.BlockProfileRate, err = s.env.IntPtr("PPROF_BLOCK_PROFILE_RATE")
+	settings.BlockProfileRate, err = envToInt("PPROF_BLOCK_PROFILE_RATE")
 	if err != nil {
-		return settings, err
+		return settings, fmt.Errorf("environment variable PPROF_BLOCK_PROFILE_RATE: %w", err)
 	}

-	settings.MutexProfileRate, err = s.env.IntPtr("PPROF_MUTEX_PROFILE_RATE")
+	settings.MutexProfileRate, err = envToInt("PPROF_MUTEX_PROFILE_RATE")
 	if err != nil {
-		return settings, err
+		return settings, fmt.Errorf("environment variable PPROF_MUTEX_PROFILE_RATE: %w", err)
 	}

-	settings.HTTPServer.Address = s.env.String("PPROF_HTTP_SERVER_ADDRESS")
+	settings.HTTPServer.Address = getCleanedEnv("PPROF_HTTP_SERVER_ADDRESS")

 	return settings, nil
 }
--- a/internal/configuration/sources/env/provider.go
+++ b/internal/configuration/sources/env/provider.go
@@ -7,22 +7,21 @@ 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 (s *Source) readProvider(vpnType string) (provider settings.Provider, err error) {
-	provider.Name = s.readVPNServiceProvider(vpnType)
+func (r *Reader) readProvider(vpnType string) (provider settings.Provider, err error) {
+	provider.Name = r.readVPNServiceProvider(vpnType)
 	var providerName string
 	if provider.Name != nil {
 		providerName = *provider.Name
 	}

-	provider.ServerSelection, err = s.readServerSelection(providerName, vpnType)
+	provider.ServerSelection, err = r.readServerSelection(providerName, vpnType)
 	if err != nil {
 		return provider, fmt.Errorf("server selection: %w", err)
 	}

-	provider.PortForwarding, err = s.readPortForward()
+	provider.PortForwarding, err = r.readPortForward()
 	if err != nil {
 		return provider, fmt.Errorf("port forwarding: %w", err)
 	}
@@ -30,21 +29,17 @@ func (s *Source) readProvider(vpnType string) (provider settings.Provider, err e
 	return provider, nil
 }

-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)
-		}
+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 == "":
 		return nil
+	case s == "pia": // retro compatibility
+		return stringPtr(providers.PrivateInternetAccess)
 	}
-
-	value := *valuePtr
-	value = strings.ToLower(value)
-	if value == "pia" { // retro compatibility
-		return ptrTo(providers.PrivateInternetAccess)
-	}
-
-	return ptrTo(value)
+	return stringPtr(s)
 }
--- a/internal/configuration/sources/env/publicip.go
+++ b/internal/configuration/sources/env/publicip.go
@@ -1,18 +1,42 @@
 package env

 import (
+	"fmt"
+	"time"
+
 	"github.com/qdm12/gluetun/internal/configuration/settings"
-	"github.com/qdm12/gosettings/sources/env"
 )

-func (s *Source) readPublicIP() (publicIP settings.PublicIP, err error) {
-	publicIP.Period, err = s.env.DurationPtr("PUBLICIP_PERIOD")
+func (r *Reader) readPublicIP() (publicIP settings.PublicIP, err error) {
+	publicIP.Period, err = readPublicIPPeriod()
 	if err != nil {
 		return publicIP, err
 	}

-	publicIP.IPFilepath = s.env.Get("PUBLICIP_FILE",
-		env.ForceLowercase(false), env.RetroKeys("IP_STATUS_FILE"))
+	publicIP.IPFilepath = r.readPublicIPFilepath()

 	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
+}
--- a/internal/configuration/sources/env/reader.go
+++ b/internal/configuration/sources/env/reader.go
@@ -1,103 +1,120 @@
 package env

 import (
-	"os"
-
 	"github.com/qdm12/gluetun/internal/configuration/settings"
-	"github.com/qdm12/gosettings/sources/env"
+	"github.com/qdm12/gluetun/internal/configuration/sources"
 )

-type Source struct {
-	env                 env.Env
-	warner              Warner
-	handleDeprecatedKey func(deprecatedKey, newKey string)
+var _ sources.Source = (*Reader)(nil)
+
+type Reader struct {
+	warner Warner
 }

 type Warner interface {
 	Warn(s string)
 }

-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 New(warner Warner) *Reader {
+	return &Reader{
+		warner: warner,
 	}
 }

-func (s *Source) String() string { return "environment variables" }
+func (r *Reader) String() string { return "environment variables" }

-func (s *Source) Read() (settings settings.Settings, err error) {
-	settings.VPN, err = s.readVPN()
+func (r *Reader) Read() (settings settings.Settings, err error) {
+	settings.VPN, err = r.readVPN()
 	if err != nil {
 		return settings, err
 	}

