Fix lint error

- If a default IPv6 route is found, query the ip:port defined by `IPV6_CHECK_ADDRESS` to check for internet access

.devcontainer/Dockerfile

@@ -1,2 +1,2 @@
-FROM qmcgaw/godevcontainer:v0.20-alpine
+FROM ghcr.io/qdm12/godevcontainer:v0.21-alpine
 RUN apk add wireguard-tools htop openssl

.devcontainer/README.md

@@ -19,16 +19,16 @@ It works on Linux, Windows (WSL2) and OSX.
     mkdir -p ~/.ssh
     ```
 
-1. **For Docker on OSX**: ensure the project directory and your home directory `~` are accessible by Docker.
+1. **For OSX hosts**: ensure the project directory and your home directory `~` are accessible by Docker.
 1. Open the command palette in Visual Studio Code (CTRL+SHIFT+P).
-1. Select `Dev Containers: Open Folder in Container...` and choose the project directory.
+1. Select `Dev-Containers: Open Folder in Container...` and choose the project directory.
 
 ## Customization
 
 For any customization to take effect, you should "rebuild and reopen":
 
 1. Open the command palette in Visual Studio Code (CTRL+SHIFT+P)
-2. Select `Dev Containers: Rebuild Container`
+2. Select `Dev-Containers: Rebuild Container`
 
 Changes you can make are notably:
 

.devcontainer/devcontainer.json

@@ -82,6 +82,9 @@
                 "gopls": {
                     "usePlaceholders": false,
                     "staticcheck": true,
+                    "ui.diagnostic.analyses": {
+                        "ST1000": false
+                    },
                     "formatting.gofumpt": true,
                 },
                 "go.lintTool": "golangci-lint",

.github/ISSUE_TEMPLATE/provider.md

@@ -6,12 +6,35 @@ labels: ":bulb: New provider"
 
 ---
 
-One of the following is required:
+Important notes:
 
-- Publicly accessible URL to a zip file containing the Openvpn configuration files
+- There is no need to support both OpenVPN and Wireguard for a provider, but it's better to support both if possible
-- Publicly accessible URL to a structured (JSON etc.) list of servers **and attach** an example Openvpn configuration file for both TCP and UDP
+- We do **not** implement authentication to access servers information behind a login. This is way too time consuming unfortunately
+- If it's not possible to support a provider natively, you can still use the [the custom provider](https://github.com/qdm12/gluetun-wiki/blob/main/setup/providers/custom.md)
+
+## For Wireguard
+
+Wireguard can be natively supported ONLY if:
+
+- the `PrivateKey` field value is the same across all servers for one user account
+- the `Address` field value is:
+  - can be found in a structured (JSON etc.) list of servers publicly available; OR
+  - the same across all servers for one user account
+- the `PublicKey` field value is:
+  - can be found in a structured (JSON etc.) list of servers publicly available; OR
+  - the same across all servers for one user account
+- the `Endpoint` field value:
+  - can be found in a structured (JSON etc.) list of servers publicly available
+  - can be determined using a pattern, for example using country codes in hostnames
+
+If any of these conditions are not met, Wireguard cannot be natively supported or there is no advantage compared to using a custom Wireguard configuration file.
+
+If **all** of these conditions are met, please provide an answer for each of them.
+
+## For OpenVPN
+
+OpenVPN can be natively supported ONLY if one of the following can be provided, by preference in this order:
+
+- Publicly accessible URL to a structured (JSON etc.) list of servers **and attach** an example Openvpn configuration file for both TCP and UDP; OR
+- Publicly accessible URL to a zip file containing the Openvpn configuration files; OR
 - Publicly accessible URL to the list of servers **and attach** an example Openvpn configuration file for both TCP and UDP
-
-If the list of servers requires to login **or** is hidden behind an interactive configurator,
-you can only use a custom Openvpn configuration file.
-[The Wiki's OpenVPN configuration file page](https://github.com/qdm12/gluetun-wiki/blob/main/setup/openvpn-configuration-file.md) describes how to do so.

.github/pull_request_template.md

@@ -0,0 +1,12 @@
+# Description
+
+<!-- Please describe the reason for the changes being proposed. -->
+
+# Issue
+
+<!-- Please link to the issue(s) this change relates to. -->
+
+# Assertions
+
+* [ ] I am aware that we do not accept manual changes to the servers.json file <!-- If this is your goal, please consult https://github.com/qdm12/gluetun-wiki/blob/main/setup/servers.md#update-using-the-command-line -->
+* [ ] I am aware that any changes to settings should be reflected in the [wiki](https://github.com/qdm12/gluetun-wiki/)

.github/workflows/ci.yml

@@ -37,7 +37,7 @@ jobs:
     env:
       DOCKER_BUILDKIT: "1"
     steps:
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@v5
 
       - uses: reviewdog/action-misspell@v1
         with:
@@ -66,6 +66,33 @@ jobs:
       - name: Build final image
         run: docker build -t final-image .
 
+  verify-private:
+    if: |
+      github.repository == 'qdm12/gluetun' &&
+      (
+        github.event_name == 'push' ||
+        github.event_name == 'release' ||
+        (github.event_name == 'pull_request' && github.event.pull_request.head.repo.full_name == github.repository && github.actor != 'dependabot[bot]')
+      )
+    needs: [verify]
+    runs-on: ubuntu-latest
+    environment: secrets
+    steps:
+      - uses: actions/checkout@v5
+
+      - run: docker build -t qmcgaw/gluetun .
+
+      - name: Setup Go for CI utility
+        uses: actions/setup-go@v6
+        with:
+          go-version-file: ci/go.mod
+
+      - name: Build utility
+        run: go build -C ./ci -o runner ./cmd/main.go
+
+      - name: Run Gluetun container with Mullvad configuration
+        run: echo -e "${{ secrets.MULLVAD_WIREGUARD_PRIVATE_KEY }}\n${{ secrets.MULLVAD_WIREGUARD_ADDRESS }}" | ./ci/runner mullvad
+
   codeql:
     runs-on: ubuntu-latest
     permissions:
@@ -73,15 +100,15 @@ jobs:
       contents: read
       security-events: write
     steps:
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@v5
-      - uses: actions/setup-go@v5
+      - uses: actions/setup-go@v6
         with:
-          go-version: "^1.23"
+          go-version-file: go.mod
-      - uses: github/codeql-action/init@v3
+      - uses: github/codeql-action/init@v4
         with:
           languages: go
-      - uses: github/codeql-action/autobuild@v3
+      - uses: github/codeql-action/autobuild@v4
-      - uses: github/codeql-action/analyze@v3
+      - uses: github/codeql-action/analyze@v4
 
   publish:
     if: |
@@ -98,7 +125,7 @@ jobs:
       packages: write
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@v5
 
       # extract metadata (tags, labels) for Docker
       # https://github.com/docker/metadata-action

.github/workflows/closed-issue.yml

@@ -9,7 +9,7 @@ jobs:
       issues: write
     runs-on: ubuntu-latest
     steps:
-      - uses: peter-evans/create-or-update-comment@v4
+      - uses: peter-evans/create-or-update-comment@v5
         with:
           token: ${{ github.token }}
           issue-number: ${{ github.event.issue.number }}

.github/workflows/configs/mlc-config.json

@@ -8,6 +8,7 @@
   "retryOn429": false,
   "fallbackRetryDelay": "30s",
   "aliveStatusCodes": [
-    200
+    200,
+    429
   ]
 }

.github/workflows/labels.yml

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

.github/workflows/markdown.yml

@@ -18,12 +18,12 @@ jobs:
       actions: read
       contents: read
     steps:
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@v5
 
-      - uses: DavidAnson/markdownlint-cli2-action@v18
+      - uses: DavidAnson/markdownlint-cli2-action@v20
         with:
           globs: "**.md"
-          config: .markdownlint.json
+          config: .markdownlint-cli2.jsonc
 
       - uses: reviewdog/action-misspell@v1
         with:

.github/workflows/opened-issue.yml

@@ -9,7 +9,7 @@ jobs:
       issues: write
     runs-on: ubuntu-latest
     steps:
-      - uses: peter-evans/create-or-update-comment@v4
+      - uses: peter-evans/create-or-update-comment@v5
         with:
           token: ${{ github.token }}
           issue-number: ${{ github.event.issue.number }}

.golangci.yml

@@ -1,27 +1,70 @@
-linters-settings:
+version: "2"
-  misspell:
-    locale: US
 
-issues:
+formatters:
-  exclude-rules:
+  enable:
-    - path: _test\.go
+    - gci
-      linters:
+    - gofumpt
-        - dupl
+    - goimports
-        - err113
+  exclusions:
-        - containedctx
+    generated: lax
-        - maintidx
+    paths:
-    - path: "internal\\/server\\/.+\\.go"
+      - third_party$
-      linters:
+      - builtin$
-        - dupl
+      - examples$
-    - 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:
+  settings:
+    misspell:
+      locale: US
+    goconst:
+      ignore-string-values:
+        # commonly used settings strings
+        - "^disabled$"
+        # Firewall and routing strings
+        - "^(ACCEPT|DROP)$"
+        - "^--delete$"
+        - "^all$"
+        - "^(tcp|udp)$"
+        # Server route strings
+        - "^/status$"
+
+  exclusions:
+    generated: lax
+    presets:
+      - comments
+      - common-false-positives
+      - legacy
+      - std-error-handling
+    rules:
+      - linters:
+          - containedctx
+          - dupl
+          - err113
+          - maintidx
+        path: _test\.go
+      - linters:
+          - dupl
+        path: internal\/server\/.+\.go
+      - linters:
+          - ireturn
+        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:
+          - revive
+        path: internal\/provider\/(common|utils)\/.+\.go
+        text: "var-naming: avoid (bad|meaningless) package names"
+      - linters:
+          - err113
+          - mnd
+        path: ci\/.+\.go
+
+    paths:
+      - third_party$
+      - builtin$
+      - examples$
   enable:
     # - cyclop
     # - errorlint
@@ -42,7 +85,6 @@ linters:
     - exhaustive
     - fatcontext
     - forcetypeassert
-    - gci
     - gocheckcompilerdirectives
     - gochecknoglobals
     - gochecknoinits
@@ -51,9 +93,7 @@ linters:
     - gocritic
     - gocyclo
     - godot
-    - gofumpt
     - goheader
-    - goimports
     - gomoddirectives
     - goprintffuncname
     - gosec
@@ -86,7 +126,6 @@ linters:
     - rowserrcheck
     - sqlclosecheck
     - tagalign
-    - tenv
     - thelper
     - tparallel
     - unconvert

.markdownlint-cli2.jsonc

@@ -0,0 +1,9 @@
+{
+  "config": {
+    "default": true,
+    "MD013": false,
+  },
+  "ignores": [
+    ".github/pull_request_template.md"
+  ]
+}

.markdownlint.json

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

.vscode/launch.json

@@ -1,35 +0,0 @@
-{
-    "version": "0.2.0",
-    "configurations": [
-        {
-            "name": "Update a VPN provider servers data",
-            "type": "go",
-            "request": "launch",
-            "cwd": "${workspaceFolder}",
-            "program": "cmd/gluetun/main.go",
-            "args": [
-                "update",
-                "${input:updateMode}",
-                "-providers",
-                "${input:provider}"
-            ],
-        }
-    ],
-    "inputs": [
-        {
-            "id": "provider",
-            "type": "promptString",
-            "description": "Please enter a provider (or comma separated list of providers)",
-        },
-        {
-            "id": "updateMode",
-            "type": "pickString",
-            "description": "Update mode to use",
-            "options": [
-                "-maintainer",
-                "-enduser"
-            ],
-            "default": "-maintainer"
-        },
-    ]
-}

.vscode/tasks.json

@@ -0,0 +1,51 @@
+{
+    "version": "2.0.0",
+    "tasks": [
+        {
+            "label": "Update a VPN provider servers data",
+            "type": "shell",
+            "command": "go",
+            "args": [
+                "run",
+                "./cmd/gluetun/main.go",
+                "update",
+                "${input:updateMode}",
+                "-providers",
+                "${input:provider}"
+            ],
+        },
+        {
+            "label": "Add a Gluetun Github Git remote",
+            "type": "shell",
+            "command": "git",
+            "args": [
+                "remote",
+                "add",
+                "${input:githubRemoteUsername}",
+                "git@github.com:${input:githubRemoteUsername}/gluetun.git"
+            ],
+        }
+    ],
+    "inputs": [
+        {
+            "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"
+        },
+        {
+            "id": "githubRemoteUsername",
+            "type": "promptString",
+            "description": "Please enter a Github username",
+        },
+    ]
+}

Dockerfile

@@ -1,14 +1,14 @@
-ARG ALPINE_VERSION=3.20
+ARG ALPINE_VERSION=3.22
-ARG GO_ALPINE_VERSION=3.20
+ARG GO_ALPINE_VERSION=3.22
-ARG GO_VERSION=1.23
+ARG GO_VERSION=1.25
-ARG XCPUTRANSLATE_VERSION=v0.6.0
+ARG XCPUTRANSLATE_VERSION=v0.9.0
-ARG GOLANGCI_LINT_VERSION=v1.61.0
+ARG GOLANGCI_LINT_VERSION=v2.4.0
 ARG MOCKGEN_VERSION=v1.6.0
 ARG BUILDPLATFORM=linux/amd64
 
-FROM --platform=${BUILDPLATFORM} qmcgaw/xcputranslate:${XCPUTRANSLATE_VERSION} AS xcputranslate
+FROM --platform=${BUILDPLATFORM} ghcr.io/qdm12/xcputranslate:${XCPUTRANSLATE_VERSION} AS xcputranslate
-FROM --platform=${BUILDPLATFORM} qmcgaw/binpot:golangci-lint-${GOLANGCI_LINT_VERSION} AS golangci-lint
+FROM --platform=${BUILDPLATFORM} ghcr.io/qdm12/binpot:golangci-lint-${GOLANGCI_LINT_VERSION} AS golangci-lint
-FROM --platform=${BUILDPLATFORM} qmcgaw/binpot:mockgen-${MOCKGEN_VERSION} AS mockgen
+FROM --platform=${BUILDPLATFORM} ghcr.io/qdm12/binpot:mockgen-${MOCKGEN_VERSION} AS mockgen
 
 FROM --platform=${BUILDPLATFORM} golang:${GO_VERSION}-alpine${GO_ALPINE_VERSION} AS base
 COPY --from=xcputranslate /xcputranslate /usr/local/bin/xcputranslate
@@ -32,7 +32,7 @@ ENTRYPOINT go test -race -coverpkg=./... -coverprofile=coverage.txt -covermode=a
 
 FROM --platform=${BUILDPLATFORM} base AS lint
 COPY .golangci.yml ./
-RUN golangci-lint run --timeout=10m
+RUN golangci-lint run
 
 FROM --platform=${BUILDPLATFORM} base AS mocks
 RUN git init && \
@@ -159,24 +159,27 @@ ENV VPN_SERVICE_PROVIDER=pia \
     FIREWALL_INPUT_PORTS= \
     FIREWALL_OUTBOUND_SUBNETS= \
     FIREWALL_DEBUG=off \
+    # IPv6
+    IPV6_CHECK_ADDRESS=[2606:4700::6810:84e5]:443 \
     # Logging
     LOG_LEVEL=info \
     # Health
     HEALTH_SERVER_ADDRESS=127.0.0.1:9999 \
     HEALTH_TARGET_ADDRESS=cloudflare.com:443 \
-    HEALTH_SUCCESS_WAIT_DURATION=5s \
+    HEALTH_ICMP_TARGET_IP=1.1.1.1 \
-    HEALTH_VPN_DURATION_INITIAL=6s \
+    HEALTH_RESTART_VPN=on \
-    HEALTH_VPN_DURATION_ADDITION=5s \
+    # DNS
-    # DNS over TLS
+    DNS_SERVER=on \
-    DOT=on \
+    DNS_UPSTREAM_RESOLVER_TYPE=DoT \
-    DOT_PROVIDERS=cloudflare \
+    DNS_UPSTREAM_RESOLVERS=cloudflare \
-    DOT_PRIVATE_ADDRESS=127.0.0.1/8,10.0.0.0/8,172.16.0.0/12,192.168.0.0/16,169.254.0.0/16,::1/128,fc00::/7,fe80::/10,::ffff:7f00:1/104,::ffff:a00:0/104,::ffff:a9fe:0/112,::ffff:ac10:0/108,::ffff:c0a8:0/112 \
+    DNS_BLOCK_IPS= \
-    DOT_CACHING=on \
+    DNS_BLOCK_IP_PREFIXES=127.0.0.1/8,10.0.0.0/8,172.16.0.0/12,192.168.0.0/16,169.254.0.0/16,::1/128,fc00::/7,fe80::/10,::ffff:7f00:1/104,::ffff:a00:0/104,::ffff:a9fe:0/112,::ffff:ac10:0/108,::ffff:c0a8:0/112 \
-    DOT_IPV6=off \
+    DNS_CACHING=on \
+    DNS_UPSTREAM_IPV6=off \
     BLOCK_MALICIOUS=on \
     BLOCK_SURVEILLANCE=off \
     BLOCK_ADS=off \
-    UNBLOCK= \
+    DNS_UNBLOCK_HOSTNAMES= \
     DNS_UPDATE_PERIOD=24h \
     DNS_ADDRESS=127.0.0.1 \
     DNS_KEEP_NAMESERVER=off \

README.md

@@ -1,6 +1,6 @@
 # Gluetun VPN client
 
-Lightweight swiss-knife-like VPN client to multiple VPN service providers
+Lightweight swiss-army-knife-like VPN client to multiple VPN service providers
 
 ![Title image](https://raw.githubusercontent.com/qdm12/gluetun/master/title.svg)
 
@@ -26,7 +26,6 @@ Lightweight swiss-knife-like VPN client to multiple VPN service providers
 [![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)
@@ -56,7 +55,7 @@ Lightweight swiss-knife-like VPN client to multiple VPN service providers
 