-	settings.Firewall, err = s.readFirewall()
+	settings.Firewall, err = r.readFirewall()
 	if err != nil {
 		return settings, err
 	}

-	settings.System, err = s.readSystem()
+	settings.System, err = r.readSystem()
 	if err != nil {
 		return settings, err
 	}

-	settings.Health, err = s.ReadHealth()
+	settings.Health, err = r.ReadHealth()
 	if err != nil {
 		return settings, err
 	}

-	settings.HTTPProxy, err = s.readHTTPProxy()
+	settings.HTTPProxy, err = r.readHTTPProxy()
 	if err != nil {
 		return settings, err
 	}

-	settings.Log, err = s.readLog()
+	settings.Log, err = readLog()
 	if err != nil {
 		return settings, err
 	}

-	settings.PublicIP, err = s.readPublicIP()
+	settings.PublicIP, err = r.readPublicIP()
 	if err != nil {
 		return settings, err
 	}

-	settings.Updater, err = s.readUpdater()
+	settings.Updater, err = readUpdater()
 	if err != nil {
 		return settings, err
 	}

-	settings.Version, err = s.readVersion()
+	settings.Version, err = readVersion()
 	if err != nil {
 		return settings, err
 	}

-	settings.Shadowsocks, err = s.readShadowsocks()
+	settings.Shadowsocks, err = r.readShadowsocks()
 	if err != nil {
 		return settings, err
 	}

-	settings.DNS, err = s.readDNS()
+	settings.DNS, err = r.readDNS()
 	if err != nil {
 		return settings, err
 	}

-	settings.ControlServer, err = s.readControlServer()
+	settings.ControlServer, err = r.readControlServer()
 	if err != nil {
 		return settings, err
 	}

-	settings.Pprof, err = s.readPprof()
+	settings.Pprof, err = 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)
+}
--- a/internal/configuration/sources/env/server.go
+++ b/internal/configuration/sources/env/server.go
@@ -1,31 +1,48 @@
 package env

 import (
+	"fmt"
+
 	"github.com/qdm12/gluetun/internal/configuration/settings"
+	"github.com/qdm12/govalid/binary"
 )

-func (s *Source) readControlServer() (controlServer settings.ControlServer, err error) {
-	controlServer.Log, err = s.env.BoolPtr("HTTP_CONTROL_SERVER_LOG")
+func (r *Reader) readControlServer() (controlServer settings.ControlServer, err error) {
+	controlServer.Log, err = readControlServerLog()
 	if err != nil {
 		return controlServer, err
 	}

-	controlServer.Address = s.readControlServerAddress()
+	controlServer.Address = r.readControlServerAddress()

 	return controlServer, nil
 }

-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)
+func readControlServerLog() (enabled *bool, err error) {
+	s := getCleanedEnv("HTTP_CONTROL_SERVER_LOG")
+	if s == "" {
+		return nil, nil //nolint:nilnil
 	}

-	s.handleDeprecatedKey(key, currentKey)
-	value := s.env.Get("CONTROL_SERVER_ADDRESS")
-	if value == nil {
+	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 == "" {
 		return nil
 	}
-	return ptrTo(":" + *value)
+
+	if key == "HTTP_CONTROL_SERVER_ADDRESS" {
+		return &s
+	}
+
+	address = new(string)
+	*address = ":" + s
+	return address
 }
--- a/internal/configuration/sources/env/serverselection.go
+++ b/internal/configuration/sources/env/serverselection.go
@@ -2,77 +2,105 @@ 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"
 )

-func (s *Source) readServerSelection(vpnProvider, vpnType string) (
+var (
+	ErrServerNumberNotValid = errors.New("server number is not valid")
+)
+
+func (r *Reader) readServerSelection(vpnProvider, vpnType string) (
 	ss settings.ServerSelection, err error) {
 	ss.VPN = vpnType

-	ss.TargetIP, err = s.env.NetipAddr("VPN_ENDPOINT_IP",
-		env.RetroKeys("OPENVPN_TARGET_IP"))
+	ss.TargetIP, err = r.readOpenVPNTargetIP()
 	if err != nil {
 		return ss, err
 	}

-	ss.Countries = s.env.CSV("SERVER_COUNTRIES", env.RetroKeys("COUNTRY"))
+	countriesKey, _ := r.getEnvWithRetro("SERVER_COUNTRIES", "COUNTRY")
+	ss.Countries = envToCSV(countriesKey)
 	if vpnProvider == providers.Cyberghost && len(ss.Countries) == 0 {
 		// Retro-compatibility for Cyberghost using the REGION variable
-		ss.Countries = s.env.CSV("REGION")
+		ss.Countries = envToCSV("REGION")
 		if len(ss.Countries) > 0 {
-			s.handleDeprecatedKey("REGION", "SERVER_COUNTRIES")
+			r.onRetroActive("REGION", "SERVER_COUNTRIES")
 		}
 	}

-	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")
-	if err != nil {
-		return ss, err
+	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
 	}

 	// Mullvad only
-	ss.OwnedOnly, err = s.env.BoolPtr("OWNED_ONLY", env.RetroKeys("OWNED"))
+	ss.OwnedOnly, err = r.readOwnedOnly()
 	if err != nil {
 		return ss, err
 	}

 	// VPNUnlimited and ProtonVPN only
-	ss.FreeOnly, err = s.env.BoolPtr("FREE_ONLY")
+	ss.FreeOnly, err = envToBoolPtr("FREE_ONLY")
 	if err != nil {
-		return ss, err
+		return ss, fmt.Errorf("environment variable FREE_ONLY: %w", err)
 	}

 	// VPNSecure only
-	ss.PremiumOnly, err = s.env.BoolPtr("PREMIUM_ONLY")
+	ss.PremiumOnly, err = envToBoolPtr("PREMIUM_ONLY")
 	if err != nil {
-		return ss, err
+		return ss, fmt.Errorf("environment variable PREMIUM_ONLY: %w", err)
 	}

 	// VPNUnlimited only
-	ss.MultiHopOnly, err = s.env.BoolPtr("MULTIHOP_ONLY")
+	ss.MultiHopOnly, err = envToBoolPtr("MULTIHOP_ONLY")
 	if err != nil {
-		return ss, err
+		return ss, fmt.Errorf("environment variable MULTIHOP_ONLY: %w", err)
 	}

 	// VPNUnlimited only
-	ss.MultiHopOnly, err = s.env.BoolPtr("STREAM_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()
 	if err != nil {
 		return ss, err
 	}

-	ss.OpenVPN, err = s.readOpenVPNSelection()
-	if err != nil {
-		return ss, err
-	}
-
-	ss.Wireguard, err = s.readWireguardSelection()
+	ss.Wireguard, err = r.readWireguardSelection()
 	if err != nil {
 		return ss, err
 	}
@@ -83,3 +111,27 @@ func (s *Source) 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
+}
--- a/internal/configuration/sources/env/shadowsocks.go
+++ b/internal/configuration/sources/env/shadowsocks.go
@@ -2,41 +2,43 @@ package env

 import (
 	"fmt"
+	"strings"

 	"github.com/qdm12/gluetun/internal/configuration/settings"
-	"github.com/qdm12/gosettings/sources/env"
 )

-func (s *Source) readShadowsocks() (shadowsocks settings.Shadowsocks, err error) {
-	shadowsocks.Enabled, err = s.env.BoolPtr("SHADOWSOCKS")
+func (r *Reader) readShadowsocks() (shadowsocks settings.Shadowsocks, err error) {
+	shadowsocks.Enabled, err = envToBoolPtr("SHADOWSOCKS")
 	if err != nil {
-		return shadowsocks, err
+		return shadowsocks, fmt.Errorf("environment variable SHADOWSOCKS: %w", err)
 	}

-	shadowsocks.Address, err = s.readShadowsocksAddress()
+	shadowsocks.Address = r.readShadowsocksAddress()
+	shadowsocks.LogAddresses, err = envToBoolPtr("SHADOWSOCKS_LOG")
 	if err != nil {
-		return shadowsocks, err
+		return shadowsocks, fmt.Errorf("environment variable SHADOWSOCKS_LOG: %w", err)
 	}
-	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))
+	shadowsocks.CipherName = r.readShadowsocksCipher()
+	shadowsocks.Password = envToStringPtr("SHADOWSOCKS_PASSWORD")

 	return shadowsocks, nil
 }

-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
+func (r *Reader) readShadowsocksAddress() (address string) {
+	key, value := r.getEnvWithRetro("SHADOWSOCKS_LISTENING_ADDRESS", "SHADOWSOCKS_PORT")
+	if value == "" {
+		return ""
 	}

-	return s.env.Get(currentKey), 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)
 }
--- a/internal/configuration/sources/env/system.go
+++ b/internal/configuration/sources/env/system.go
@@ -1,22 +1,55 @@
 package env

 import (
+	"errors"
+	"fmt"
+	"strconv"
+
 	"github.com/qdm12/gluetun/internal/configuration/settings"
-	"github.com/qdm12/gosettings/sources/env"
 )

-func (s *Source) readSystem() (system settings.System, err error) {
-	system.PUID, err = s.env.Uint32Ptr("PUID", env.RetroKeys("UID"))
+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")
 	if err != nil {
 		return system, err
 	}

-	system.PGID, err = s.env.Uint32Ptr("PGID", env.RetroKeys("GID"))
+	system.PGID, err = r.readID("PGID", "GID")
 	if err != nil {
 		return system, err
 	}