 ## Features
 
-- Based on Alpine 3.20 for a small Docker image of 35.6MB
+- Based on Alpine 3.22 for a small Docker image of 41.1MB
 - Supports: **AirVPN**, **Cyberghost**, **ExpressVPN**, **FastestVPN**, **Giganews**, **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
@@ -88,7 +87,7 @@ Go to the [Wiki](https://github.com/qdm12/gluetun-wiki)!
 Here's a docker-compose.yml for the laziest:
 
 ```yml
-version: "3"
+---
 services:
   gluetun:
     image: qmcgaw/gluetun

ci/cmd/main.go

@@ -0,0 +1,33 @@
+package main
+
+import (
+	"context"
+	"fmt"
+	"os"
+	"os/signal"
+
+	"github.com/qdm12/gluetun/ci/internal"
+)
+
+func main() {
+	if len(os.Args) < 2 {
+		fmt.Println("Usage: " + os.Args[0] + " <command>")
+		os.Exit(1)
+	}
+
+	ctx, stop := signal.NotifyContext(context.Background(), os.Interrupt)
+
+	var err error
+	switch os.Args[1] {
+	case "mullvad":
+		err = internal.MullvadTest(ctx)
+	default:
+		err = fmt.Errorf("unknown command: %s", os.Args[1])
+	}
+	stop()
+	if err != nil {
+		fmt.Println("❌", err)
+		os.Exit(1)
+	}
+	fmt.Println("✅ Test completed successfully.")
+}

ci/go.mod

@@ -0,0 +1,36 @@
+module github.com/qdm12/gluetun/ci
+
+go 1.25.0
+
+require (
+	github.com/docker/docker v28.5.1+incompatible
+	github.com/opencontainers/image-spec v1.1.1
+)
+
+require (
+	github.com/Microsoft/go-winio v0.6.2 // indirect
+	github.com/containerd/errdefs v1.0.0 // indirect
+	github.com/containerd/errdefs/pkg v0.3.0 // indirect
+	github.com/containerd/log v0.1.0 // indirect
+	github.com/distribution/reference v0.6.0 // indirect
+	github.com/docker/go-connections v0.6.0 // indirect
+	github.com/docker/go-units v0.5.0 // indirect
+	github.com/felixge/httpsnoop v1.0.4 // indirect
+	github.com/go-logr/logr v1.4.3 // indirect
+	github.com/go-logr/stdr v1.2.2 // indirect
+	github.com/moby/docker-image-spec v1.3.1 // indirect
+	github.com/moby/sys/atomicwriter v0.1.0 // indirect
+	github.com/moby/term v0.5.2 // indirect
+	github.com/morikuni/aec v1.0.0 // indirect
+	github.com/opencontainers/go-digest v1.0.0 // indirect
+	github.com/pkg/errors v0.9.1 // indirect
+	go.opentelemetry.io/auto/sdk v1.1.0 // indirect
+	go.opentelemetry.io/contrib/instrumentation/net/http/otelhttp v0.63.0 // indirect
+	go.opentelemetry.io/otel v1.38.0 // indirect
+	go.opentelemetry.io/otel/exporters/otlp/otlptrace/otlptracehttp v1.38.0 // indirect
+	go.opentelemetry.io/otel/metric v1.38.0 // indirect
+	go.opentelemetry.io/otel/trace v1.38.0 // indirect
+	golang.org/x/sys v0.35.0 // indirect
+	golang.org/x/time v0.14.0 // indirect
+	gotest.tools/v3 v3.5.2 // indirect
+)

ci/go.sum

@@ -0,0 +1,97 @@
+github.com/Azure/go-ansiterm v0.0.0-20250102033503-faa5f7b0171c h1:udKWzYgxTojEKWjV8V+WSxDXJ4NFATAsZjh8iIbsQIg=
+github.com/Azure/go-ansiterm v0.0.0-20250102033503-faa5f7b0171c/go.mod h1:xomTg63KZ2rFqZQzSB4Vz2SUXa1BpHTVz9L5PTmPC4E=
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ci/internal/mullvad.go

@@ -0,0 +1,193 @@
+package internal
+
+import (
+	"bufio"
+	"context"
+	"fmt"
+	"io"
+	"os"
+	"regexp"
+	"strings"
+	"time"
+
+	"github.com/docker/docker/api/types/container"
+	"github.com/docker/docker/api/types/network"
+	"github.com/docker/docker/client"
+	v1 "github.com/opencontainers/image-spec/specs-go/v1"
+)
+
+func MullvadTest(ctx context.Context) error {
+	secrets, err := readSecrets(ctx)
+	if err != nil {
+		return fmt.Errorf("reading secrets: %w", err)
+	}
+
+	const timeout = 15 * time.Second
+	ctx, cancel := context.WithTimeout(ctx, timeout)
+	defer cancel()
+
+	client, err := client.NewClientWithOpts(client.FromEnv, client.WithAPIVersionNegotiation())
+	if err != nil {
+		return fmt.Errorf("creating Docker client: %w", err)
+	}
+	defer client.Close()
+
+	config := &container.Config{
+		Image:       "qmcgaw/gluetun",
+		StopTimeout: ptrTo(3),
+		Env: []string{
+			"VPN_SERVICE_PROVIDER=mullvad",
+			"VPN_TYPE=wireguard",
+			"LOG_LEVEL=debug",
+			"SERVER_COUNTRIES=USA",
+			"WIREGUARD_PRIVATE_KEY=" + secrets.mullvadWireguardPrivateKey,
+			"WIREGUARD_ADDRESSES=" + secrets.mullvadWireguardAddress,
+		},
+	}
+	hostConfig := &container.HostConfig{
+		AutoRemove: true,
+		CapAdd:     []string{"NET_ADMIN", "NET_RAW"},
+	}
+	networkConfig := (*network.NetworkingConfig)(nil)
+	platform := (*v1.Platform)(nil)
+	const containerName = "" // auto-generated name
+
+	response, err := client.ContainerCreate(ctx, config, hostConfig, networkConfig, platform, containerName)
+	if err != nil {
+		return fmt.Errorf("creating container: %w", err)
+	}
+	for _, warning := range response.Warnings {
+		fmt.Println("Warning during container creation:", warning)
+	}
+	containerID := response.ID
+	defer stopContainer(client, containerID)
+
+	beforeStartTime := time.Now()
+
+	err = client.ContainerStart(ctx, containerID, container.StartOptions{})
+	if err != nil {
+		return fmt.Errorf("starting container: %w", err)
+	}
+
+	return waitForLogLine(ctx, client, containerID, beforeStartTime)
+}
+
+func ptrTo[T any](v T) *T { return &v }
+
+type secrets struct {
+	mullvadWireguardPrivateKey string
+	mullvadWireguardAddress    string
+}
+
+func readSecrets(ctx context.Context) (secrets, error) {
+	expectedSecrets := [...]string{
+		"Mullvad Wireguard private key",
+		"Mullvad Wireguard address",
+	}
+
+	scanner := bufio.NewScanner(os.Stdin)
+	lines := make([]string, 0, len(expectedSecrets))
+
+	for i := range expectedSecrets {
+		fmt.Println("🤫 reading", expectedSecrets[i], "from Stdin...")
+		if !scanner.Scan() {
+			break
+		}
+		lines = append(lines, strings.TrimSpace(scanner.Text()))
+		if ctx.Err() != nil {
+			return secrets{}, ctx.Err()
+		}
+	}
+
+	if err := scanner.Err(); err != nil {
+		return secrets{}, fmt.Errorf("reading secrets from stdin: %w", err)
+	}
+
+	if len(lines) < len(expectedSecrets) {
+		return secrets{}, fmt.Errorf("expected %d secrets via Stdin, but only received %d",
+			len(expectedSecrets), len(lines))
+	}
+	for i, line := range lines {
+		if line == "" {
+			return secrets{}, fmt.Errorf("secret on line %d/%d was empty", i+1, len(lines))
+		}
+	}
+
+	return secrets{
+		mullvadWireguardPrivateKey: lines[0],
+		mullvadWireguardAddress:    lines[1],
+	}, nil
+}
+
+func stopContainer(client *client.Client, containerID string) {
+	const stopTimeout = 5 * time.Second // must be higher than 3s, see above [container.Config]'s StopTimeout field
+	stopCtx, stopCancel := context.WithTimeout(context.Background(), stopTimeout)
+	defer stopCancel()
+
+	err := client.ContainerStop(stopCtx, containerID, container.StopOptions{})
+	if err != nil {
+		fmt.Println("failed to stop container:", err)
+	}
+}
+
+var successRegexp = regexp.MustCompile(`^.+Public IP address is .+$`)
+
+func waitForLogLine(ctx context.Context, client *client.Client, containerID string,
+	beforeStartTime time.Time,
+) error {
+	logOptions := container.LogsOptions{
+		ShowStdout: true,
+		Follow:     true,
+		Since:      beforeStartTime.Format(time.RFC3339Nano),
+	}
+
+	reader, err := client.ContainerLogs(ctx, containerID, logOptions)
+	if err != nil {
+		return fmt.Errorf("error getting container logs: %w", err)
+	}
+	defer reader.Close()
+
+	var linesSeen []string
+	scanner := bufio.NewScanner(reader)
+	for ctx.Err() == nil {
+		if scanner.Scan() {
+			line := scanner.Text()
+			if len(line) > 8 { // remove Docker log prefix
+				line = line[8:]
+			}
+			linesSeen = append(linesSeen, line)
+			if successRegexp.MatchString(line) {
+				fmt.Println("✅ Success line logged")
+				return nil
+			}
+			continue
+		}
+		err := scanner.Err()
+		if err != nil && err != io.EOF {
+			logSeenLines(linesSeen)
+			return fmt.Errorf("reading log stream: %w", err)
+		}
+
+		// The scanner is either done or cannot read because of EOF
+		fmt.Println("The log scanner stopped")
+		logSeenLines(linesSeen)
+
+		// Check if the container is still running
+		inspect, err := client.ContainerInspect(ctx, containerID)
+		if err != nil {
+			return fmt.Errorf("inspecting container: %w", err)
+		}
+		if !inspect.State.Running {
+			return fmt.Errorf("container stopped unexpectedly while waiting for log line. Exit code: %d", inspect.State.ExitCode)
+		}
+	}
+
+	return ctx.Err()
+}
+
+func logSeenLines(lines []string) {
+	fmt.Println("Logs seen so far:")
+	for _, line := range lines {
+		fmt.Println("  " + line)
+	}
+}

cmd/gluetun/main.go

@@ -6,6 +6,7 @@ import (
 	"fmt"
 	"io/fs"
 	"net/http"
+	"net/netip"
 	"os"
 	"os/exec"
 	"os/signal"
@@ -242,10 +243,13 @@ func _main(ctx context.Context, buildInfo models.BuildInformation,
 		return err
 	}
 
-	ipv6Supported, err := netLinker.IsIPv6Supported()
+	ipv6SupportLevel, err := netLinker.FindIPv6SupportLevel(ctx,
+		allSettings.IPv6.CheckAddress, firewallConf)
 	if err != nil {
 		return fmt.Errorf("checking for IPv6 support: %w", err)
 	}
+	ipv6Supported := ipv6SupportLevel == netlink.IPv6Supported ||
+		ipv6SupportLevel == netlink.IPv6Internet
 
 	err = allSettings.Validate(storage, ipv6Supported, logger)
 	if err != nil {
@@ -414,6 +418,13 @@ func _main(ctx context.Context, buildInfo models.BuildInformation,
 		return fmt.Errorf("starting public ip loop: %w", err)
 	}
 
+	healthLogger := logger.New(log.SetComponent("healthcheck"))
+	healthcheckServer := healthcheck.NewServer(allSettings.Health, healthLogger)
+	healthServerHandler, healthServerCtx, healthServerDone := goshutdown.NewGoRoutineHandler(
+		"HTTP health server", goroutine.OptionTimeout(defaultShutdownTimeout))
+	go healthcheckServer.Run(healthServerCtx, healthServerDone)
+	healthChecker := healthcheck.NewChecker(healthLogger)
+
 	updaterLogger := logger.New(log.SetComponent("updater"))
 
 	unzipper := unzip.New(httpClient)
@@ -423,9 +434,9 @@ func _main(ctx context.Context, buildInfo models.BuildInformation,
 		httpClient, unzipper, parallelResolver, publicIPLooper.Fetcher(), openvpnFileExtractor)
 
 	vpnLogger := logger.New(log.SetComponent("vpn"))
-	vpnLooper := vpn.NewLoop(allSettings.VPN, ipv6Supported, allSettings.Firewall.VPNInputPorts,
+	vpnLooper := vpn.NewLoop(allSettings.VPN, ipv6SupportLevel, allSettings.Firewall.VPNInputPorts,
-		providers, storage, ovpnConf, netLinker, firewallConf, routingConf, portForwardLooper,
+		providers, storage, allSettings.Health, healthChecker, healthcheckServer, ovpnConf, netLinker, firewallConf,
-		cmder, publicIPLooper, dnsLooper, vpnLogger, httpClient,
+		routingConf, portForwardLooper, cmder, publicIPLooper, dnsLooper, vpnLogger, httpClient,
 		buildInfo, *allSettings.Version.Enabled)
 	vpnHandler, vpnCtx, vpnDone := goshutdown.NewGoRoutineHandler(
 		"vpn", goroutine.OptionTimeout(time.Second))
@@ -467,7 +478,7 @@ func _main(ctx context.Context, buildInfo models.BuildInformation,
 		logger.New(log.SetComponent("http server")),
 		allSettings.ControlServer.AuthFilePath,
 		buildInfo, vpnLooper, portForwardLooper, dnsLooper, updaterLooper, publicIPLooper,
-		storage, ipv6Supported)
+		storage, ipv6SupportLevel.IsSupported())
 	if err != nil {
 		return fmt.Errorf("setting up control server: %w", err)
 	}
@@ -476,12 +487,6 @@ func _main(ctx context.Context, buildInfo models.BuildInformation,
 	<-httpServerReady
 	controlGroupHandler.Add(httpServerHandler)
 
-	healthLogger := logger.New(log.SetComponent("healthcheck"))
-	healthcheckServer := healthcheck.NewServer(allSettings.Health, healthLogger, vpnLooper)
-	healthServerHandler, healthServerCtx, healthServerDone := goshutdown.NewGoRoutineHandler(
-		"HTTP health server", goroutine.OptionTimeout(defaultShutdownTimeout))
-	go healthcheckServer.Run(healthServerCtx, healthServerDone)
-
 	orderHandler := goshutdown.NewOrderHandler("gluetun",
 		order.OptionTimeout(totalShutdownTimeout),
 		order.OptionOnSuccess(defaultShutdownOnSuccess),
@@ -549,7 +554,9 @@ type netLinker interface {
 	Ruler
 	Linker
 	IsWireguardSupported() (ok bool, err error)
-	IsIPv6Supported() (ok bool, err error)
+	FindIPv6SupportLevel(ctx context.Context,
+		checkAddress netip.AddrPort, firewall netlink.Firewall,
+	) (level netlink.IPv6SupportLevel, err error)
 	PatchLoggerLevel(level log.Level)
 }
 

go.mod

@@ -1,29 +1,29 @@
 module github.com/qdm12/gluetun
 
-go 1.23
+go 1.25.0
 
 require (
-	github.com/breml/rootcerts v0.2.19
+	github.com/breml/rootcerts v0.3.3
 	github.com/fatih/color v1.18.0
 	github.com/golang/mock v1.6.0
-	github.com/klauspost/compress v1.17.11
+	github.com/klauspost/compress v1.18.1
 	github.com/klauspost/pgzip v1.2.6
-	github.com/pelletier/go-toml/v2 v2.2.3
+	github.com/pelletier/go-toml/v2 v2.2.4
-	github.com/qdm12/dns/v2 v2.0.0-rc8
+	github.com/qdm12/dns/v2 v2.0.0-rc9
 	github.com/qdm12/gosettings v0.4.4
 	github.com/qdm12/goshutdown v0.3.0
 	github.com/qdm12/gosplash v0.2.0
 	github.com/qdm12/gotree v0.3.0
 	github.com/qdm12/log v0.1.0
 	github.com/qdm12/ss-server v0.6.0
-	github.com/stretchr/testify v1.10.0
+	github.com/stretchr/testify v1.11.1
-	github.com/ulikunitz/xz v0.5.11
+	github.com/ulikunitz/xz v0.5.15
-	github.com/vishvananda/netlink v1.2.1
+	github.com/vishvananda/netlink v1.3.1
 	github.com/youmark/pkcs8 v0.0.0-20201027041543-1326539a0a0a
 	golang.org/x/exp v0.0.0-20241009180824-f66d83c29e7c
-	golang.org/x/net v0.31.0
+	golang.org/x/net v0.46.0
-	golang.org/x/sys v0.27.0
+	golang.org/x/sys v0.37.0
-	golang.org/x/text v0.20.0
+	golang.org/x/text v0.30.0
 	golang.zx2c4.com/wireguard v0.0.0-20231211153847-12269c276173
 	golang.zx2c4.com/wireguard/wgctrl v0.0.0-20230429144221-925a1e7659e6
 	gopkg.in/ini.v1 v1.67.0
@@ -47,13 +47,13 @@ require (
 	github.com/prometheus/client_model v0.6.1 // indirect
 	github.com/prometheus/common v0.60.1 // indirect
 	github.com/prometheus/procfs v0.15.1 // indirect
-	github.com/qdm12/goservices v0.1.0 // indirect
+	github.com/qdm12/goservices v0.1.1-0.20251104135713-6bee97bd4978 // indirect
 	github.com/riobard/go-bloom v0.0.0-20200614022211-cdc8013cb5b3 // indirect