-	system.Timezone = s.env.String("TZ")
+	system.Timezone = getCleanedEnv("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
+}
--- a/internal/configuration/sources/env/system_test.go
+++ b/internal/configuration/sources/env/system_test.go
@@ -0,0 +1,88 @@
+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)
+		})
+	}
+}
--- a/internal/configuration/sources/env/unbound.go
+++ b/internal/configuration/sources/env/unbound.go
@@ -1,35 +1,37 @@
 package env

 import (
+	"fmt"
+
 	"github.com/qdm12/gluetun/internal/configuration/settings"
 )

-func (s *Source) readUnbound() (unbound settings.Unbound, err error) {
-	unbound.Providers = s.env.CSV("DOT_PROVIDERS")
+func readUnbound() (unbound settings.Unbound, err error) {
+	unbound.Providers = envToCSV("DOT_PROVIDERS")

-	unbound.Caching, err = s.env.BoolPtr("DOT_CACHING")
+	unbound.Caching, err = envToBoolPtr("DOT_CACHING")
 	if err != nil {
-		return unbound, err
+		return unbound, fmt.Errorf("environment variable DOT_CACHING: %w", err)
 	}

-	unbound.IPv6, err = s.env.BoolPtr("DOT_IPV6")
+	unbound.IPv6, err = envToBoolPtr("DOT_IPV6")
 	if err != nil {
-		return unbound, err
+		return unbound, fmt.Errorf("environment variable DOT_IPV6: %w", err)
 	}

-	unbound.VerbosityLevel, err = s.env.Uint8Ptr("DOT_VERBOSITY")
+	unbound.VerbosityLevel, err = envToUint8Ptr("DOT_VERBOSITY")
 	if err != nil {
-		return unbound, err
+		return unbound, fmt.Errorf("environment variable DOT_VERBOSITY: %w", err)
 	}

-	unbound.VerbosityDetailsLevel, err = s.env.Uint8Ptr("DOT_VERBOSITY_DETAILS")
+	unbound.VerbosityDetailsLevel, err = envToUint8Ptr("DOT_VERBOSITY_DETAILS")
 	if err != nil {
-		return unbound, err
+		return unbound, fmt.Errorf("environment variable DOT_VERBOSITY_DETAILS: %w", err)
 	}

-	unbound.ValidationLogLevel, err = s.env.Uint8Ptr("DOT_VALIDATION_LOGLEVEL")
+	unbound.ValidationLogLevel, err = envToUint8Ptr("DOT_VALIDATION_LOGLEVEL")
 	if err != nil {
-		return unbound, err
+		return unbound, fmt.Errorf("environment variable DOT_VALIDATION_LOGLEVEL: %w", err)
 	}

 	return unbound, nil
--- a/internal/configuration/sources/env/updater.go
+++ b/internal/configuration/sources/env/updater.go
@@ -1,11 +1,14 @@
 package env

 import (
+	"fmt"
+	"time"
+
 	"github.com/qdm12/gluetun/internal/configuration/settings"
 )

-func (s *Source) readUpdater() (updater settings.Updater, err error) {
-	updater.Period, err = s.env.DurationPtr("UPDATER_PERIOD")
+func readUpdater() (updater settings.Updater, err error) {
+	updater.Period, err = readUpdaterPeriod()
 	if err != nil {
 		return updater, err
 	}
@@ -15,16 +18,29 @@ func (s *Source) readUpdater() (updater settings.Updater, err error) {
 		return updater, err
 	}

-	updater.MinRatio, err = s.env.Float64("UPDATER_MIN_RATIO")
+	updater.MinRatio, err = envToFloat64("UPDATER_MIN_RATIO")
 	if err != nil {
-		return updater, err
+		return updater, fmt.Errorf("environment variable UPDATER_MIN_RATIO: %w", err)
 	}

-	updater.Providers = s.env.CSV("UPDATER_VPN_SERVICE_PROVIDERS")
+	updater.Providers = envToCSV("UPDATER_VPN_SERVICE_PROVIDERS")

 	return updater, nil
 }

+func readUpdaterPeriod() (period *time.Duration, err error) {
+	s := getCleanedEnv("UPDATER_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 UPDATER_PERIOD: %w", err)
+	}
+	return period, nil
+}
+
 func readUpdaterDNSAddress() (address string, err error) {
 	// TODO this is currently using Cloudflare in
 	// plaintext to not be blocked by DNS over TLS by default.
--- a/internal/configuration/sources/env/version.go
+++ b/internal/configuration/sources/env/version.go
@@ -1,14 +1,32 @@
 package env

 import (
+	"fmt"
+
 	"github.com/qdm12/gluetun/internal/configuration/settings"
+	"github.com/qdm12/govalid/binary"
 )