-	github.com/vishvananda/netns v0.0.4 // indirect
+	github.com/vishvananda/netns v0.0.5 // indirect
-	golang.org/x/crypto v0.29.0 // indirect
+	golang.org/x/crypto v0.43.0 // indirect
-	golang.org/x/mod v0.21.0 // indirect
+	golang.org/x/mod v0.28.0 // indirect
-	golang.org/x/sync v0.9.0 // indirect
+	golang.org/x/sync v0.17.0 // indirect
-	golang.org/x/tools v0.26.0 // indirect
+	golang.org/x/tools v0.37.0 // indirect
 	golang.zx2c4.com/wintun v0.0.0-20230126152724-0fa3db229ce2 // indirect
 	google.golang.org/protobuf v1.35.1 // indirect
 	gopkg.in/yaml.v3 v3.0.1 // indirect

go.sum

@@ -1,7 +1,7 @@
 github.com/beorn7/perks v1.0.1 h1:VlbKKnNfV8bJzeqoa4cOKqO6bYr3WgKZxO8Z16+hsOM=
 github.com/beorn7/perks v1.0.1/go.mod h1:G2ZrVWU2WbWT9wwq4/hrbKbnv/1ERSJQ0ibhJ6rlkpw=
-github.com/breml/rootcerts v0.2.19 h1:3D/qwAC1xoh82GmZ21mYzQ1NaLOICUVntIo+MRZYr4U=
+github.com/breml/rootcerts v0.3.3 h1://GnaRtQ/9BY2+GtMk2wtWxVdCRysiaPr5/xBwl7NKw=
-github.com/breml/rootcerts v0.2.19/go.mod h1:S/PKh+4d1HUn4HQovEB8hPJZO6pUZYrIhmXBhsegfXw=
+github.com/breml/rootcerts v0.3.3/go.mod h1:S/PKh+4d1HUn4HQovEB8hPJZO6pUZYrIhmXBhsegfXw=
 github.com/cespare/xxhash/v2 v2.3.0 h1:UL815xU9SqsFlibzuggzjXhog7bL6oX9BbNZnL2UFvs=
 github.com/cespare/xxhash/v2 v2.3.0/go.mod h1:VGX0DQ3Q6kWi7AoAeZDth3/j3BFtOZR5XLFGgcrjCOs=
 github.com/davecgh/go-spew v1.1.1 h1:vj9j/u1bqnvCEfJOwUhtlOARqs3+rkHYY13jYWTU97c=
@@ -16,8 +16,8 @@ github.com/google/go-cmp v0.6.0 h1:ofyhxvXcZhMsU5ulbFiLKl/XBFqE1GSq7atu8tAmTRI=
 github.com/google/go-cmp v0.6.0/go.mod h1:17dUlkBOakJ0+DkrSSNjCkIjxS6bF9zb3elmeNGIjoY=
 github.com/josharian/native v1.1.0 h1:uuaP0hAbW7Y4l0ZRQ6C9zfb7Mg1mbFKry/xzDAfmtLA=
 github.com/josharian/native v1.1.0/go.mod h1:7X/raswPFr05uY3HiLlYeyQntB6OO7E/d2Cu7qoaN2w=
-github.com/klauspost/compress v1.17.11 h1:In6xLpyWOi1+C7tXUUWv2ot1QvBjxevKAaI6IXrJmUc=
+github.com/klauspost/compress v1.18.1 h1:bcSGx7UbpBqMChDtsF28Lw6v/G94LPrrbMbdC3JH2co=
-github.com/klauspost/compress v1.17.11/go.mod h1:pMDklpSncoRMuLFrf1W9Ss9KT+0rH90U12bZKk7uwG0=
+github.com/klauspost/compress v1.18.1/go.mod h1:ZQFFVG+MdnR0P+l6wpXgIL4NTtwiKIdBnrBd8Nrxr+0=
 github.com/klauspost/pgzip v1.2.6 h1:8RXeL5crjEUFnR2/Sn6GJNWtSQ3Dk8pq4CL3jvdDyjU=
 github.com/klauspost/pgzip v1.2.6/go.mod h1:Ch1tH69qFZu15pkjo5kYi6mth2Zzwzt50oCQKQE9RUs=
 github.com/kr/pretty v0.3.1 h1:flRD4NNwYAUpkphVc1HcthR4KEIFJ65n8Mw5qdRn3LE=
@@ -41,8 +41,8 @@ github.com/mikioh/ipaddr v0.0.0-20190404000644-d465c8ab6721 h1:RlZweED6sbSArvlE9
 github.com/mikioh/ipaddr v0.0.0-20190404000644-d465c8ab6721/go.mod h1:Ickgr2WtCLZ2MDGd4Gr0geeCH5HybhRJbonOgQpvSxc=
 github.com/munnerz/goautoneg v0.0.0-20191010083416-a7dc8b61c822 h1:C3w9PqII01/Oq1c1nUAm88MOHcQC9l5mIlSMApZMrHA=
 github.com/munnerz/goautoneg v0.0.0-20191010083416-a7dc8b61c822/go.mod h1:+n7T8mK8HuQTcFwEeznm/DIxMOiR9yIdICNftLE1DvQ=
-github.com/pelletier/go-toml/v2 v2.2.3 h1:YmeHyLY8mFWbdkNWwpr+qIL2bEqT0o95WSdkNHvL12M=
+github.com/pelletier/go-toml/v2 v2.2.4 h1:mye9XuhQ6gvn5h28+VilKrrPoQVanw5PMw/TB0t5Ec4=
-github.com/pelletier/go-toml/v2 v2.2.3/go.mod h1:MfCQTFTvCcUyyvvwm1+G6H/jORL20Xlb6rzQu9GuUkc=
+github.com/pelletier/go-toml/v2 v2.2.4/go.mod h1:2gIqNv+qfxSVS7cM2xJQKtLSTLUE9V8t9Stt+h56mCY=
 github.com/pmezard/go-difflib v1.0.0 h1:4DBwDE0NGyQoBHbLQYPwSUPoCMWR5BEzIk/f1lZbAQM=
 github.com/pmezard/go-difflib v1.0.0/go.mod h1:iKH77koFhYxTK1pcRnkKkqfTogsbg7gZNVY4sRDYZ/4=
 github.com/prometheus/client_golang v1.20.5 h1:cxppBPuYhUnsO6yo/aoRol4L7q7UFfdm+bR9r+8l63Y=
@@ -53,10 +53,10 @@ github.com/prometheus/common v0.60.1 h1:FUas6GcOw66yB/73KC+BOZoFJmbo/1pojoILArPA
 github.com/prometheus/common v0.60.1/go.mod h1:h0LYf1R1deLSKtD4Vdg8gy4RuOvENW2J/h19V5NADQw=
 github.com/prometheus/procfs v0.15.1 h1:YagwOFzUgYfKKHX6Dr+sHT7km/hxC76UB0learggepc=
 github.com/prometheus/procfs v0.15.1/go.mod h1:fB45yRUv8NstnjriLhBQLuOUt+WW4BsoGhij/e3PBqk=
-github.com/qdm12/dns/v2 v2.0.0-rc8 h1:kbgKPkbT+79nScfuZ0ZcVhksTGo8IUqQ8TTQGnQlZ18=
+github.com/qdm12/dns/v2 v2.0.0-rc9 h1:qDzRkHr6993jknNB/ZOCnZOyIG6bsZcl2MIfdeUd0kI=
-github.com/qdm12/dns/v2 v2.0.0-rc8/go.mod h1:VaF02KWEL7xNV4oKfG4N9nEv/kR6bqyIcBReCV5NJhw=
+github.com/qdm12/dns/v2 v2.0.0-rc9/go.mod h1:98foWgXJZ+g8gJIuO+fdO+oWpFei5WShMFTeN4Im2lE=
-github.com/qdm12/goservices v0.1.0 h1:9sODefm/yuIGS7ynCkEnNlMTAYn9GzPhtcK4F69JWvc=
+github.com/qdm12/goservices v0.1.1-0.20251104135713-6bee97bd4978 h1:TRGpCU1l0lNwtogEUSs5U+RFceYxkAJUmrGabno7J5c=
-github.com/qdm12/goservices v0.1.0/go.mod h1:/JOFsAnHFiSjyoXxa5FlfX903h20K5u/3rLzCjYVMck=
+github.com/qdm12/goservices v0.1.1-0.20251104135713-6bee97bd4978/go.mod h1:D1Po4CRQLYjccnAR2JsVlN1sBMgQrcNLONbvyuzcdTg=
 github.com/qdm12/gosettings v0.4.4 h1:SM6tOZDf6k8qbjWU8KWyBF4mWIixfsKCfh9DGRLHlj4=
 github.com/qdm12/gosettings v0.4.4/go.mod h1:CPrt2YC4UsURTrslmhxocVhMCW03lIrqdH2hzIf5prg=
 github.com/qdm12/goshutdown v0.3.0 h1:pqBpJkdwlZlfTEx4QHtS8u8CXx6pG0fVo6S1N0MpSEM=
@@ -73,36 +73,36 @@ github.com/riobard/go-bloom v0.0.0-20200614022211-cdc8013cb5b3 h1:f/FNXud6gA3MNr
 github.com/riobard/go-bloom v0.0.0-20200614022211-cdc8013cb5b3/go.mod h1:HgjTstvQsPGkxUsCd2KWxErBblirPizecHcpD3ffK+s=
 github.com/rogpeppe/go-internal v1.13.1 h1:KvO1DLK/DRN07sQ1LQKScxyZJuNnedQ5/wKSR38lUII=
 github.com/rogpeppe/go-internal v1.13.1/go.mod h1:uMEvuHeurkdAXX61udpOXGD/AzZDWNMNyH2VO9fmH0o=
-github.com/stretchr/testify v1.10.0 h1:Xv5erBjTwe/5IxqUQTdXv5kgmIvbHo3QQyRwhJsOfJA=
+github.com/stretchr/testify v1.11.1 h1:7s2iGBzp5EwR7/aIZr8ao5+dra3wiQyKjjFuvgVKu7U=
-github.com/stretchr/testify v1.10.0/go.mod h1:r2ic/lqez/lEtzL7wO/rwa5dbSLXVDPFyf8C91i36aY=
+github.com/stretchr/testify v1.11.1/go.mod h1:wZwfW3scLgRK+23gO65QZefKpKQRnfz6sD981Nm4B6U=
-github.com/ulikunitz/xz v0.5.11 h1:kpFauv27b6ynzBNT/Xy+1k+fK4WswhN/6PN5WhFAGw8=
+github.com/ulikunitz/xz v0.5.15 h1:9DNdB5s+SgV3bQ2ApL10xRc35ck0DuIX/isZvIk+ubY=
-github.com/ulikunitz/xz v0.5.11/go.mod h1:nbz6k7qbPmH4IRqmfOplQw/tblSgqTqBwxkY0oWt/14=
+github.com/ulikunitz/xz v0.5.15/go.mod h1:nbz6k7qbPmH4IRqmfOplQw/tblSgqTqBwxkY0oWt/14=
-github.com/vishvananda/netlink v1.2.1 h1:pfLv/qlJUwOTPvtWREA7c3PI4u81YkqZw1DYhI2HmLA=
+github.com/vishvananda/netlink v1.3.1 h1:3AEMt62VKqz90r0tmNhog0r/PpWKmrEShJU0wJW6bV0=
-github.com/vishvananda/netlink v1.2.1/go.mod h1:i6NetklAujEcC6fK0JPjT8qSwWyO0HLn4UKG+hGqeJs=
+github.com/vishvananda/netlink v1.3.1/go.mod h1:ARtKouGSTGchR8aMwmkzC0qiNPrrWO5JS/XMVl45+b4=
-github.com/vishvananda/netns v0.0.4 h1:Oeaw1EM2JMxD51g9uhtC0D7erkIjgmj8+JZc26m1YX8=
+github.com/vishvananda/netns v0.0.5 h1:DfiHV+j8bA32MFM7bfEunvT8IAqQ/NzSJHtcmW5zdEY=
-github.com/vishvananda/netns v0.0.4/go.mod h1:SpkAiCQRtJ6TvvxPnOSyH3BMl6unz3xZlaprSwhNNJM=
+github.com/vishvananda/netns v0.0.5/go.mod h1:SpkAiCQRtJ6TvvxPnOSyH3BMl6unz3xZlaprSwhNNJM=
 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 v1.3.5/go.mod h1:mwnBkeHKe2W/ZEtQ+71ViKU8L12m81fl3OWwC1Zlc8k=
 golang.org/x/crypto v0.0.0-20190308221718-c2843e01d9a2/go.mod h1:djNgcEr1/C05ACkg1iLfiJU5Ep61QUkGW8qpdssI0+w=
 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 v0.29.0 h1:L5SG1JTTXupVV3n6sUqMTeWbjAyfPwoda2DLX8J8FrQ=
+golang.org/x/crypto v0.43.0 h1:dduJYIi3A3KOfdGOHX8AVZ/jGiyPa3IbBozJ5kNuE04=
-golang.org/x/crypto v0.29.0/go.mod h1:+F4F4N5hv6v38hfeYwTdx20oUvLLc+QfrE9Ax9HtgRg=
+golang.org/x/crypto v0.43.0/go.mod h1:BFbav4mRNlXJL4wNeejLpWxB7wMbc79PdRGhWKncxR0=
 golang.org/x/exp v0.0.0-20241009180824-f66d83c29e7c h1:7dEasQXItcW1xKJ2+gg5VOiBnqWrJc+rq0DPKyvvdbY=
 golang.org/x/exp v0.0.0-20241009180824-f66d83c29e7c/go.mod h1:NQtJDoLvd6faHhE7m4T/1IY708gDefGGjR/iUW8yQQ8=
 golang.org/x/mod v0.4.2/go.mod h1:s0Qsj1ACt9ePp/hMypM3fl4fZqREWJwdYDEqhRiZZUA=
-golang.org/x/mod v0.21.0 h1:vvrHzRwRfVKSiLrG+d4FMl/Qi4ukBCE6kZlTUkDYRT0=
+golang.org/x/mod v0.28.0 h1:gQBtGhjxykdjY9YhZpSlZIsbnaE2+PgjfLWUQTnoZ1U=
-golang.org/x/mod v0.21.0/go.mod h1:6SkKJ3Xj0I0BrPOZoBy3bdMptDDU9oJrpohJ3eWZ1fY=
+golang.org/x/mod v0.28.0/go.mod h1:yfB/L0NOf/kmEbXjzCPOx1iK1fRutOydrCMsqRhEBxI=
 golang.org/x/net v0.0.0-20190404232315-eb5bcb51f2a3/go.mod h1:t9HGtf8HONx5eT2rtn7q6eTqICYqUVnKs3thJo3Qplg=
 golang.org/x/net v0.0.0-20190620200207-3b0461eec859/go.mod h1:z5CRVTTTmAJ677TzLLGU+0bjPO0LkuOLi4/5GtJWs/s=
 golang.org/x/net v0.0.0-20210405180319-a5a99cb37ef4/go.mod h1:p54w0d4576C0XHj96bSt6lcn1PtDYWL6XObtHCRCNQM=
-golang.org/x/net v0.31.0 h1:68CPQngjLL0r2AlUKiSxtQFKvzRVbnzLwMUn5SzcLHo=
+golang.org/x/net v0.46.0 h1:giFlY12I07fugqwPuWJi68oOnpfqFnJIJzaIIm2JVV4=
-golang.org/x/net v0.31.0/go.mod h1:P4fl1q7dY2hnZFxEk4pPSkDHF+QqjitcnDjUQyMM+pM=
+golang.org/x/net v0.46.0/go.mod h1:Q9BGdFy1y4nkUwiLvT5qtyhAnEHgnQ/zd8PfU6nc210=
 golang.org/x/sync v0.0.0-20190423024810-112230192c58/go.mod h1:RxMgew5VJxzue5/jJTE5uejpjVlOe/izrB70Jof72aM=
 golang.org/x/sync v0.0.0-20210220032951-036812b2e83c/go.mod h1:RxMgew5VJxzue5/jJTE5uejpjVlOe/izrB70Jof72aM=
-golang.org/x/sync v0.9.0 h1:fEo0HyrW1GIgZdpbhCRO0PkJajUS5H9IFUztCgEo2jQ=
+golang.org/x/sync v0.17.0 h1:l60nONMj9l5drqw6jlhIELNv9I0A4OFgRsG9k2oT9Ug=
-golang.org/x/sync v0.9.0/go.mod h1:Czt+wKu1gCyEFDUtn0jG5QVvpJ6rzVqr5aXyt9drQfk=
+golang.org/x/sync v0.17.0/go.mod h1:9KTHXmSnoGruLpwFjVSX0lNNA75CykiMECbovNTZqGI=
 golang.org/x/sys v0.0.0-20190215142949-d0b11bdaac8a/go.mod h1:STP8DvDyc/dI5b8T5hshtkjS+E42TnysNCUPdjciGhY=
 golang.org/x/sys v0.0.0-20190412213103-97732733099d/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
 golang.org/x/sys v0.0.0-20201119102817-f84b799fce68/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
@@ -112,20 +112,20 @@ golang.org/x/sys v0.0.0-20220811171246-fbc7d0a398ab/go.mod h1:oPkhp1MJrh7nUepCBc
 golang.org/x/sys v0.2.0/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
 golang.org/x/sys v0.6.0/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
 golang.org/x/sys v0.10.0/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
-golang.org/x/sys v0.27.0 h1:wBqf8DvsY9Y/2P8gAfPDEYNuS30J4lPHJxXSb/nJZ+s=
+golang.org/x/sys v0.37.0 h1:fdNQudmxPjkdUTPnLn5mdQv7Zwvbvpaxqs831goi9kQ=
-golang.org/x/sys v0.27.0/go.mod h1:/VUhepiaJMQUp4+oa/7Zr1D23ma6VTLIYjOOTFZPUcA=
+golang.org/x/sys v0.37.0/go.mod h1:OgkHotnGiDImocRcuBABYBEXf8A9a87e/uXjp9XT3ks=
 golang.org/x/term v0.0.0-20201126162022-7de9c90e9dd1/go.mod h1:bj7SfCRtBDWHUb9snDiAeCFNEtKQo2Wmx5Cou7ajbmo=
 golang.org/x/text v0.3.0/go.mod h1:NqM8EUOU14njkJ3fqMW+pc6Ldnwhi/IjpwHt7yyuwOQ=
 golang.org/x/text v0.3.3/go.mod h1:5Zoc/QRtKVWzQhOtBMvqHzDpF6irO9z98xDceosuGiQ=
-golang.org/x/text v0.20.0 h1:gK/Kv2otX8gz+wn7Rmb3vT96ZwuoxnQlY+HlJVj7Qug=
+golang.org/x/text v0.30.0 h1:yznKA/E9zq54KzlzBEAWn1NXSQ8DIp/NYMy88xJjl4k=
-golang.org/x/text v0.20.0/go.mod h1:D4IsuqiFMhST5bX19pQ9ikHC2GsaKyk/oF+pn3ducp4=
+golang.org/x/text v0.30.0/go.mod h1:yDdHFIX9t+tORqspjENWgzaCVXgk0yYnYuSZ8UzzBVM=
 golang.org/x/time v0.0.0-20220210224613-90d013bbcef8 h1:vVKdlvoWBphwdxWKrFZEuM0kGgGLxUOYcY4U/2Vjg44=
 golang.org/x/time v0.0.0-20220210224613-90d013bbcef8/go.mod h1:tRJNPiyCQ0inRvYxbN9jk5I+vvW/OXSQhTDSoE431IQ=
 golang.org/x/tools v0.0.0-20180917221912-90fa682c2a6e/go.mod h1:n7NCudcB/nEzxVGmLbDWY5pfWTLqBcC2KZ6jyYvM4mQ=
 golang.org/x/tools v0.0.0-20191119224855-298f0cb1881e/go.mod h1:b+2E5dAYhXwXZwtnZ6UAqBI28+e2cm9otk0dWdXHAEo=
 golang.org/x/tools v0.1.1/go.mod h1:o0xws9oXOQQZyjljx8fwUC0k7L1pTE6eaCbjGeHmOkk=
-golang.org/x/tools v0.26.0 h1:v/60pFQmzmT9ExmjDv2gGIfi3OqfKoEP6I5+umXlbnQ=
+golang.org/x/tools v0.37.0 h1:DVSRzp7FwePZW356yEAChSdNcQo6Nsp+fex1SUW09lE=
-golang.org/x/tools v0.26.0/go.mod h1:TPVVj70c7JJ3WCazhD8OdXcZg/og+b9+tH/KxylGwH0=
+golang.org/x/tools v0.37.0/go.mod h1:MBN5QPQtLMHVdvsbtarmTNukZDdgwdwlO5qGacAzF0w=
 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 v0.0.0-20200804184101-5ec99f83aff1/go.mod h1:I/5z698sn9Ka8TeJc9MKroUUfqBBauWjQqLJ2OPfmY0=

internal/cli/noopfirewall.go

@@ -0,0 +1,14 @@
+package cli
+
+import (
+	"context"
+	"net/netip"
+)
+
+type noopFirewall struct{}
+
+func (f *noopFirewall) AcceptOutput(_ context.Context, _, _ string, _ netip.Addr,
+	_ uint16, _ bool,
+) (err error) {
+	return nil
+}

internal/cli/openvpnconfig.go

@@ -11,6 +11,7 @@ import (
 	"github.com/qdm12/gluetun/internal/configuration/settings"
 	"github.com/qdm12/gluetun/internal/constants"
 	"github.com/qdm12/gluetun/internal/models"
+	"github.com/qdm12/gluetun/internal/netlink"
 	"github.com/qdm12/gluetun/internal/openvpn/extract"
 	"github.com/qdm12/gluetun/internal/provider"
 	"github.com/qdm12/gluetun/internal/storage"
@@ -40,7 +41,9 @@ type IPFetcher interface {
 }
 
 type IPv6Checker interface {
-	IsIPv6Supported() (supported bool, err error)
+	FindIPv6SupportLevel(ctx context.Context,
+		checkAddress netip.AddrPort, firewall netlink.Firewall,
+	) (level netlink.IPv6SupportLevel, err error)
 }
 
 func (c *CLI) OpenvpnConfig(logger OpenvpnConfigLogger, reader *reader.Reader,
@@ -56,13 +59,16 @@ func (c *CLI) OpenvpnConfig(logger OpenvpnConfigLogger, reader *reader.Reader,
 	if err != nil {
 		return err
 	}
+	allSettings.SetDefaults()
 
-	ipv6Supported, err := ipv6Checker.IsIPv6Supported()
+	ipv6SupportLevel, err := ipv6Checker.FindIPv6SupportLevel(context.Background(),
+		allSettings.IPv6.CheckAddress, &noopFirewall{})
 	if err != nil {
 		return fmt.Errorf("checking for IPv6 support: %w", err)
 	}
 
-	if err = allSettings.Validate(storage, ipv6Supported, logger); err != nil {
+	err = allSettings.Validate(storage, ipv6SupportLevel.IsSupported(), logger)
+	if err != nil {
 		return fmt.Errorf("validating settings: %w", err)
 	}
 
@@ -78,13 +84,13 @@ func (c *CLI) OpenvpnConfig(logger OpenvpnConfigLogger, reader *reader.Reader,
 		unzipper, parallelResolver, ipFetcher, openvpnFileExtractor)
 	providerConf := providers.Get(allSettings.VPN.Provider.Name)
 	connection, err := providerConf.GetConnection(
-		allSettings.VPN.Provider.ServerSelection, ipv6Supported)
+		allSettings.VPN.Provider.ServerSelection, ipv6SupportLevel == netlink.IPv6Internet)
 	if err != nil {
 		return err
 	}
 
 	lines := providerConf.OpenVPNConfig(connection,
-		allSettings.VPN.OpenVPN, ipv6Supported)
+		allSettings.VPN.OpenVPN, ipv6SupportLevel.IsSupported())
 
 	fmt.Println(strings.Join(lines, "\n"))
 	return nil

internal/configuration/settings/deprecated.go

@@ -9,9 +9,11 @@ import (
 
 func readObsolete(r *reader.Reader) (warnings []string) {
 	keyToMessage := map[string]string{
-		"DOT_VERBOSITY":           "DOT_VERBOSITY is obsolete, use LOG_LEVEL instead.",
+		"DOT_VERBOSITY":                "DOT_VERBOSITY is obsolete, use LOG_LEVEL instead.",
-		"DOT_VERBOSITY_DETAILS":   "DOT_VERBOSITY_DETAILS is obsolete because it was specific to Unbound.",
+		"DOT_VERBOSITY_DETAILS":        "DOT_VERBOSITY_DETAILS is obsolete because it was specific to Unbound.",
-		"DOT_VALIDATION_LOGLEVEL": "DOT_VALIDATION_LOGLEVEL is obsolete because DNSSEC validation is not implemented.",
+		"DOT_VALIDATION_LOGLEVEL":      "DOT_VALIDATION_LOGLEVEL is obsolete because DNSSEC validation is not implemented.",
+		"HEALTH_VPN_DURATION_INITIAL":  "HEALTH_VPN_DURATION_INITIAL is obsolete",
+		"HEALTH_VPN_DURATION_ADDITION": "HEALTH_VPN_DURATION_ADDITION is obsolete",
 	}
 	sortedKeys := maps.Keys(keyToMessage)
 	slices.Sort(sortedKeys)

internal/configuration/settings/dns.go

@@ -1,9 +1,13 @@
 package settings
 
 import (
+	"errors"
 	"fmt"
 	"net/netip"
+	"time"
 
+	"github.com/qdm12/dns/v2/pkg/provider"
+	"github.com/qdm12/gluetun/internal/configuration/settings/helpers"
 	"github.com/qdm12/gosettings"
 	"github.com/qdm12/gosettings/reader"
 	"github.com/qdm12/gotree"
@@ -11,10 +15,31 @@ import (
 
 // DNS contains settings to configure DNS.
 type DNS struct {
+	// ServerEnabled is true if the server should be running
+	// and used. It defaults to true, and cannot be nil
+	// in the internal state.
+	ServerEnabled *bool
+	// UpstreamType can be dot or plain, and defaults to dot.
+	UpstreamType string `json:"upstream_type"`
+	// UpdatePeriod is the period to update DNS block lists.
+	// It can be set to 0 to disable the update.
+	// It defaults to 24h and cannot be nil in
+	// the internal state.
+	UpdatePeriod *time.Duration
+	// Providers is a list of DNS providers
+	Providers []string `json:"providers"`
+	// Caching is true if the server should cache
+	// DNS responses.
+	Caching *bool `json:"caching"`
+	// IPv6 is true if the server should connect over IPv6.
+	IPv6 *bool `json:"ipv6"`
+	// Blacklist contains settings to configure the filter
+	// block lists.
+	Blacklist DNSBlacklist
 	// 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
+	// local server. It cannot be the zero value in the internal
 	// state.
 	ServerAddress netip.Addr
 	// KeepNameserver is true if the existing DNS server
@@ -23,20 +48,40 @@ type DNS struct {
 	// outside the VPN tunnel since it would go through
 	// the local DNS server of your Docker/Kubernetes
 	// configuration, which is likely not going through the tunnel.
-	// This will also disable the DNS over TLS server and the
+	// This will also disable the DNS forwarder server and the
 	// `ServerAddress` field will be ignored.
 	// It defaults to false and cannot be nil in the
 	// internal state.
 	KeepNameserver *bool
-	// DOT contains settings to configure the DoT
-	// server.
-	DoT DoT
 }
 
+var (
+	ErrDNSUpstreamTypeNotValid = errors.New("DNS upstream type is not valid")
+	ErrDNSUpdatePeriodTooShort = errors.New("update period is too short")
+)
+
 func (d DNS) validate() (err error) {
-	err = d.DoT.validate()
+	if !helpers.IsOneOf(d.UpstreamType, "dot", "doh", "plain") {
+		return fmt.Errorf("%w: %s", ErrDNSUpstreamTypeNotValid, d.UpstreamType)
+	}
+
+	const minUpdatePeriod = 30 * time.Second
+	if *d.UpdatePeriod != 0 && *d.UpdatePeriod < minUpdatePeriod {
+		return fmt.Errorf("%w: %s must be bigger than %s",
+			ErrDNSUpdatePeriodTooShort, *d.UpdatePeriod, minUpdatePeriod)
+	}
+
+	providers := provider.NewProviders()
+	for _, providerName := range d.Providers {
+		_, err := providers.Get(providerName)
+		if err != nil {
+			return err
+		}
+	}
+
+	err = d.Blacklist.validate()
 	if err != nil {
-		return fmt.Errorf("validating DoT settings: %w", err)
+		return err
 	}
 
 	return nil
@@ -44,9 +89,15 @@ func (d DNS) validate() (err error) {
 
 func (d *DNS) Copy() (copied DNS) {
 	return DNS{
+		ServerEnabled:  gosettings.CopyPointer(d.ServerEnabled),
+		UpstreamType:   d.UpstreamType,
+		UpdatePeriod:   gosettings.CopyPointer(d.UpdatePeriod),
+		Providers:      gosettings.CopySlice(d.Providers),
+		Caching:        gosettings.CopyPointer(d.Caching),
+		IPv6:           gosettings.CopyPointer(d.IPv6),
+		Blacklist:      d.Blacklist.copy(),
 		ServerAddress:  d.ServerAddress,
 		KeepNameserver: gosettings.CopyPointer(d.KeepNameserver),
-		DoT:            d.DoT.copy(),
 	}
 }
 
@@ -54,16 +105,48 @@ func (d *DNS) Copy() (copied DNS) {
 // settings object with any field set in the other
 // settings.
 func (d *DNS) overrideWith(other DNS) {
+	d.ServerEnabled = gosettings.OverrideWithPointer(d.ServerEnabled, other.ServerEnabled)
+	d.UpstreamType = gosettings.OverrideWithComparable(d.UpstreamType, other.UpstreamType)
+	d.UpdatePeriod = gosettings.OverrideWithPointer(d.UpdatePeriod, other.UpdatePeriod)
+	d.Providers = gosettings.OverrideWithSlice(d.Providers, other.Providers)
+	d.Caching = gosettings.OverrideWithPointer(d.Caching, other.Caching)
+	d.IPv6 = gosettings.OverrideWithPointer(d.IPv6, other.IPv6)
+	d.Blacklist.overrideWith(other.Blacklist)
 	d.ServerAddress = gosettings.OverrideWithValidator(d.ServerAddress, other.ServerAddress)
 	d.KeepNameserver = gosettings.OverrideWithPointer(d.KeepNameserver, other.KeepNameserver)
-	d.DoT.overrideWith(other.DoT)
 }
 
 func (d *DNS) setDefaults() {
-	localhost := netip.AddrFrom4([4]byte{127, 0, 0, 1})
+	d.ServerEnabled = gosettings.DefaultPointer(d.ServerEnabled, true)
-	d.ServerAddress = gosettings.DefaultValidator(d.ServerAddress, localhost)
+	d.UpstreamType = gosettings.DefaultComparable(d.UpstreamType, "dot")
+	const defaultUpdatePeriod = 24 * time.Hour
+	d.UpdatePeriod = gosettings.DefaultPointer(d.UpdatePeriod, defaultUpdatePeriod)
+	d.Providers = gosettings.DefaultSlice(d.Providers, []string{
+		provider.Cloudflare().Name,
+	})
+	d.Caching = gosettings.DefaultPointer(d.Caching, true)
+	d.IPv6 = gosettings.DefaultPointer(d.IPv6, false)
+	d.Blacklist.setDefaults()
+	d.ServerAddress = gosettings.DefaultValidator(d.ServerAddress,
+		netip.AddrFrom4([4]byte{127, 0, 0, 1}))
 	d.KeepNameserver = gosettings.DefaultPointer(d.KeepNameserver, false)
-	d.DoT.setDefaults()
+}
+
+func (d DNS) GetFirstPlaintextIPv4() (ipv4 netip.Addr) {
+	localhost := netip.AddrFrom4([4]byte{127, 0, 0, 1})
+	if d.ServerAddress.Compare(localhost) != 0 && d.ServerAddress.Is4() {
+		return d.ServerAddress
+	}
+
+	providers := provider.NewProviders()
+	provider, err := providers.Get(d.Providers[0])
+	if err != nil {
+		// Settings should be validated before calling this function,
+		// so an error happening here is a programming error.
+		panic(err)
+	}
+
+	return provider.Plain.IPv4[0].Addr()
 }
 
 func (d DNS) String() string {
@@ -77,11 +160,63 @@ func (d DNS) toLinesNode() (node *gotree.Node) {
 		return node
 	}
 	node.Appendf("DNS server address to use: %s", d.ServerAddress)
-	node.AppendNode(d.DoT.toLinesNode())
+
+	node.Appendf("DNS forwarder server enabled: %s", gosettings.BoolToYesNo(d.ServerEnabled))
+	if !*d.ServerEnabled {
+		return node
+	}
+
+	node.Appendf("Upstream resolver type: %s", d.UpstreamType)
+
+	upstreamResolvers := node.Append("Upstream resolvers:")
+	for _, provider := range d.Providers {
+		upstreamResolvers.Append(provider)
+	}
+
+	node.Appendf("Caching: %s", gosettings.BoolToYesNo(d.Caching))
+	node.Appendf("IPv6: %s", gosettings.BoolToYesNo(d.IPv6))
+
+	update := "disabled"
+	if *d.UpdatePeriod > 0 {
+		update = "every " + d.UpdatePeriod.String()
+	}
+	node.Appendf("Update period: %s", update)
+
+	node.AppendNode(d.Blacklist.toLinesNode())
+
 	return node
 }
 
 func (d *DNS) read(r *reader.Reader) (err error) {
+	d.ServerEnabled, err = r.BoolPtr("DNS_SERVER", reader.RetroKeys("DOT"))
+	if err != nil {
+		return err
+	}
+
+	d.UpstreamType = r.String("DNS_UPSTREAM_RESOLVER_TYPE")
+
+	d.UpdatePeriod, err = r.DurationPtr("DNS_UPDATE_PERIOD")
+	if err != nil {
+		return err
+	}
+
+	d.Providers = r.CSV("DNS_UPSTREAM_RESOLVERS", reader.RetroKeys("DOT_PROVIDERS"))
+
+	d.Caching, err = r.BoolPtr("DNS_CACHING", reader.RetroKeys("DOT_CACHING"))
+	if err != nil {
+		return err
+	}
+
+	d.IPv6, err = r.BoolPtr("DNS_UPSTREAM_IPV6", reader.RetroKeys("DOT_IPV6"))
+	if err != nil {
+		return err
+	}
+
+	err = d.Blacklist.read(r)
+	if err != nil {
+		return err
+	}
+
 	d.ServerAddress, err = r.NetipAddr("DNS_ADDRESS", reader.RetroKeys("DNS_PLAINTEXT_ADDRESS"))
 	if err != nil {
 		return err
@@ -92,10 +227,5 @@ func (d *DNS) read(r *reader.Reader) (err error) {
 		return err
 	}
 
-	err = d.DoT.read(r)
-	if err != nil {
-		return fmt.Errorf("DNS over TLS settings: %w", err)
-	}
-
 	return nil
 }

internal/configuration/settings/dnsblacklist.go

@@ -149,23 +149,45 @@ func (b *DNSBlacklist) read(r *reader.Reader) (err error) {
 		return err
 	}
 
-	b.AddBlockedIPs, b.AddBlockedIPPrefixes,
+	b.AddBlockedIPs, b.AddBlockedIPPrefixes, err = readDNSBlockedIPs(r)
-		err = readDoTPrivateAddresses(r) // TODO v4 split in 2
 	if err != nil {
 		return err
 	}
 
-	b.AllowedHosts = r.CSV("UNBLOCK") // TODO v4 change name
+	b.AllowedHosts = r.CSV("DNS_UNBLOCK_HOSTNAMES", reader.RetroKeys("UNBLOCK"))
 
 	return nil
 }
 
-var ErrPrivateAddressNotValid = errors.New("private address is not a valid IP or CIDR range")
+func readDNSBlockedIPs(r *reader.Reader) (ips []netip.Addr,
-
-func readDoTPrivateAddresses(reader *reader.Reader) (ips []netip.Addr,
 	ipPrefixes []netip.Prefix, err error,
 ) {
-	privateAddresses := reader.CSV("DOT_PRIVATE_ADDRESS")
+	ips, err = r.CSVNetipAddresses("DNS_BLOCK_IPS")
+	if err != nil {
+		return nil, nil, err
+	}
+	ipPrefixes, err = r.CSVNetipPrefixes("DNS_BLOCK_IP_PREFIXES")
+	if err != nil {
+		return nil, nil, err
+	}
+
+	// TODO v4 remove this block below
+	privateIPs, privateIPPrefixes, err := readDNSPrivateAddresses(r)
+	if err != nil {
+		return nil, nil, err
+	}
+	ips = append(ips, privateIPs...)
+	ipPrefixes = append(ipPrefixes, privateIPPrefixes...)
+
+	return ips, ipPrefixes, nil
+}
+
+var ErrPrivateAddressNotValid = errors.New("private address is not a valid IP or CIDR range")
+
+func readDNSPrivateAddresses(r *reader.Reader) (ips []netip.Addr,
+	ipPrefixes []netip.Prefix, err error,
+) {
+	privateAddresses := r.CSV("DOT_PRIVATE_ADDRESS", reader.IsRetro("DNS_BLOCK_IP_PREFIXES"))
 	if len(privateAddresses) == 0 {
 		return nil, nil, nil
 	}

internal/configuration/settings/dot.go

@@ -1,170 +0,0 @@
-package settings
-
-import (
-	"errors"
-	"fmt"
-	"net/netip"
-	"time"
-
-	"github.com/qdm12/dns/v2/pkg/provider"
-	"github.com/qdm12/gosettings"
-	"github.com/qdm12/gosettings/reader"
-	"github.com/qdm12/gotree"
-)
-
-// DoT contains settings to configure the DoT server.
-type DoT struct {
-	// Enabled is true if the DoT server should be running
-	// and used. It defaults to true, and cannot be nil
-	// in the internal state.
-	Enabled *bool
-	// UpdatePeriod is the period to update DNS block lists.
-	// It can be set to 0 to disable the update.
-	// It defaults to 24h and cannot be nil in
-	// the internal state.
-	UpdatePeriod *time.Duration
-	// Providers is a list of DNS over TLS providers
-	Providers []string `json:"providers"`
-	// Caching is true if the DoT server should cache
-	// DNS responses.
-	Caching *bool `json:"caching"`
-	// IPv6 is true if the DoT server should connect over IPv6.
-	IPv6 *bool `json:"ipv6"`
-	// Blacklist contains settings to configure the filter
-	// block lists.
-	Blacklist DNSBlacklist
-}
-
-var ErrDoTUpdatePeriodTooShort = errors.New("update period is too short")
-
-func (d DoT) validate() (err error) {
-	const minUpdatePeriod = 30 * time.Second
-	if *d.UpdatePeriod != 0 && *d.UpdatePeriod < minUpdatePeriod {
-		return fmt.Errorf("%w: %s must be bigger than %s",
-			ErrDoTUpdatePeriodTooShort, *d.UpdatePeriod, minUpdatePeriod)
-	}
-
-	providers := provider.NewProviders()
-	for _, providerName := range d.Providers {
-		_, err := providers.Get(providerName)
-		if err != nil {
-			return err
-		}
-	}
-
-	err = d.Blacklist.validate()
-	if err != nil {
-		return err
-	}
-
-	return nil
-}
-
-func (d *DoT) copy() (copied DoT) {
-	return DoT{
-		Enabled:      gosettings.CopyPointer(d.Enabled),
-		UpdatePeriod: gosettings.CopyPointer(d.UpdatePeriod),
-		Providers:    gosettings.CopySlice(d.Providers),
-		Caching:      gosettings.CopyPointer(d.Caching),
-		IPv6:         gosettings.CopyPointer(d.IPv6),
-		Blacklist:    d.Blacklist.copy(),
-	}
-}
-
-// overrideWith overrides fields of the receiver
-// 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.Providers = gosettings.OverrideWithSlice(d.Providers, other.Providers)
-	d.Caching = gosettings.OverrideWithPointer(d.Caching, other.Caching)
-	d.IPv6 = gosettings.OverrideWithPointer(d.IPv6, other.IPv6)
-	d.Blacklist.overrideWith(other.Blacklist)
-}
-
-func (d *DoT) setDefaults() {
-	d.Enabled = gosettings.DefaultPointer(d.Enabled, true)
-	const defaultUpdatePeriod = 24 * time.Hour
-	d.UpdatePeriod = gosettings.DefaultPointer(d.UpdatePeriod, defaultUpdatePeriod)
-	d.Providers = gosettings.DefaultSlice(d.Providers, []string{
-		provider.Cloudflare().Name,
-	})
-	d.Caching = gosettings.DefaultPointer(d.Caching, true)
-	d.IPv6 = gosettings.DefaultPointer(d.IPv6, false)
-	d.Blacklist.setDefaults()
-}
-
-func (d DoT) GetFirstPlaintextIPv4() (ipv4 netip.Addr) {
-	providers := provider.NewProviders()
-	provider, err := providers.Get(d.Providers[0])
-	if err != nil {