-func (s *Source) readVersion() (version settings.Version, err error) {
-	version.Enabled, err = s.env.BoolPtr("VERSION_INFORMATION")
+func readVersion() (version settings.Version, err error) {
+	version.Enabled, err = readVersionEnabled()
 	if err != nil {
 		return version, err
 	}

 	return version, nil
 }
+
+func readVersionEnabled() (enabled *bool, err error) {
+	s := getCleanedEnv("VERSION_INFORMATION")
+	if s == "" {
+		return nil, nil //nolint:nilnil
+	}
+
+	enabled = new(bool)
+	*enabled, err = binary.Validate(s)
+	if err != nil {
+		return nil, fmt.Errorf("environment variable VERSION_INFORMATION: %w", err)
+	}
+
+	return enabled, nil
+}
--- a/internal/configuration/sources/env/vpn.go
+++ b/internal/configuration/sources/env/vpn.go
@@ -2,24 +2,25 @@ package env

 import (
 	"fmt"
+	"strings"

 	"github.com/qdm12/gluetun/internal/configuration/settings"
 )

-func (s *Source) readVPN() (vpn settings.VPN, err error) {
-	vpn.Type = s.env.String("VPN_TYPE")
+func (r *Reader) readVPN() (vpn settings.VPN, err error) {
+	vpn.Type = strings.ToLower(getCleanedEnv("VPN_TYPE"))

-	vpn.Provider, err = s.readProvider(vpn.Type)
+	vpn.Provider, err = r.readProvider(vpn.Type)
 	if err != nil {
 		return vpn, fmt.Errorf("VPN provider: %w", err)
 	}

-	vpn.OpenVPN, err = s.readOpenVPN()
+	vpn.OpenVPN, err = r.readOpenVPN()
 	if err != nil {
 		return vpn, fmt.Errorf("OpenVPN: %w", err)
 	}

-	vpn.Wireguard, err = s.readWireguard()
+	vpn.Wireguard, err = r.readWireguard()
 	if err != nil {
 		return vpn, fmt.Errorf("wireguard: %w", err)
 	}
--- a/internal/configuration/sources/env/wireguard.go
+++ b/internal/configuration/sources/env/wireguard.go
@@ -1,29 +1,43 @@
 package env

 import (
+	"fmt"
+	"net"
+	"strings"
+
 	"github.com/qdm12/gluetun/internal/configuration/settings"
-	"github.com/qdm12/gosettings/sources/env"
 )

-func (s *Source) readWireguard() (wireguard settings.Wireguard, err error) {
+func (r *Reader) readWireguard() (wireguard settings.Wireguard, err error) {
 	defer func() {
 		err = unsetEnvKeys([]string{"WIREGUARD_PRIVATE_KEY", "WIREGUARD_PRESHARED_KEY"}, err)
 	}()
-	wireguard.PrivateKey = s.env.Get("WIREGUARD_PRIVATE_KEY", env.ForceLowercase(false))
-	wireguard.PreSharedKey = s.env.Get("WIREGUARD_PRESHARED_KEY", env.ForceLowercase(false))
-	wireguard.Interface = s.env.String("VPN_INTERFACE",
-		env.RetroKeys("WIREGUARD_INTERFACE"), env.ForceLowercase(false))
-	wireguard.Implementation = s.env.String("WIREGUARD_IMPLEMENTATION")
-	wireguard.Addresses, err = s.env.CSVNetipPrefixes("WIREGUARD_ADDRESSES",
-		env.RetroKeys("WIREGUARD_ADDRESS"))
+	wireguard.PrivateKey = envToStringPtr("WIREGUARD_PRIVATE_KEY")
+	wireguard.PreSharedKey = envToStringPtr("WIREGUARD_PRESHARED_KEY")
+	_, wireguard.Interface = r.getEnvWithRetro("VPN_INTERFACE", "WIREGUARD_INTERFACE")
+	wireguard.Addresses, err = r.readWireguardAddresses()
 	if err != nil {
 		return wireguard, err // already wrapped
 	}
-	mtuPtr, err := s.env.Uint16Ptr("WIREGUARD_MTU")
-	if err != nil {
-		return wireguard, err
-	} else if mtuPtr != nil {
-		wireguard.MTU = *mtuPtr
-	}
 	return wireguard, nil
 }
+
+func (r *Reader) readWireguardAddresses() (addresses []net.IPNet, err error) {
+	key, addressesCSV := r.getEnvWithRetro("WIREGUARD_ADDRESSES", "WIREGUARD_ADDRESS")
+	if addressesCSV == "" {
+		return nil, nil
+	}
+
+	addressStrings := strings.Split(addressesCSV, ",")
+	addresses = make([]net.IPNet, len(addressStrings))
+	for i, addressString := range addressStrings {
+		ip, ipNet, err := net.ParseCIDR(addressString)
+		if err != nil {
+			return nil, fmt.Errorf("environment variable %s: %w", key, err)
+		}
+		ipNet.IP = ip
+		addresses[i] = *ipNet
+	}
+
+	return addresses, nil
+}
--- a/internal/configuration/sources/env/wireguardselection.go
+++ b/internal/configuration/sources/env/wireguardselection.go
@@ -1,23 +1,59 @@
 package env

 import (
+	"errors"
+	"fmt"
+	"net"
+
 	"github.com/qdm12/gluetun/internal/configuration/settings"
-	"github.com/qdm12/gosettings/sources/env"
+	"github.com/qdm12/govalid/port"
 )