-		// Settings should be validated before calling this function,
-		// so an error happening here is a programming error.
-		panic(err)
-	}
-
-	return provider.DoT.IPv4[0].Addr()
-}
-
-func (d DoT) String() string {
-	return d.toLinesNode().String()
-}
-
-func (d DoT) toLinesNode() (node *gotree.Node) {
-	node = gotree.New("DNS over TLS settings:")
-
-	node.Appendf("Enabled: %s", gosettings.BoolToYesNo(d.Enabled))
-	if !*d.Enabled {
-		return node
-	}
-
-	update := "disabled" //nolint:goconst
-	if *d.UpdatePeriod > 0 {
-		update = "every " + d.UpdatePeriod.String()
-	}
-	node.Appendf("Update period: %s", update)
-
-	upstreamResolvers := node.Append("Upstream resolvers:")
-	for _, provider := range d.Providers {
-		upstreamResolvers.Append(provider)
-	}
-
-	node.Appendf("Caching: %s", gosettings.BoolToYesNo(d.Caching))
-	node.Appendf("IPv6: %s", gosettings.BoolToYesNo(d.IPv6))
-
-	node.AppendNode(d.Blacklist.toLinesNode())
-
-	return node
-}
-
-func (d *DoT) read(reader *reader.Reader) (err error) {
-	d.Enabled, err = reader.BoolPtr("DOT")
-	if err != nil {
-		return err
-	}
-
-	d.UpdatePeriod, err = reader.DurationPtr("DNS_UPDATE_PERIOD")
-	if err != nil {
-		return err
-	}
-
-	d.Providers = reader.CSV("DOT_PROVIDERS")
-
-	d.Caching, err = reader.BoolPtr("DOT_CACHING")
-	if err != nil {
-		return err
-	}
-
-	d.IPv6, err = reader.BoolPtr("DOT_IPV6")
-	if err != nil {
-		return err
-	}
-
-	err = d.Blacklist.read(reader)
-	if err != nil {
-		return err
-	}
-
-	return nil
-}

internal/configuration/settings/health.go

@@ -2,6 +2,7 @@ package settings
 
 import (
 	"fmt"
+	"net/netip"
 	"os"
 	"time"
 
@@ -24,16 +25,16 @@ type Health struct {
 	// 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.
+	// to TCP TLS 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
+	// ICMPTargetIP is the IP address to use for ICMP echo requests
-	// healthcheck after a successful healthcheck.
+	// in the health checker. It can be set to an unspecified address (0.0.0.0)
-	// It defaults to 5 seconds and cannot be zero in
+	// such that the VPN server IP is used, which is also the default behavior.
-	// the internal state.
+	ICMPTargetIP netip.Addr
-	SuccessWait time.Duration
+	// RestartVPN indicates whether to restart the VPN connection
-	// VPN has health settings specific to the VPN loop.
+	// when the healthcheck fails.
-	VPN HealthyWait
+	RestartVPN *bool
 }
 
 func (h Health) Validate() (err error) {
@@ -42,11 +43,6 @@ func (h Health) Validate() (err error) {
 		return fmt.Errorf("server listening address is not valid: %w", err)
 	}
 
-	err = h.VPN.validate()
-	if err != nil {
-		return fmt.Errorf("health VPN settings: %w", err)
-	}
-
 	return nil
 }
 
@@ -56,8 +52,8 @@ func (h *Health) copy() (copied Health) {
 		ReadHeaderTimeout: h.ReadHeaderTimeout,
 		ReadTimeout:       h.ReadTimeout,
 		TargetAddress:     h.TargetAddress,
-		SuccessWait:       h.SuccessWait,
+		ICMPTargetIP:      h.ICMPTargetIP,
-		VPN:               h.VPN.copy(),
+		RestartVPN:        gosettings.CopyPointer(h.RestartVPN),
 	}
 }
 
@@ -69,8 +65,8 @@ func (h *Health) OverrideWith(other Health) {
 	h.ReadHeaderTimeout = gosettings.OverrideWithComparable(h.ReadHeaderTimeout, other.ReadHeaderTimeout)
 	h.ReadTimeout = gosettings.OverrideWithComparable(h.ReadTimeout, other.ReadTimeout)
 	h.TargetAddress = gosettings.OverrideWithComparable(h.TargetAddress, other.TargetAddress)
-	h.SuccessWait = gosettings.OverrideWithComparable(h.SuccessWait, other.SuccessWait)
+	h.ICMPTargetIP = gosettings.OverrideWithComparable(h.ICMPTargetIP, other.ICMPTargetIP)
-	h.VPN.overrideWith(other.VPN)
+	h.RestartVPN = gosettings.OverrideWithPointer(h.RestartVPN, other.RestartVPN)
 }
 
 func (h *Health) SetDefaults() {
@@ -80,9 +76,8 @@ func (h *Health) SetDefaults() {
 	const defaultReadTimeout = 500 * time.Millisecond
 	h.ReadTimeout = gosettings.DefaultComparable(h.ReadTimeout, defaultReadTimeout)
 	h.TargetAddress = gosettings.DefaultComparable(h.TargetAddress, "cloudflare.com:443")
-	const defaultSuccessWait = 5 * time.Second
+	h.ICMPTargetIP = gosettings.DefaultComparable(h.ICMPTargetIP, netip.IPv4Unspecified()) // use the VPN server IP
-	h.SuccessWait = gosettings.DefaultComparable(h.SuccessWait, defaultSuccessWait)
+	h.RestartVPN = gosettings.DefaultPointer(h.RestartVPN, true)
-	h.VPN.setDefaults()
 }
 
 func (h Health) String() string {
@@ -93,10 +88,12 @@ 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)
+	icmpTarget := "VPN server IP"
-	node.Appendf("Read header timeout: %s", h.ReadHeaderTimeout)
+	if !h.ICMPTargetIP.IsUnspecified() {
-	node.Appendf("Read timeout: %s", h.ReadTimeout)
+		icmpTarget = h.ICMPTargetIP.String()
-	node.AppendNode(h.VPN.toLinesNode("VPN"))
+	}
+	node.Appendf("ICMP target IP: %s", icmpTarget)
+	node.Appendf("Restart VPN on healthcheck failure: %s", gosettings.BoolToYesNo(h.RestartVPN))
 	return node
 }
 
@@ -104,16 +101,13 @@ func (h *Health) Read(r *reader.Reader) (err error) {
 	h.ServerAddress = r.String("HEALTH_SERVER_ADDRESS")
 	h.TargetAddress = r.String("HEALTH_TARGET_ADDRESS",
 		reader.RetroKeys("HEALTH_ADDRESS_TO_PING"))
-
+	h.ICMPTargetIP, err = r.NetipAddr("HEALTH_ICMP_TARGET_IP")
-	h.SuccessWait, err = r.Duration("HEALTH_SUCCESS_WAIT_DURATION")
 	if err != nil {
 		return err
 	}
-
+	h.RestartVPN, err = r.BoolPtr("HEALTH_RESTART_VPN")
-	err = h.VPN.read(r)
 	if err != nil {
-		return fmt.Errorf("VPN health settings: %w", err)
+		return err
 	}
-
 	return nil
 }

internal/configuration/settings/healthywait.go

@@ -1,76 +0,0 @@
-package settings
-
-import (
-	"time"
-
-	"github.com/qdm12/gosettings"
-	"github.com/qdm12/gosettings/reader"
-	"github.com/qdm12/gotree"
-)
-
-type HealthyWait struct {
-	// Initial is the initial duration to wait for the program
-	// to be healthy before taking action.
-	// It cannot be nil in the internal state.
-	Initial *time.Duration
-	// Addition is the duration to add to the Initial duration
-	// after Initial has expired to wait longer for the program
-	// to be healthy.
-	// It cannot be nil in the internal state.
-	Addition *time.Duration
-}
-
-func (h HealthyWait) validate() (err error) {
-	return nil
-}
-
-func (h *HealthyWait) copy() (copied HealthyWait) {
-	return HealthyWait{
-		Initial:  gosettings.CopyPointer(h.Initial),
-		Addition: gosettings.CopyPointer(h.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)
-}
-
-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)
-}
-
-func (h HealthyWait) String() string {
-	return h.toLinesNode("Health").String()
-}
-
-func (h HealthyWait) toLinesNode(kind string) (node *gotree.Node) {
-	node = gotree.New(kind + " wait durations:")
-	node.Appendf("Initial duration: %s", *h.Initial)
-	node.Appendf("Additional duration: %s", *h.Addition)
-	return node
-}
-
-func (h *HealthyWait) read(r *reader.Reader) (err error) {
-	h.Initial, err = r.DurationPtr(
-		"HEALTH_VPN_DURATION_INITIAL",
-		reader.RetroKeys("HEALTH_OPENVPN_DURATION_INITIAL"))
-	if err != nil {
-		return err
-	}
-
-	h.Addition, err = r.DurationPtr(
-		"HEALTH_VPN_DURATION_ADDITION",
-		reader.RetroKeys("HEALTH_OPENVPN_DURATION_ADDITION"))
-	if err != nil {
-		return err
-	}
-
-	return nil
-}

internal/configuration/settings/ipv6.go

@@ -0,0 +1,51 @@
+package settings
+
+import (
+	"net/netip"
+
+	"github.com/qdm12/gosettings"
+	"github.com/qdm12/gosettings/reader"
+	"github.com/qdm12/gotree"
+)
+
+// IPv6 contains settings regarding IPv6 configuration.
+type IPv6 struct {
+	// CheckAddress is the TCP ip:port address to dial to check
+	// IPv6 is supported, in case a default IPv6 route is found.
+	// It defaults to cloudflare.com address [2606:4700::6810:84e5]:443
+	CheckAddress netip.AddrPort
+}
+
+func (i IPv6) validate() (err error) {
+	return nil
+}
+
+func (i *IPv6) copy() (copied IPv6) {
+	return IPv6{
+		CheckAddress: i.CheckAddress,
+	}
+}
+
+func (i *IPv6) overrideWith(other IPv6) {
+	i.CheckAddress = gosettings.OverrideWithValidator(i.CheckAddress, other.CheckAddress)
+}
+
+func (i *IPv6) setDefaults() {
+	defaultCheckAddress := netip.MustParseAddrPort("[2606:4700::6810:84e5]:443")
+	i.CheckAddress = gosettings.DefaultComparable(i.CheckAddress, defaultCheckAddress)
+}
+
+func (i IPv6) String() string {
+	return i.toLinesNode().String()
+}
+
+func (i IPv6) toLinesNode() (node *gotree.Node) {
+	node = gotree.New("IPv6 settings:")
+	node.Appendf("Check address: %s", i.CheckAddress)
+	return node
+}
+
+func (i *IPv6) read(r *reader.Reader) (err error) {
+	i.CheckAddress, err = r.NetipAddrPort("IPV6_CHECK_ADDRESS")
+	return err
+}

internal/configuration/settings/serverselection.go

@@ -17,7 +17,7 @@ import (
 	"github.com/qdm12/gotree"
 )
 
-type ServerSelection struct { //nolint:maligned
+type ServerSelection struct {
 	// VPN is the VPN type which can be 'openvpn'
 	// or 'wireguard'. It cannot be the empty string
 	// in the internal state.
@@ -354,11 +354,8 @@ func (ss *ServerSelection) setDefaults(vpnProvider string, portForwardingEnabled
 	ss.SecureCoreOnly = gosettings.DefaultPointer(ss.SecureCoreOnly, false)
 	ss.TorOnly = gosettings.DefaultPointer(ss.TorOnly, false)
 	ss.MultiHopOnly = gosettings.DefaultPointer(ss.MultiHopOnly, false)
-	defaultPortForwardOnly := false
+	defaultPortForwardOnly := portForwardingEnabled &&
-	if portForwardingEnabled && helpers.IsOneOf(vpnProvider,
+		helpers.IsOneOf(vpnProvider, providers.PrivateInternetAccess, providers.Protonvpn)
-		providers.PrivateInternetAccess, providers.Protonvpn) {
-		defaultPortForwardOnly = true
-	}
 	ss.PortForwardOnly = gosettings.DefaultPointer(ss.PortForwardOnly, defaultPortForwardOnly)
 	ss.OpenVPN.setDefaults(vpnProvider)
 	ss.Wireguard.setDefaults()

internal/configuration/settings/settings.go

@@ -27,6 +27,7 @@ type Settings struct {
 	Updater       Updater
 	Version       Version
 	VPN           VPN
+	IPv6          IPv6
 	Pprof         pprof.Settings
 }
 
@@ -53,6 +54,7 @@ func (s *Settings) Validate(filterChoicesGetter FilterChoicesGetter, ipv6Support
 		"system":          s.System.validate,
 		"updater":         s.Updater.Validate,
 		"version":         s.Version.validate,
+		"ipv6":            s.IPv6.validate,
 		// Pprof validation done in pprof constructor
 		"VPN": func() error {
 			return s.VPN.Validate(filterChoicesGetter, ipv6Supported, warner)
@@ -85,6 +87,7 @@ func (s *Settings) copy() (copied Settings) {
 		Version:       s.Version.copy(),
 		VPN:           s.VPN.Copy(),
 		Pprof:         s.Pprof.Copy(),
+		IPv6:          s.IPv6.copy(),
 	}
 }
 
@@ -106,6 +109,7 @@ func (s *Settings) OverrideWith(other Settings,
 	patchedSettings.Version.overrideWith(other.Version)
 	patchedSettings.VPN.OverrideWith(other.VPN)
 	patchedSettings.Pprof.OverrideWith(other.Pprof)
+	patchedSettings.IPv6.overrideWith(other.IPv6)
 	err = patchedSettings.Validate(filterChoicesGetter, ipv6Supported, warner)
 	if err != nil {
 		return err
@@ -121,6 +125,7 @@ func (s *Settings) SetDefaults() {
 	s.Health.SetDefaults()
 	s.HTTPProxy.setDefaults()
 	s.Log.setDefaults()
+	s.IPv6.setDefaults()
 	s.PublicIP.setDefaults()
 	s.Shadowsocks.setDefaults()
 	s.Storage.setDefaults()
@@ -142,6 +147,7 @@ func (s Settings) toLinesNode() (node *gotree.Node) {
 	node.AppendNode(s.DNS.toLinesNode())
 	node.AppendNode(s.Firewall.toLinesNode())
 	node.AppendNode(s.Log.toLinesNode())
+	node.AppendNode(s.IPv6.toLinesNode())
 	node.AppendNode(s.Health.toLinesNode())
 	node.AppendNode(s.Shadowsocks.toLinesNode())
 	node.AppendNode(s.HTTPProxy.toLinesNode())
@@ -177,10 +183,10 @@ func (s Settings) Warnings() (warnings []string) {
 	// TODO remove in v4
 	if s.DNS.ServerAddress.Unmap().Compare(netip.AddrFrom4([4]byte{127, 0, 0, 1})) != 0 {
 		warnings = append(warnings, "DNS address is set to "+s.DNS.ServerAddress.String()+
-			" so the DNS over TLS (DoT) server will not be used."+
+			" so the local forwarding DNS 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 DNS server."+
-			" If the DoT server fails to start, the IPv4 address of the first plaintext DNS server"+
+			" If this server fails to start, the IPv4 address of the first plaintext DNS server"+
-			" corresponding to the first DoT provider chosen is used.")
+			" corresponding to the first DNS provider chosen is used.")
 	}
 
 	return warnings
@@ -208,6 +214,7 @@ func (s *Settings) Read(r *reader.Reader, warner Warner) (err error) {
 		"updater":     s.Updater.read,
 		"version":     s.Version.read,
 		"VPN":         s.VPN.read,
+		"IPv6":        s.IPv6.read,
 		"profiling":   s.Pprof.Read,
 	}
 

internal/configuration/settings/settings_test.go

@@ -40,30 +40,28 @@ func Test_Settings_String(t *testing.T) {
 ├── DNS settings:
 |   ├── Keep existing nameserver(s): no
 |   ├── DNS server address to use: 127.0.0.1
-|   └── DNS over TLS settings:
+|   ├── DNS forwarder server enabled: yes
-|       ├── Enabled: yes
+|   ├── Upstream resolver type: dot
-|       ├── Update period: every 24h0m0s
+|   ├── Upstream resolvers:
-|       ├── Upstream resolvers:
+|   |   └── Cloudflare
-|       |   └── Cloudflare
+|   ├── Caching: yes
-|       ├── Caching: yes
+|   ├── IPv6: no
-|       ├── IPv6: no
+|   ├── Update period: every 24h0m0s
-|       └── DNS filtering settings:
+|   └── DNS filtering settings:
-|           ├── Block malicious: yes
+|       ├── Block malicious: yes
-|           ├── Block ads: no
+|       ├── Block ads: no
-|           └── Block surveillance: yes
+|       └── Block surveillance: yes
 ├── Firewall settings:
 |   └── Enabled: yes
 ├── Log settings:
 |   └── Log level: INFO
+├── IPv6 settings:
+|   └── Check address: [2606:4700::6810:84e5]:443
 ├── Health settings:
 |   ├── Server listening address: 127.0.0.1:9999
 |   ├── Target address: cloudflare.com:443
-|   ├── Duration to wait after success: 5s
+|   ├── ICMP target IP: VPN server IP