-func (s *Source) readWireguardSelection() (
+func (r *Reader) readWireguardSelection() (
 	selection settings.WireguardSelection, err error) {
-	selection.EndpointIP, err = s.env.NetipAddr("VPN_ENDPOINT_IP", env.RetroKeys("WIREGUARD_ENDPOINT_IP"))
+	selection.EndpointIP, err = r.readWireguardEndpointIP()
 	if err != nil {
 		return selection, err
 	}

-	selection.EndpointPort, err = s.env.Uint16Ptr("VPN_ENDPOINT_PORT", env.RetroKeys("WIREGUARD_ENDPOINT_PORT"))
+	selection.EndpointPort, err = r.readWireguardCustomPort()
 	if err != nil {
 		return selection, err
 	}

-	selection.PublicKey = s.env.String("WIREGUARD_PUBLIC_KEY", env.ForceLowercase(false))
+	selection.PublicKey = getCleanedEnv("WIREGUARD_PUBLIC_KEY")

 	return selection, nil
 }
+
+var ErrIPAddressParse = errors.New("cannot parse IP address")
+
+func (r *Reader) readWireguardEndpointIP() (endpointIP net.IP, err error) {
+	key, s := r.getEnvWithRetro("VPN_ENDPOINT_IP", "WIREGUARD_ENDPOINT_IP")
+	if s == "" {
+		return nil, nil
+	}
+
+	endpointIP = net.ParseIP(s)
+	if endpointIP == nil {
+		return nil, fmt.Errorf("environment variable %s: %w: %s",
+			key, ErrIPAddressParse, s)
+	}
+
+	return endpointIP, nil
+}
+
+func (r *Reader) readWireguardCustomPort() (customPort *uint16, err error) {
+	key, s := r.getEnvWithRetro("VPN_ENDPOINT_PORT", "WIREGUARD_ENDPOINT_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
+}
--- a/internal/configuration/sources/files/health.go
+++ b/internal/configuration/sources/files/health.go
@@ -2,4 +2,4 @@ package files

 import "github.com/qdm12/gluetun/internal/configuration/settings"

-func (s *Source) ReadHealth() (settings settings.Health, err error) { return settings, nil }
+func (r *Reader) ReadHealth() (settings settings.Health, err error) { return settings, nil }
--- a/internal/configuration/sources/files/openvpn.go
+++ b/internal/configuration/sources/files/openvpn.go
@@ -14,7 +14,7 @@ const (
 	openVPNEncryptedKey          = "/gluetun/openvpn_encrypted_key"
 )

-func (s *Source) readOpenVPN() (settings settings.OpenVPN, err error) {
+func (r *Reader) readOpenVPN() (settings settings.OpenVPN, err error) {
 	settings.Key, err = readPEMFile(OpenVPNClientKeyPath)
 	if err != nil {
 		return settings, fmt.Errorf("client key: %w", err)
--- a/internal/configuration/sources/files/reader.go
+++ b/internal/configuration/sources/files/reader.go
@@ -2,23 +2,26 @@ package files

 import (
 	"github.com/qdm12/gluetun/internal/configuration/settings"
+	"github.com/qdm12/gluetun/internal/configuration/sources"
 )

-type Source struct{}
+var _ sources.Source = (*Reader)(nil)

-func New() *Source {
-	return &Source{}
+type Reader struct{}
+
+func New() *Reader {
+	return &Reader{}
 }

-func (s *Source) String() string { return "files" }
+func (r *Reader) String() string { return "files" }

-func (s *Source) Read() (settings settings.Settings, err error) {
-	settings.VPN, err = s.readVPN()
+func (r *Reader) Read() (settings settings.Settings, err error) {
+	settings.VPN, err = r.readVPN()
 	if err != nil {
 		return settings, err
 	}

-	settings.System, err = s.readSystem()
+	settings.System, err = r.readSystem()
 	if err != nil {
 		return settings, err
 	}
--- a/internal/configuration/sources/files/system.go
+++ b/internal/configuration/sources/files/system.go
@@ -4,7 +4,7 @@ import (
 	"github.com/qdm12/gluetun/internal/configuration/settings"
 )

-func (s *Source) readSystem() (system settings.System, err error) {
+func (r *Reader) readSystem() (system settings.System, err error) {
 	// TODO timezone from /etc/localtime
 	return system, nil
 }
--- a/internal/configuration/sources/files/vpn.go
+++ b/internal/configuration/sources/files/vpn.go
@@ -6,8 +6,8 @@ import (
 	"github.com/qdm12/gluetun/internal/configuration/settings"
 )