-|   ├── Read header timeout: 100ms
+|   └── Restart VPN on healthcheck failure: yes
-|   ├── Read timeout: 500ms
-|   └── VPN wait durations:
-|       ├── Initial duration: 6s
-|       └── Additional duration: 5s
 ├── Shadowsocks server settings:
 |   └── Enabled: no
 ├── HTTP proxy settings:

internal/configuration/settings/shadowsocks.go

@@ -15,7 +15,7 @@ type Shadowsocks struct {
 	// It defaults to false, and cannot be nil in the internal state.
 	Enabled *bool
 	// Settings are settings for the TCP+UDP server.
-	tcpudp.Settings
+	Settings tcpudp.Settings
 }
 
 func (s Shadowsocks) validate() (err error) {

internal/dns/plaintext.go

@@ -10,15 +10,7 @@ import (
 func (l *Loop) useUnencryptedDNS(fallback bool) {
 	settings := l.GetSettings()
 
-	// Try with user provided plaintext ip address
+	targetIP := settings.GetFirstPlaintextIPv4()
-	// if it's not 127.0.0.1 (default for DoT), otherwise
-	// use the first DoT provider ipv4 address found.
-	var targetIP netip.Addr
-	if settings.ServerAddress.Compare(netip.AddrFrom4([4]byte{127, 0, 0, 1})) != 0 {
-		targetIP = settings.ServerAddress
-	} else {
-		targetIP = settings.DoT.GetFirstPlaintextIPv4()
-	}
 
 	if fallback {
 		l.logger.Info("falling back on plaintext DNS at address " + targetIP.String())
@@ -27,14 +19,15 @@ func (l *Loop) useUnencryptedDNS(fallback bool) {
 	}
 
 	const dialTimeout = 3 * time.Second
+	const defaultDNSPort = 53
 	settingsInternalDNS := nameserver.SettingsInternalDNS{
-		IP:      targetIP,
+		AddrPort: netip.AddrPortFrom(targetIP, defaultDNSPort),
-		Timeout: dialTimeout,
+		Timeout:  dialTimeout,
 	}
 	nameserver.UseDNSInternally(settingsInternalDNS)
 
 	settingsSystemWide := nameserver.SettingsSystemDNS{
-		IP:         targetIP,
+		IPs:        []netip.Addr{targetIP},
 		ResolvPath: l.resolvConf,
 	}
 	err := nameserver.UseDNSSystemWide(settingsSystemWide)

internal/dns/run.go

@@ -26,12 +26,12 @@ func (l *Loop) Run(ctx context.Context, done chan<- struct{}) {
 	}
 
 	for ctx.Err() == nil {
-		// Upper scope variables for the DNS over TLS server only
+		// Upper scope variables for the DNS forwarder server only
 		// Their values are to be used if DOT=off
 		var runError <-chan error
 
 		settings := l.GetSettings()
-		for !*settings.KeepNameserver && *settings.DoT.Enabled {
+		for !*settings.KeepNameserver && *settings.ServerEnabled {
 			var err error
 			runError, err = l.setupServer(ctx)
 			if err == nil {
@@ -56,7 +56,7 @@ func (l *Loop) Run(ctx context.Context, done chan<- struct{}) {
 		}
 
 		settings = l.GetSettings()
-		if !*settings.KeepNameserver && !*settings.DoT.Enabled {
+		if !*settings.KeepNameserver && !*settings.ServerEnabled {
 			const fallback = false
 			l.useUnencryptedDNS(fallback)
 		}
@@ -101,6 +101,6 @@ func (l *Loop) runWait(ctx context.Context, runError <-chan error) (exitLoop boo
 func (l *Loop) stopServer() {
 	stopErr := l.server.Stop()
 	if stopErr != nil {
-		l.logger.Error("stopping DoT server: " + stopErr.Error())
+		l.logger.Error("stopping server: " + stopErr.Error())
 	}
 }

internal/dns/settings.go

@@ -4,11 +4,13 @@ import (
 	"context"
 	"fmt"
 
+	"github.com/qdm12/dns/v2/pkg/doh"
 	"github.com/qdm12/dns/v2/pkg/dot"
 	cachemiddleware "github.com/qdm12/dns/v2/pkg/middlewares/cache"
 	"github.com/qdm12/dns/v2/pkg/middlewares/cache/lru"
 	filtermiddleware "github.com/qdm12/dns/v2/pkg/middlewares/filter"
 	"github.com/qdm12/dns/v2/pkg/middlewares/filter/mapfilter"
+	"github.com/qdm12/dns/v2/pkg/plain"
 	"github.com/qdm12/dns/v2/pkg/provider"
 	"github.com/qdm12/dns/v2/pkg/server"
 	"github.com/qdm12/gluetun/internal/configuration/settings"
@@ -22,33 +24,62 @@ func (l *Loop) SetSettings(ctx context.Context, settings settings.DNS) (
 	return l.state.SetSettings(ctx, settings)
 }
 
-func buildDoTSettings(settings settings.DNS,
+func buildServerSettings(settings settings.DNS,
 	filter *mapfilter.Filter, logger Logger) (
 	serverSettings server.Settings, err error,
 ) {
 	serverSettings.Logger = logger
 
-	var dotSettings dot.Settings
 	providersData := provider.NewProviders()
-	dotSettings.UpstreamResolvers = make([]provider.Provider, len(settings.DoT.Providers))
+	upstreamResolvers := make([]provider.Provider, len(settings.Providers))
-	for i := range settings.DoT.Providers {
+	for i := range settings.Providers {
 		var err error
-		dotSettings.UpstreamResolvers[i], err = providersData.Get(settings.DoT.Providers[i])
+		upstreamResolvers[i], err = providersData.Get(settings.Providers[i])
 		if err != nil {
 			panic(err) // this should already had been checked
 		}
 	}
-	dotSettings.IPVersion = "ipv4"
+
-	if *settings.DoT.IPv6 {
+	ipVersion := "ipv4"
-		dotSettings.IPVersion = "ipv6"
+	if *settings.IPv6 {
+		ipVersion = "ipv6"
 	}
 
-	serverSettings.Dialer, err = dot.New(dotSettings)
+	var dialer server.Dialer
-	if err != nil {
+	switch settings.UpstreamType {
-		return server.Settings{}, fmt.Errorf("creating DNS over TLS dialer: %w", err)
+	case "dot":
+		dialerSettings := dot.Settings{
+			UpstreamResolvers: upstreamResolvers,
+			IPVersion:         ipVersion,
+		}
+		dialer, err = dot.New(dialerSettings)
+		if err != nil {
+			return server.Settings{}, fmt.Errorf("creating DNS over TLS dialer: %w", err)
+		}
+	case "doh":
+		dialerSettings := doh.Settings{
+			UpstreamResolvers: upstreamResolvers,
+			IPVersion:         ipVersion,
+		}
+		dialer, err = doh.New(dialerSettings)
+		if err != nil {
+			return server.Settings{}, fmt.Errorf("creating DNS over HTTPS dialer: %w", err)
+		}
+	case "plain":
+		dialerSettings := plain.Settings{
+			UpstreamResolvers: upstreamResolvers,
+			IPVersion:         ipVersion,
+		}
+		dialer, err = plain.New(dialerSettings)
+		if err != nil {
+			return server.Settings{}, fmt.Errorf("creating plain DNS dialer: %w", err)
+		}
+	default:
+		panic("unknown upstream type: " + settings.UpstreamType)
 	}
+	serverSettings.Dialer = dialer
 
-	if *settings.DoT.Caching {
+	if *settings.Caching {
 		lruCache, err := lru.New(lru.Settings{})
 		if err != nil {
 			return server.Settings{}, fmt.Errorf("creating LRU cache: %w", err)

internal/dns/setup.go

@@ -4,6 +4,7 @@ import (
 	"context"
 	"errors"
 	"fmt"
+	"net/netip"
 
 	"github.com/qdm12/dns/v2/pkg/check"
 	"github.com/qdm12/dns/v2/pkg/nameserver"
@@ -20,14 +21,14 @@ func (l *Loop) setupServer(ctx context.Context) (runError <-chan error, err erro
 
 	settings := l.GetSettings()
 
-	dotSettings, err := buildDoTSettings(settings, l.filter, l.logger)
+	serverSettings, err := buildServerSettings(settings, l.filter, l.logger)
 	if err != nil {
-		return nil, fmt.Errorf("building DoT settings: %w", err)
+		return nil, fmt.Errorf("building server settings: %w", err)
 	}
 
-	server, err := server.New(dotSettings)
+	server, err := server.New(serverSettings)
 	if err != nil {
-		return nil, fmt.Errorf("creating DoT server: %w", err)
+		return nil, fmt.Errorf("creating server: %w", err)
 	}
 
 	runError, err = server.Start(ctx)
@@ -37,11 +38,12 @@ func (l *Loop) setupServer(ctx context.Context) (runError <-chan error, err erro
 	l.server = server
 
 	// use internal DNS server
+	const defaultDNSPort = 53
 	nameserver.UseDNSInternally(nameserver.SettingsInternalDNS{
-		IP: settings.ServerAddress,
+		AddrPort: netip.AddrPortFrom(settings.ServerAddress, defaultDNSPort),
 	})
 	err = nameserver.UseDNSSystemWide(nameserver.SettingsSystemDNS{
-		IP:         settings.ServerAddress,
+		IPs:        []netip.Addr{settings.ServerAddress},
 		ResolvPath: l.resolvConf,
 	})
 	if err != nil {

internal/dns/state/settings.go

@@ -27,7 +27,7 @@ func (s *State) SetSettings(ctx context.Context, settings settings.DNS) (
 
 	// Check for only update period change
 	tempSettings := s.settings.Copy()
-	*tempSettings.DoT.UpdatePeriod = *settings.DoT.UpdatePeriod
+	*tempSettings.UpdatePeriod = *settings.UpdatePeriod
 	onlyUpdatePeriodChanged := reflect.DeepEqual(tempSettings, settings)
 
 	s.settings = settings
@@ -40,7 +40,7 @@ func (s *State) SetSettings(ctx context.Context, settings settings.DNS) (
 
 	// Restart
 	_, _ = s.statusApplier.ApplyStatus(ctx, constants.Stopped)
-	if *settings.DoT.Enabled {
+	if *settings.ServerEnabled {
 		outcome, _ = s.statusApplier.ApplyStatus(ctx, constants.Running)
 	}
 	return outcome

internal/dns/ticker.go

@@ -14,7 +14,7 @@ func (l *Loop) RunRestartTicker(ctx context.Context, done chan<- struct{}) {
 	timer.Stop()
 	timerIsStopped := true
 	settings := l.GetSettings()
-	if period := *settings.DoT.UpdatePeriod; period > 0 {
+	if period := *settings.UpdatePeriod; period > 0 {
 		timer.Reset(period)
 		timerIsStopped = false
 	}
@@ -43,14 +43,14 @@ func (l *Loop) RunRestartTicker(ctx context.Context, done chan<- struct{}) {
 			_, _ = l.statusManager.ApplyStatus(ctx, constants.Running)
 
 			settings := l.GetSettings()
-			timer.Reset(*settings.DoT.UpdatePeriod)
+			timer.Reset(*settings.UpdatePeriod)
 		case <-l.updateTicker:
 			if !timer.Stop() {
 				<-timer.C
 			}
 			timerIsStopped = true
 			settings := l.GetSettings()
-			newUpdatePeriod := *settings.DoT.UpdatePeriod
+			newUpdatePeriod := *settings.UpdatePeriod
 			if newUpdatePeriod == 0 {
 				continue
 			}

internal/dns/update.go

@@ -12,7 +12,7 @@ func (l *Loop) updateFiles(ctx context.Context) (err error) {
 	settings := l.GetSettings()
 
 	l.logger.Info("downloading hostnames and IP block lists")
-	blacklistSettings := settings.DoT.Blacklist.ToBlockBuilderSettings(l.client)
+	blacklistSettings := settings.Blacklist.ToBlockBuilderSettings(l.client)
 
 	blockBuilder, err := blockbuilder.New(blacklistSettings)
 	if err != nil {

internal/firewall/delete.go

@@ -16,7 +16,7 @@ func isDeleteMatchInstruction(instruction string) bool {
 	fields := strings.Fields(instruction)
 	for i, field := range fields {
 		switch {
-		case field != "-D" && field != "--delete": //nolint:goconst
+		case field != "-D" && field != "--delete":
 			continue
 		case i == len(fields)-1: // malformed: missing chain name
 			return false

internal/firewall/firewall.go

@@ -9,7 +9,7 @@ import (
 	"github.com/qdm12/gluetun/internal/routing"
 )
 
-type Config struct { //nolint:maligned
+type Config struct {
 	runner         CmdRunner
 	logger         Logger
 	iptablesMutex  sync.Mutex

internal/firewall/ip6tables.go

@@ -58,7 +58,7 @@ var ErrPolicyNotValid = errors.New("policy is not valid")
 
 func (c *Config) setIPv6AllPolicies(ctx context.Context, policy string) error {
 	switch policy {
-	case "ACCEPT", "DROP": //nolint:goconst
+	case "ACCEPT", "DROP":
 	default:
 		return fmt.Errorf("%w: %s", ErrPolicyNotValid, policy)
 	}

internal/firewall/iptables.go

@@ -149,7 +149,7 @@ func (c *Config) acceptOutputTrafficToVPN(ctx context.Context,
 ) error {
 	protocol := connection.Protocol
 	if protocol == "tcp-client" {
-		protocol = "tcp" //nolint:goconst
+		protocol = "tcp"
 	}
 	instruction := fmt.Sprintf("%s OUTPUT -d %s -o %s -p %s -m %s --dport %d -j ACCEPT",
 		appendOrDelete(remove), connection.IP, defaultInterface, protocol,
@@ -162,6 +162,24 @@ func (c *Config) acceptOutputTrafficToVPN(ctx context.Context,
 	return c.runIP6tablesInstruction(ctx, instruction)
 }
 
+func (c *Config) AcceptOutput(ctx context.Context,
+	protocol, intf string, ip netip.Addr, port uint16, remove bool,
+) error {
+	interfaceFlag := "-o " + intf
+	if intf == "*" { // all interfaces
+		interfaceFlag = ""
+	}
+
+	instruction := fmt.Sprintf("%s OUTPUT -d %s %s -p %s -m %s --dport %d -j ACCEPT",
+		appendOrDelete(remove), ip, interfaceFlag, protocol, protocol, port)
+	if ip.Is4() {
+		return c.runIptablesInstruction(ctx, instruction)
+	} else if c.ip6Tables == "" {
+		return fmt.Errorf("accept output to VPN server: %w", ErrNeedIP6Tables)
+	}
+	return c.runIP6tablesInstruction(ctx, instruction)
+}
+
 // Thanks to @npawelek.
 func (c *Config) acceptOutputFromIPToSubnet(ctx context.Context,
 	intf string, sourceIP netip.Addr, destinationSubnet netip.Prefix, remove bool,

internal/firewall/list.go

@@ -323,12 +323,12 @@ var ErrProtocolUnknown = errors.New("unknown protocol")
 
 func parseProtocol(s string) (protocol string, err error) {
 	switch s {
-	case "0":
+	case "0", "all":
-	case "1":
+	case "1", "icmp":
 		protocol = "icmp"
-	case "6":
+	case "6", "tcp":
 		protocol = "tcp"
-	case "17":
+	case "17", "udp":
 		protocol = "udp"
 	default:
 		return "", fmt.Errorf("%w: %s", ErrProtocolUnknown, s)

internal/firewall/list_test.go

@@ -58,6 +58,7 @@ num pkts bytes target     prot opt in     out     source               destinati
 2   0     0 ACCEPT     6    --  tun0   *       0.0.0.0/0            0.0.0.0/0            tcp dpt:55405
 3   0     0 ACCEPT     1    --  tun0   *       0.0.0.0/0            0.0.0.0/0
 4   0     0 DROP       0    --  tun0   *       1.2.3.4              0.0.0.0/0
+5   0     0 ACCEPT     all  --  tun0   *       1.2.3.4              0.0.0.0/0
 `,
 			table: chain{
 				name:    "INPUT",
@@ -111,6 +112,17 @@ num pkts bytes target     prot opt in     out     source               destinati
 						source:          netip.MustParsePrefix("1.2.3.4/32"),
 						destination:     netip.MustParsePrefix("0.0.0.0/0"),
 					},
+					{
+						lineNumber:      5,
+						packets:         0,
+						bytes:           0,
+						target:          "ACCEPT",
+						protocol:        "",
+						inputInterface:  "tun0",
+						outputInterface: "*",
+						source:          netip.MustParsePrefix("1.2.3.4/32"),
+						destination:     netip.MustParsePrefix("0.0.0.0/0"),
+					},
 				},
 			},
 		},

internal/healthcheck/checker.go

@@ -0,0 +1,250 @@
+package healthcheck
+
+import (
+	"context"
+	"crypto/tls"
+	"errors"
+	"fmt"
+	"net"
+	"net/netip"
+	"strings"
+	"sync"
+	"time"
+
+	"github.com/qdm12/gluetun/internal/healthcheck/dns"
+	"github.com/qdm12/gluetun/internal/healthcheck/icmp"
+)