-func (s *Source) readVPN() (vpn settings.VPN, err error) {
-	vpn.OpenVPN, err = s.readOpenVPN()
+func (r *Reader) readVPN() (vpn settings.VPN, err error) {
+	vpn.OpenVPN, err = r.readOpenVPN()
 	if err != nil {
 		return vpn, fmt.Errorf("OpenVPN: %w", err)
 	}
--- a/internal/configuration/sources/merge/reader.go
+++ b/internal/configuration/sources/merge/reader.go
@@ -1,32 +1,29 @@
-package merge
+package mux

 import (
 	"fmt"
 	"strings"

 	"github.com/qdm12/gluetun/internal/configuration/settings"
+	"github.com/qdm12/gluetun/internal/configuration/sources"
 )

-type ConfigSource interface {
-	Read() (settings settings.Settings, err error)
-	ReadHealth() (settings settings.Health, err error)
-	String() string
+var _ sources.Source = (*Reader)(nil)
+
+type Reader struct {
+	sources []sources.Source
 }

-type Source struct {
-	sources []ConfigSource
-}
-
-func New(sources ...ConfigSource) *Source {
-	return &Source{
+func New(sources ...sources.Source) *Reader {
+	return &Reader{
 		sources: sources,
 	}
 }

-func (s *Source) String() string {
-	sources := make([]string, len(s.sources))
-	for i := range s.sources {
-		sources[i] = s.sources[i].String()
+func (r *Reader) String() string {
+	sources := make([]string, len(r.sources))
+	for i := range r.sources {
+		sources[i] = r.sources[i].String()
 	}
 	return strings.Join(sources, ", ")
 }
@@ -34,8 +31,8 @@ func (s *Source) String() string {
 // Read reads the settings for each source, merging unset fields
 // with field set by the next source.
 // It then set defaults to remaining unset fields.
-func (s *Source) Read() (settings settings.Settings, err error) {
-	for _, source := range s.sources {
+func (r *Reader) Read() (settings settings.Settings, err error) {
+	for _, source := range r.sources {
 		settingsFromSource, err := source.Read()
 		if err != nil {
 			return settings, fmt.Errorf("reading from %s: %w", source, err)
@@ -50,8 +47,8 @@ func (s *Source) Read() (settings settings.Settings, err error) {
 // with field set by the next source.
 // It then set defaults to remaining unset fields, and validate
 // all the fields.
-func (s *Source) ReadHealth() (settings settings.Health, err error) {
-	for _, source := range s.sources {
+func (r *Reader) ReadHealth() (settings settings.Health, err error) {
+	for _, source := range r.sources {
 		settingsFromSource, err := source.ReadHealth()
 		if err != nil {
 			return settings, fmt.Errorf("reading from %s: %w", source, err)
--- a/internal/configuration/sources/secrets/health.go
+++ b/internal/configuration/sources/secrets/health.go
@@ -2,4 +2,4 @@ package secrets

 import "github.com/qdm12/gluetun/internal/configuration/settings"

-func (s *Source) ReadHealth() (settings settings.Health, err error) { return settings, nil }
+func (r *Reader) ReadHealth() (settings settings.Health, err error) { return settings, nil }
--- a/internal/configuration/sources/secrets/helpers.go
+++ b/internal/configuration/sources/secrets/helpers.go
@@ -2,24 +2,35 @@ package secrets

 import (
 	"fmt"
+	"os"
+	"strings"

 	"github.com/qdm12/gluetun/internal/configuration/sources/files"
 	"github.com/qdm12/gluetun/internal/openvpn/extract"
-	"github.com/qdm12/gosettings/sources/env"
 )

-func (s *Source) readSecretFileAsStringPtr(secretPathEnvKey, defaultSecretPath string) (
+// 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 readSecretFileAsStringPtr(secretPathEnvKey, defaultSecretPath string) (
 	stringPtr *string, err error) {
-	path := s.env.String(secretPathEnvKey, env.ForceLowercase(false))
+	path := getCleanedEnv(secretPathEnvKey)
 	if path == "" {
 		path = defaultSecretPath
 	}
 	return files.ReadFromFile(path)
 }