+
+type Checker struct {
+	tlsDialAddr string
+	dialer      *net.Dialer
+	echoer      *icmp.Echoer
+	dnsClient   *dns.Client
+	logger      Logger
+	icmpTarget  netip.Addr
+	configMutex sync.Mutex
+
+	icmpNotPermitted bool
+	smallCheckName   string
+
+	// Internal periodic service signals
+	stop context.CancelFunc
+	done <-chan struct{}
+}
+
+func NewChecker(logger Logger) *Checker {
+	return &Checker{
+		dialer: &net.Dialer{
+			Resolver: &net.Resolver{
+				PreferGo: true,
+			},
+		},
+		echoer:    icmp.NewEchoer(logger),
+		dnsClient: dns.New(),
+		logger:    logger,
+	}
+}
+
+// SetConfig sets the TCP+TLS dial address and the ICMP echo IP address
+// to target by the [Checker].
+// This function MUST be called before calling [Checker.Start].
+func (c *Checker) SetConfig(tlsDialAddr string, icmpTarget netip.Addr) {
+	c.configMutex.Lock()
+	defer c.configMutex.Unlock()
+	c.tlsDialAddr = tlsDialAddr
+	c.icmpTarget = icmpTarget
+}
+
+// Start starts the checker by first running a blocking 2s-timed TCP+TLS check,
+// and, on success, starts the periodic checks in a separate goroutine:
+// - a "small" ICMP echo check every 15 seconds
+// - a "full" TCP+TLS check every 5 minutes
+// It returns a channel `runError` that receives an error (nil or not) when a periodic check is performed.
+// It returns an error if the initial TCP+TLS check fails.
+// The Checker has to be ultimately stopped by calling [Checker.Stop].
+func (c *Checker) Start(ctx context.Context) (runError <-chan error, err error) {
+	if c.tlsDialAddr == "" || c.icmpTarget.IsUnspecified() {
+		panic("call Checker.SetConfig with non empty values before Checker.Start")
+	}
+
+	// connection isn't under load yet when the checker starts, so a short
+	// 6 seconds timeout suffices and provides quick enough feedback that
+	// the new connection is not working.
+	const timeout = 6 * time.Second
+	tcpTLSCheckCtx, tcpTLSCheckCancel := context.WithTimeout(ctx, timeout)
+	err = tcpTLSCheck(tcpTLSCheckCtx, c.dialer, c.tlsDialAddr)
+	tcpTLSCheckCancel()
+	if err != nil {
+		return nil, fmt.Errorf("startup check: %w", err)
+	}
+
+	ready := make(chan struct{})
+	ctx, cancel := context.WithCancel(context.Background())
+	c.stop = cancel
+	done := make(chan struct{})
+	c.done = done
+	c.smallCheckName = "ICMP echo"
+	const smallCheckPeriod = time.Minute
+	smallCheckTimer := time.NewTimer(smallCheckPeriod)
+	const fullCheckPeriod = 5 * time.Minute
+	fullCheckTimer := time.NewTimer(fullCheckPeriod)
+	runErrorCh := make(chan error)
+	runError = runErrorCh
+	go func() {
+		defer close(done)
+		close(ready)
+		for {
+			select {
+			case <-ctx.Done():
+				fullCheckTimer.Stop()
+				smallCheckTimer.Stop()
+				return
+			case <-smallCheckTimer.C:
+				err := c.smallPeriodicCheck(ctx)
+				if err != nil {
+					err = fmt.Errorf("small periodic check: %w", err)
+				}
+				runErrorCh <- err
+				smallCheckTimer.Reset(smallCheckPeriod)
+			case <-fullCheckTimer.C:
+				err := c.fullPeriodicCheck(ctx)
+				if err != nil {
+					err = fmt.Errorf("full periodic check: %w", err)
+				}
+				runErrorCh <- err
+				fullCheckTimer.Reset(fullCheckPeriod)
+			}
+		}
+	}()
+	<-ready
+	return runError, nil
+}
+
+func (c *Checker) Stop() error {
+	c.stop()
+	<-c.done
+	c.icmpTarget = netip.Addr{}
+	return nil
+}
+
+func (c *Checker) smallPeriodicCheck(ctx context.Context) error {
+	c.configMutex.Lock()
+	ip := c.icmpTarget
+	c.configMutex.Unlock()
+	const maxTries = 3
+	const timeout = 10 * time.Second
+	const extraTryTime = 10 * time.Second // 10s added for each subsequent retry
+	check := func(ctx context.Context) error {
+		if c.icmpNotPermitted {
+			return c.dnsClient.Check(ctx)
+		}
+		err := c.echoer.Echo(ctx, ip)
+		if errors.Is(err, icmp.ErrNotPermitted) {
+			c.icmpNotPermitted = true
+			c.smallCheckName = "plain DNS over UDP"
+			c.logger.Infof("%s; permanently falling back to %s checks.", c.smallCheckName, err)
+			return c.dnsClient.Check(ctx)
+		}
+		return err
+	}
+	return withRetries(ctx, maxTries, timeout, extraTryTime, c.logger, c.smallCheckName, check)
+}
+
+func (c *Checker) fullPeriodicCheck(ctx context.Context) error {
+	const maxTries = 2
+	// 20s timeout in case the connection is under stress
+	// See https://github.com/qdm12/gluetun/issues/2270
+	const timeout = 20 * time.Second
+	const extraTryTime = 10 * time.Second // 10s added for each subsequent retry
+	check := func(ctx context.Context) error {
+		return tcpTLSCheck(ctx, c.dialer, c.tlsDialAddr)
+	}
+	return withRetries(ctx, maxTries, timeout, extraTryTime, c.logger, "TCP+TLS dial", check)
+}
+
+func tcpTLSCheck(ctx context.Context, dialer *net.Dialer, targetAddress string) error {
+	// TODO use mullvad API if current provider is Mullvad
+
+	address, err := makeAddressToDial(targetAddress)
+	if err != nil {
+		return err
+	}
+
+	const dialNetwork = "tcp4"
+	connection, err := dialer.DialContext(ctx, dialNetwork, address)
+	if err != nil {
+		return fmt.Errorf("dialing: %w", err)
+	}
+
+	if strings.HasSuffix(address, ":443") {
+		host, _, err := net.SplitHostPort(address)
+		if err != nil {
+			return fmt.Errorf("splitting host and port: %w", err)
+		}
+		tlsConfig := &tls.Config{
+			MinVersion: tls.VersionTLS12,
+			ServerName: host,
+		}
+		tlsConnection := tls.Client(connection, tlsConfig)
+		err = tlsConnection.HandshakeContext(ctx)
+		if err != nil {
+			return fmt.Errorf("running TLS handshake: %w", err)
+		}
+	}
+
+	err = connection.Close()
+	if err != nil {
+		return fmt.Errorf("closing connection: %w", err)
+	}
+
+	return nil
+}
+
+func makeAddressToDial(address string) (addressToDial string, err error) {
+	host, port, err := net.SplitHostPort(address)
+	if err != nil {
+		addrErr := new(net.AddrError)
+		ok := errors.As(err, &addrErr)
+		if !ok || addrErr.Err != "missing port in address" {
+			return "", fmt.Errorf("splitting host and port from address: %w", err)
+		}
+		host = address
+		const defaultPort = "443"
+		port = defaultPort
+	}
+	address = net.JoinHostPort(host, port)
+	return address, nil
+}
+
+var ErrAllCheckTriesFailed = errors.New("all check tries failed")
+
+func withRetries(ctx context.Context, maxTries uint, tryTimeout, extraTryTime time.Duration,
+	logger Logger, checkName string, check func(ctx context.Context) error,
+) error {
+	try := uint(0)
+	var errs []error
+	for {
+		timeout := tryTimeout + time.Duration(try)*extraTryTime //nolint:gosec
+		checkCtx, cancel := context.WithTimeout(ctx, timeout)
+		err := check(checkCtx)
+		cancel()
+		switch {
+		case err == nil:
+			return nil
+		case ctx.Err() != nil:
+			return fmt.Errorf("%s: %w", checkName, ctx.Err())
+		}
+		logger.Debugf("%s attempt %d/%d failed: %s", checkName, try+1, maxTries, err)
+		errs = append(errs, err)
+		try++
+		if try < maxTries {
+			continue
+		}
+		errStrings := make([]string, len(errs))
+		for i, err := range errs {
+			errStrings[i] = fmt.Sprintf("attempt %d: %s", i+1, err.Error())
+		}
+		return fmt.Errorf("%w: after %d %s attempts (%s)",
+			ErrAllCheckTriesFailed, maxTries, checkName, strings.Join(errStrings, "; "))
+	}
+}

internal/healthcheck/checker_test.go

@@ -7,12 +7,11 @@ import (
 	"testing"
 	"time"
 
-	"github.com/qdm12/gluetun/internal/configuration/settings"
 	"github.com/stretchr/testify/assert"
 	"github.com/stretchr/testify/require"
 )
 
-func Test_Server_healthCheck(t *testing.T) {
+func Test_Checker_fullcheck(t *testing.T) {
 	t.Parallel()
 
 	t.Run("canceled real dialer", func(t *testing.T) {
@@ -21,26 +20,28 @@ func Test_Server_healthCheck(t *testing.T) {
 		dialer := &net.Dialer{}
 		const address = "cloudflare.com:443"
 
-		server := &Server{
+		checker := &Checker{
-			dialer: dialer,
+			dialer:      dialer,
-			config: settings.Health{
+			tlsDialAddr: address,
-				TargetAddress: address,
-			},
 		}
 
 		canceledCtx, cancel := context.WithCancel(context.Background())
 		cancel()
 
-		err := server.healthCheck(canceledCtx)
+		err := checker.fullPeriodicCheck(canceledCtx)
 
 		require.Error(t, err)
-		assert.Contains(t, err.Error(), "operation was canceled")
+		assert.EqualError(t, err, "TCP+TLS dial: context canceled")
 	})
 
 	t.Run("dial localhost:0", func(t *testing.T) {
 		t.Parallel()
 
-		listener, err := net.Listen("tcp4", "localhost:0")
+		const timeout = 100 * time.Millisecond
+		ctx, cancel := context.WithTimeout(context.Background(), timeout)
+		defer cancel()
+		listenConfig := &net.ListenConfig{}
+		listener, err := listenConfig.Listen(ctx, "tcp4", "localhost:0")
 		require.NoError(t, err)
 		t.Cleanup(func() {
 			err = listener.Close()
@@ -50,18 +51,12 @@ func Test_Server_healthCheck(t *testing.T) {
 		listeningAddress := listener.Addr()
 
 		dialer := &net.Dialer{}
-		server := &Server{
+		checker := &Checker{
-			dialer: dialer,
+			dialer:      dialer,
-			config: settings.Health{
+			tlsDialAddr: listeningAddress.String(),
-				TargetAddress: listeningAddress.String(),
-			},
 		}
 
-		const timeout = 100 * time.Millisecond
+		err = checker.fullPeriodicCheck(ctx)
-		ctx, cancel := context.WithTimeout(context.Background(), timeout)
-		defer cancel()
-
-		err = server.healthCheck(ctx)
 
 		assert.NoError(t, err)
 	})

internal/healthcheck/dns/dns.go

@@ -0,0 +1,66 @@
+package dns
+
+import (
+	"context"
+	"errors"
+	"fmt"
+	"net"
+	"net/netip"
+
+	"github.com/qdm12/dns/v2/pkg/provider"
+)
+
+// Client is a simple plaintext UDP DNS client, to be used for healthchecks.
+// Note the client connects to a DNS server only over UDP on port 53,
+// because we don't want to use DoT or DoH and impact the TCP connections
+// when running a healthcheck.
+type Client struct {
+	serverAddrs []netip.AddrPort
+	dnsIPIndex  int
+}
+
+func New() *Client {
+	return &Client{
+		serverAddrs: concatAddrPorts([][]netip.AddrPort{
+			provider.Cloudflare().Plain.IPv4,
+			provider.Google().Plain.IPv4,
+			provider.Quad9().Plain.IPv4,
+			provider.OpenDNS().Plain.IPv4,
+			provider.LibreDNS().Plain.IPv4,
+			provider.Quadrant().Plain.IPv4,
+			provider.CiraProtected().Plain.IPv4,
+		}),
+	}
+}
+
+func concatAddrPorts(addrs [][]netip.AddrPort) []netip.AddrPort {
+	var result []netip.AddrPort
+	for _, addrList := range addrs {
+		result = append(result, addrList...)
+	}
+	return result
+}
+
+var ErrLookupNoIPs = errors.New("no IPs found from DNS lookup")
+
+func (c *Client) Check(ctx context.Context) error {
+	dnsAddr := c.serverAddrs[c.dnsIPIndex].Addr()
+	resolver := &net.Resolver{
+		PreferGo: true,
+		Dial: func(ctx context.Context, _, _ string) (net.Conn, error) {
+			dialer := net.Dialer{}
+			return dialer.DialContext(ctx, "udp", dnsAddr.String())
+		},
+	}
+	ips, err := resolver.LookupIP(ctx, "ip", "github.com")
+	switch {
+	case err != nil:
+		c.dnsIPIndex = (c.dnsIPIndex + 1) % len(c.serverAddrs)
+		return err
+	case len(ips) == 0:
+		c.dnsIPIndex = (c.dnsIPIndex + 1) % len(c.serverAddrs)
+		return fmt.Errorf("%w", ErrLookupNoIPs)
+	default:
+		return nil
+	}
+}

internal/healthcheck/handler.go

@@ -9,13 +9,15 @@ import (
 type handler struct {
 	healthErr   error
 	healthErrMu sync.RWMutex
+	logger      Logger
 }
 
 var errHealthcheckNotRunYet = errors.New("healthcheck did not run yet")
 
-func newHandler() *handler {
+func newHandler(logger Logger) *handler {
 	return &handler{
 		healthErr: errHealthcheckNotRunYet,
+		logger:    logger,
 	}
 }
 

internal/healthcheck/health.go

@@ -1,122 +0,0 @@
-package healthcheck
-
-import (
-	"context"
-	"crypto/tls"
-	"errors"
-	"fmt"
-	"net"
-	"strings"
-	"time"
-)
-
-func (s *Server) runHealthcheckLoop(ctx context.Context, done chan<- struct{}) {
-	defer close(done)
-
-	timeoutIndex := 0
-	healthcheckTimeouts := []time.Duration{
-		2 * time.Second,
-		4 * time.Second,
-		6 * time.Second,
-		8 * time.Second,
-		// This can be useful when the connection is under stress
-		// See https://github.com/qdm12/gluetun/issues/2270
-		10 * time.Second,
-	}
-	s.vpn.healthyTimer = time.NewTimer(s.vpn.healthyWait)
-
-	for {
-		previousErr := s.handler.getErr()
-
-		timeout := healthcheckTimeouts[timeoutIndex]
-		healthcheckCtx, healthcheckCancel := context.WithTimeout(
-			ctx, timeout)
-		err := s.healthCheck(healthcheckCtx)
-		healthcheckCancel()
-
-		s.handler.setErr(err)
-
-		switch {
-		case previousErr != nil && err == nil: // First success
-			s.logger.Info("healthy!")
-			timeoutIndex = 0
-			s.vpn.healthyTimer.Stop()
-			s.vpn.healthyWait = *s.config.VPN.Initial
-		case previousErr == nil && err != nil: // First failure
-			s.logger.Debug("unhealthy: " + err.Error())
-			s.vpn.healthyTimer.Stop()
-			s.vpn.healthyTimer = time.NewTimer(s.vpn.healthyWait)
-		case previousErr != nil && err != nil: // Nth failure
-			if timeoutIndex < len(healthcheckTimeouts)-1 {
-				timeoutIndex++
-			}
-			select {
-			case <-s.vpn.healthyTimer.C:
-				timeoutIndex = 0 // retry next with the smallest timeout
-				s.onUnhealthyVPN(ctx, err.Error())
-			default:
-			}
-		case previousErr == nil && err == nil: // Nth success
-			timer := time.NewTimer(s.config.SuccessWait)
-			select {
-			case <-ctx.Done():
-				return
-			case <-timer.C:
-			}
-		}
-	}
-}
-
-func (s *Server) healthCheck(ctx context.Context) (err error) {
-	// TODO use mullvad API if current provider is Mullvad
-
-	address, err := makeAddressToDial(s.config.TargetAddress)
-	if err != nil {
-		return err
-	}
-
-	const dialNetwork = "tcp4"
-	connection, err := s.dialer.DialContext(ctx, dialNetwork, address)
-	if err != nil {
-		return fmt.Errorf("dialing: %w", err)
-	}
-
-	if strings.HasSuffix(address, ":443") {
-		host, _, err := net.SplitHostPort(address)
-		if err != nil {
-			return fmt.Errorf("splitting host and port: %w", err)
-		}
-		tlsConfig := &tls.Config{
-			MinVersion: tls.VersionTLS12,
-			ServerName: host,
-		}
-		tlsConnection := tls.Client(connection, tlsConfig)