-func (s *Source) readPEMSecretFile(secretPathEnvKey, defaultSecretPath string) (
+func readPEMSecretFile(secretPathEnvKey, defaultSecretPath string) (
 	base64Ptr *string, err error) {
-	pemData, err := s.readSecretFileAsStringPtr(secretPathEnvKey, defaultSecretPath)
+	pemData, err := readSecretFileAsStringPtr(secretPathEnvKey, defaultSecretPath)
 	if err != nil {
 		return nil, fmt.Errorf("reading secret file: %w", err)
 	}
--- a/internal/configuration/sources/secrets/helpers_test.go
+++ b/internal/configuration/sources/secrets/helpers_test.go
@@ -1,92 +0,0 @@
-package secrets
-
-import (
-	"os"
-	"path/filepath"
-	"testing"
-
-	"github.com/qdm12/gosettings/sources/env"
-	"github.com/stretchr/testify/assert"
-	"github.com/stretchr/testify/require"
-)
-
-func ptrTo[T any](value T) *T { return &value }
-
-func Test_readSecretFileAsStringPtr(t *testing.T) {
-	t.Parallel()
-
-	testCases := map[string]struct {
-		source                func(tempDir string) Source
-		secretPathEnvKey      string
-		defaultSecretFileName string
-		setupFile             func(tempDir string) error
-		stringPtr             *string
-		errWrapped            error
-		errMessage            string
-	}{
-		"no_secret_file": {
-			defaultSecretFileName: "default_secret_file",
-			secretPathEnvKey:      "SECRET_FILE",
-		},
-		"empty_secret_file": {
-			defaultSecretFileName: "default_secret_file",
-			secretPathEnvKey:      "SECRET_FILE",
-			setupFile: func(tempDir string) error {
-				secretFilepath := filepath.Join(tempDir, "default_secret_file")
-				return os.WriteFile(secretFilepath, nil, os.ModePerm)
-			},
-			stringPtr: ptrTo(""),
-		},
-		"default_secret_file": {
-			defaultSecretFileName: "default_secret_file",
-			secretPathEnvKey:      "SECRET_FILE",
-			setupFile: func(tempDir string) error {
-				secretFilepath := filepath.Join(tempDir, "default_secret_file")
-				return os.WriteFile(secretFilepath, []byte("A"), os.ModePerm)
-			},
-			stringPtr: ptrTo("A"),
-		},
-		"env_specified_secret_file": {
-			source: func(tempDir string) Source {
-				secretFilepath := filepath.Join(tempDir, "secret_file")
-				environ := []string{"SECRET_FILE=" + secretFilepath}
-				return Source{env: *env.New(environ, nil)}
-			},
-			defaultSecretFileName: "default_secret_file",
-			secretPathEnvKey:      "SECRET_FILE",
-			setupFile: func(tempDir string) error {
-				secretFilepath := filepath.Join(tempDir, "secret_file")
-				return os.WriteFile(secretFilepath, []byte("B"), os.ModePerm)
-			},
-			stringPtr: ptrTo("B"),
-		},
-	}
-
-	for name, testCase := range testCases {
-		testCase := testCase
-		t.Run(name, func(t *testing.T) {
-			t.Parallel()
-			tempDir := t.TempDir()
-
-			var source Source
-			if testCase.source != nil {
-				source = testCase.source(tempDir)
-			}
-
-			defaultSecretPath := filepath.Join(tempDir, testCase.defaultSecretFileName)
-			if testCase.setupFile != nil {
-				err := testCase.setupFile(tempDir)
-				require.NoError(t, err)
-			}
-
-			stringPtr, err := source.readSecretFileAsStringPtr(
-				testCase.secretPathEnvKey, defaultSecretPath)
-
-			assert.Equal(t, testCase.stringPtr, stringPtr)
-			assert.ErrorIs(t, err, testCase.errWrapped)
-			if testCase.errWrapped != nil {
-				assert.EqualError(t, err, testCase.errMessage)
-			}
-		})
-	}
-}
--- a/internal/configuration/sources/secrets/httpproxy.go
+++ b/internal/configuration/sources/secrets/httpproxy.go
@@ -6,21 +6,21 @@ import (
 	"github.com/qdm12/gluetun/internal/configuration/settings"
 )

-func (s *Source) readHTTPProxy() (settings settings.HTTPProxy, err error) {
-	settings.User, err = s.readSecretFileAsStringPtr(
+func readHTTPProxy() (settings settings.HTTPProxy, err error) {
+	settings.User, err = readSecretFileAsStringPtr(
 		"HTTPPROXY_USER_SECRETFILE",
 		"/run/secrets/httpproxy_user",
 	)
 	if err != nil {
-		return settings, fmt.Errorf("reading HTTP proxy user secret file: %w", err)
+		return settings, fmt.Errorf("cannot read HTTP proxy user secret file: %w", err)
 	}

-	settings.Password, err = s.readSecretFileAsStringPtr(
+	settings.Password, err = readSecretFileAsStringPtr(
 		"HTTPPROXY_PASSWORD_SECRETFILE",
 		"/run/secrets/httpproxy_password",
 	)
 	if err != nil {
-		return settings, fmt.Errorf("reading HTTP proxy password secret file: %w", err)
+		return settings, fmt.Errorf("cannot read OpenVPN password secret file: %w", err)
 	}

 	return settings, nil
--- a/Show More
+++ b/Show More