-		err = tlsConnection.HandshakeContext(ctx)
-		if err != nil {
-			return fmt.Errorf("running TLS handshake: %w", err)
-		}
-	}
-
-	err = connection.Close()
-	if err != nil {
-		return fmt.Errorf("closing connection: %w", err)
-	}
-
-	return nil
-}
-
-func makeAddressToDial(address string) (addressToDial string, err error) {
-	host, port, err := net.SplitHostPort(address)
-	if err != nil {
-		addrErr := new(net.AddrError)
-		ok := errors.As(err, &addrErr)
-		if !ok || addrErr.Err != "missing port in address" {
-			return "", fmt.Errorf("splitting host and port from address: %w", err)
-		}
-		host = address
-		const defaultPort = "443"
-		port = defaultPort
-	}
-	address = net.JoinHostPort(host, port)
-	return address, nil
-}

internal/healthcheck/icmp/apple_ipv4.go

@@ -0,0 +1,49 @@
+package icmp
+
+import (
+	"net"
+	"time"
+
+	"golang.org/x/net/ipv4"
+)
+
+var _ net.PacketConn = &ipv4Wrapper{}
+
+// ipv4Wrapper is a wrapper around ipv4.PacketConn to implement
+// the net.PacketConn interface. It's only used for Darwin or iOS.
+type ipv4Wrapper struct {
+	ipv4Conn *ipv4.PacketConn
+}
+
+func ipv4ToNetPacketConn(ipv4 *ipv4.PacketConn) *ipv4Wrapper {
+	return &ipv4Wrapper{ipv4Conn: ipv4}
+}
+
+func (i *ipv4Wrapper) ReadFrom(p []byte) (n int, addr net.Addr, err error) {
+	n, _, addr, err = i.ipv4Conn.ReadFrom(p)
+	return n, addr, err
+}
+
+func (i *ipv4Wrapper) WriteTo(p []byte, addr net.Addr) (n int, err error) {
+	return i.ipv4Conn.WriteTo(p, nil, addr)
+}
+
+func (i *ipv4Wrapper) Close() error {
+	return i.ipv4Conn.Close()
+}
+
+func (i *ipv4Wrapper) LocalAddr() net.Addr {
+	return i.ipv4Conn.LocalAddr()
+}
+
+func (i *ipv4Wrapper) SetDeadline(t time.Time) error {
+	return i.ipv4Conn.SetDeadline(t)
+}
+
+func (i *ipv4Wrapper) SetReadDeadline(t time.Time) error {
+	return i.ipv4Conn.SetReadDeadline(t)
+}
+
+func (i *ipv4Wrapper) SetWriteDeadline(t time.Time) error {
+	return i.ipv4Conn.SetWriteDeadline(t)
+}

internal/healthcheck/icmp/echo.go

@@ -0,0 +1,193 @@
+package icmp
+
+import (
+	"bytes"
+	"context"
+	cryptorand "crypto/rand"
+	"encoding/binary"
+	"errors"
+	"fmt"
+	"io"
+	"math/rand/v2"
+	"net"
+	"net/netip"
+	"strings"
+
+	"golang.org/x/net/icmp"
+	"golang.org/x/net/ipv4"
+	"golang.org/x/net/ipv6"
+)
+
+var (
+	ErrICMPBodyUnsupported  = errors.New("ICMP body type is not supported")
+	ErrICMPEchoDataMismatch = errors.New("ICMP data mismatch")
+)
+
+type Echoer struct {
+	buffer       []byte
+	randomSource io.Reader
+	logger       Logger
+}
+
+func NewEchoer(logger Logger) *Echoer {
+	const maxICMPEchoSize = 1500
+	buffer := make([]byte, maxICMPEchoSize)
+	var seed [32]byte
+	_, _ = cryptorand.Read(seed[:])
+	randomSource := rand.NewChaCha8(seed)
+	return &Echoer{
+		buffer:       buffer,
+		randomSource: randomSource,
+		logger:       logger,
+	}
+}
+
+var (
+	ErrTimedOut     = errors.New("timed out waiting for ICMP echo reply")
+	ErrNotPermitted = errors.New("not permitted")
+)
+
+func (i *Echoer) Echo(ctx context.Context, ip netip.Addr) (err error) {
+	var ipVersion string
+	var conn net.PacketConn
+	if ip.Is4() {
+		ipVersion = "v4"
+		conn, err = listenICMPv4(ctx)
+	} else {
+		ipVersion = "v6"
+		conn, err = listenICMPv6(ctx)
+	}
+	if err != nil {
+		if strings.HasSuffix(err.Error(), "socket: operation not permitted") {
+			err = fmt.Errorf("%w: you can try adding NET_RAW capability to resolve this", ErrNotPermitted)
+		}
+		return fmt.Errorf("listening for ICMP packets: %w", err)
+	}
+
+	go func() {
+		<-ctx.Done()
+		conn.Close()
+	}()
+
+	const echoDataSize = 32
+	id, message := buildMessageToSend(ipVersion, echoDataSize, i.randomSource)
+
+	encodedMessage, err := message.Marshal(nil)
+	if err != nil {
+		return fmt.Errorf("encoding ICMP message: %w", err)
+	}
+
+	_, err = conn.WriteTo(encodedMessage, &net.IPAddr{IP: ip.AsSlice()})
+	if err != nil {
+		if strings.HasSuffix(err.Error(), "sendto: operation not permitted") {
+			err = fmt.Errorf("%w", ErrNotPermitted)
+		}
+		return fmt.Errorf("writing ICMP message: %w", err)
+	}
+
+	receivedData, err := receiveEchoReply(conn, id, i.buffer, ipVersion, i.logger)
+	if err != nil {
+		if errors.Is(err, net.ErrClosed) && ctx.Err() != nil {
+			return fmt.Errorf("%w", ErrTimedOut)
+		}
+		return fmt.Errorf("receiving ICMP echo reply: %w", err)
+	}
+
+	sentData := message.Body.(*icmp.Echo).Data //nolint:forcetypeassert
+	if !bytes.Equal(receivedData, sentData) {
+		return fmt.Errorf("%w: sent %x and received %x", ErrICMPEchoDataMismatch, sentData, receivedData)
+	}
+
+	return nil
+}
+
+func buildMessageToSend(ipVersion string, size uint, randomSource io.Reader) (id int, message *icmp.Message) {
+	const uint16Bytes = 2
+	idBytes := make([]byte, uint16Bytes)
+	_, _ = randomSource.Read(idBytes)
+	id = int(binary.BigEndian.Uint16(idBytes))
+
+	var icmpType icmp.Type
+	switch ipVersion {
+	case "v4":
+		icmpType = ipv4.ICMPTypeEcho
+	case "v6":
+		icmpType = ipv6.ICMPTypeEchoRequest
+	default:
+		panic(fmt.Sprintf("IP version %q not supported", ipVersion))
+	}
+	messageBodyData := make([]byte, size)
+	_, _ = randomSource.Read(messageBodyData)
+
+	// See https://www.iana.org/assignments/icmp-parameters/icmp-parameters.xhtml#icmp-parameters-types
+	message = &icmp.Message{
+		Type:     icmpType, // echo request
+		Code:     0,        // no code
+		Checksum: 0,        // calculated at encoding (ipv4) or sending (ipv6)
+		Body: &icmp.Echo{
+			ID:   id,
+			Seq:  0, // only one packet
+			Data: messageBodyData,
+		},
+	}
+	return id, message
+}
+
+func receiveEchoReply(conn net.PacketConn, id int, buffer []byte, ipVersion string, logger Logger,
+) (data []byte, err error) {
+	var icmpProtocol int
+	const (
+		icmpv4Protocol = 1
+		icmpv6Protocol = 58
+	)
+	switch ipVersion {
+	case "v4":
+		icmpProtocol = icmpv4Protocol
+	case "v6":
+		icmpProtocol = icmpv6Protocol
+	default:
+		panic(fmt.Sprintf("unknown IP version: %s", ipVersion))
+	}
+
+	for {
+		// Note we need to read the whole packet in one call to ReadFrom, so the buffer
+		// must be large enough to read the entire reply packet. See:
+		// https://groups.google.com/g/golang-nuts/c/5dy2Q4nPs08/m/KmuSQAGEtG4J
+		bytesRead, returnAddr, err := conn.ReadFrom(buffer)
+		if err != nil {
+			return nil, fmt.Errorf("reading from ICMP connection: %w", err)
+		}
+		packetBytes := buffer[:bytesRead]
+
+		// Parse the ICMP message
+		message, err := icmp.ParseMessage(icmpProtocol, packetBytes)
+		if err != nil {
+			return nil, fmt.Errorf("parsing message: %w", err)
+		}
+
+		switch body := message.Body.(type) {
+		case *icmp.Echo:
+			if id != body.ID {
+				logger.Warnf("ignoring ICMP echo reply mismatching expected id %d "+
+					"(id: %d, type: %d, code: %d, length: %d, return address %s)",
+					id, body.ID, message.Type, message.Code, len(packetBytes), returnAddr)
+				continue // not the ID we are looking for
+			}
+			return body.Data, nil
+		case *icmp.DstUnreach:
+			logger.Debugf("ignoring ICMP destination unreachable message (type: 3, code: %d, return address %s, expected-id %d)",
+				message.Code, returnAddr, id)
+			// See https://github.com/qdm12/gluetun/pull/2923#issuecomment-3377532249
+			// on why we ignore this message. If it is actually unreachable, the timeout on waiting for
+			// the echo reply will do instead of returning an error error.
+			continue
+		case *icmp.TimeExceeded:
+			logger.Debugf("ignoring ICMP time exceeded message (type: 11, code: %d, return address %s, expected-id %d)",
+				message.Code, returnAddr, id)
+			continue
+		default:
+			return nil, fmt.Errorf("%w: %T (type %d, code %d, return address %s, expected-id %d)",
+				ErrICMPBodyUnsupported, body, message.Type, message.Code, returnAddr, id)
+		}
+	}
+}

internal/healthcheck/icmp/interfaces.go

@@ -0,0 +1,6 @@
+package icmp
+
+type Logger interface {
+	Debugf(format string, args ...any)
+	Warnf(format string, args ...any)
+}

internal/healthcheck/icmp/listen.go

@@ -0,0 +1,35 @@
+package icmp
+
+import (
+	"context"
+	"fmt"
+	"net"
+	"runtime"
+
+	"golang.org/x/net/ipv4"
+)
+
+func listenICMPv4(ctx context.Context) (conn net.PacketConn, err error) {
+	var listenConfig net.ListenConfig
+	const listenAddress = ""
+	packetConn, err := listenConfig.ListenPacket(ctx, "ip4:icmp", listenAddress)
+	if err != nil {
+		return nil, fmt.Errorf("listening for ICMP packets: %w", err)
+	}
+
+	if runtime.GOOS == "darwin" || runtime.GOOS == "ios" {
+		packetConn = ipv4ToNetPacketConn(ipv4.NewPacketConn(packetConn))
+	}
+
+	return packetConn, nil
+}
+
+func listenICMPv6(ctx context.Context) (conn net.PacketConn, err error) {
+	var listenConfig net.ListenConfig
+	const listenAddress = ""
+	packetConn, err := listenConfig.ListenPacket(ctx, "ip6:ipv6-icmp", listenAddress)
+	if err != nil {
+		return nil, fmt.Errorf("listening for ICMPv6 packets: %w", err)
+	}
+	return packetConn, nil
+}

internal/healthcheck/interfaces.go

@@ -0,0 +1,9 @@
+package healthcheck
+
+type Logger interface {
+	Debugf(format string, args ...any)
+	Info(s string)
+	Infof(format string, args ...any)
+	Warnf(format string, args ...any)
+	Error(s string)
+}

internal/healthcheck/logger.go

@@ -1,7 +0,0 @@
-package healthcheck
-
-type Logger interface {
-	Debug(s string)
-	Info(s string)
-	Error(s string)
-}

internal/healthcheck/openvpn.go

@@ -1,25 +0,0 @@
-package healthcheck
-
-import (
-	"context"
-	"time"
-
-	"github.com/qdm12/gluetun/internal/constants"
-)
-
-type vpnHealth struct {
-	loop         StatusApplier
-	healthyWait  time.Duration
-	healthyTimer *time.Timer
-}
-
-func (s *Server) onUnhealthyVPN(ctx context.Context, lastErrMessage string) {
-	s.logger.Info("program has been unhealthy for " +
-		s.vpn.healthyWait.String() + ": restarting VPN (healthcheck error: " + lastErrMessage + ")")
-	s.logger.Info("👉 See https://github.com/qdm12/gluetun-wiki/blob/main/faq/healthcheck.md")
-	s.logger.Info("DO NOT OPEN AN ISSUE UNLESS YOU READ AND TRIED EACH POSSIBLE SOLUTION")
-	_, _ = s.vpn.loop.ApplyStatus(ctx, constants.Stopped)
-	_, _ = s.vpn.loop.ApplyStatus(ctx, constants.Running)
-	s.vpn.healthyWait += *s.config.VPN.Addition
-	s.vpn.healthyTimer = time.NewTimer(s.vpn.healthyWait)
-}

internal/healthcheck/run.go

@@ -10,9 +10,6 @@ import (
 func (s *Server) Run(ctx context.Context, done chan<- struct{}) {
 	defer close(done)
 
-	loopDone := make(chan struct{})
-	go s.runHealthcheckLoop(ctx, loopDone)
-
 	server := http.Server{
 		Addr:              s.config.ServerAddress,
 		Handler:           s.handler,
@@ -37,6 +34,5 @@ func (s *Server) Run(ctx context.Context, done chan<- struct{}) {
 		s.logger.Error(err.Error())
 	}
 
-	<-loopDone
 	<-serverDone
 }

internal/healthcheck/server.go

@@ -2,7 +2,6 @@ package healthcheck
 
 import (
 	"context"
-	"net"
 
 	"github.com/qdm12/gluetun/internal/configuration/settings"
 	"github.com/qdm12/gluetun/internal/models"
@@ -11,30 +10,21 @@ import (
 type Server struct {
 	logger  Logger
 	handler *handler
-	dialer  *net.Dialer
 	config  settings.Health
-	vpn     vpnHealth
 }
 
-func NewServer(config settings.Health,
+func NewServer(config settings.Health, logger Logger) *Server {
-	logger Logger, vpnLoop StatusApplier,
-) *Server {
 	return &Server{
 		logger:  logger,
-		handler: newHandler(),
+		handler: newHandler(logger),
-		dialer: &net.Dialer{
+		config:  config,
-			Resolver: &net.Resolver{
-				PreferGo: true,
-			},
-		},
-		config: config,
-		vpn: vpnHealth{
-			loop:        vpnLoop,
-			healthyWait: *config.VPN.Initial,
-		},
 	}
 }
 
+func (s *Server) SetError(err error) {
+	s.handler.setErr(err)
+}
+
 type StatusApplier interface {
 	ApplyStatus(ctx context.Context, status models.LoopStatus) (
 		outcome string, err error)

internal/httpserver/run.go

@@ -20,8 +20,10 @@ func (s *Server) Run(ctx context.Context, ready chan<- struct{}, done chan<- str
 
 	crashed := make(chan struct{})
 	shutdownDone := make(chan struct{})
+	listenCtx, listenCancel := context.WithCancel(ctx)
 	go func() {
 		defer close(shutdownDone)
+		defer listenCancel()
 		select {
 		case <-ctx.Done():
 		case <-crashed:
@@ -37,7 +39,8 @@ func (s *Server) Run(ctx context.Context, ready chan<- struct{}, done chan<- str
 		}
 	}()
 
-	listener, err := net.Listen("tcp", s.address)
+	listenConfig := &net.ListenConfig{}
+	listener, err := listenConfig.Listen(listenCtx, "tcp", s.address)
 	if err != nil {
 		close(s.addressSet)
 		close(crashed) // stop shutdown goroutine

internal/mod/load.go

@@ -76,9 +76,9 @@ func initModule(path string) (err error) {
 		const flags = 0
 		err = unix.FinitModule(int(file.Fd()), moduleParams, flags)
 		switch {
-		case err == nil, err == unix.EEXIST: //nolint:goerr113
+		case err == nil, err == unix.EEXIST: //nolint:err113
 			return nil
-		case err != unix.ENOSYS: //nolint:goerr113
+		case err != unix.ENOSYS: //nolint:err113
 			if strings.HasSuffix(err.Error(), "operation not permitted") {
 				err = fmt.Errorf("%w; did you set the SYS_MODULE capability to your container?", err)
 			}

internal/netlink/family.go

@@ -13,7 +13,7 @@ const (
 func FamilyToString(family int) string {
 	switch family {
 	case FamilyAll:
-		return "all" //nolint:goconst
+		return "all"
 	case FamilyV4:
 		return "v4"
 	case FamilyV6:

internal/netlink/interfaces.go

@@ -1,9 +1,19 @@
 package netlink
 
-import "github.com/qdm12/log"
+import (
+	"context"
+	"net/netip"
+
+	"github.com/qdm12/log"
+)
 
 type DebugLogger interface {
 	Debug(message string)
 	Debugf(format string, args ...any)
 	Patch(options ...log.Option)
 }
+
+type Firewall interface {
+	AcceptOutput(ctx context.Context, protocol, intf string, ip netip.Addr,
+		port uint16, remove bool) (err error)
+}

internal/netlink/ipv6.go

@@ -1,37 +1,106 @@
 package netlink
 
 import (
+	"context"
 	"fmt"
+	"net"
+	"net/netip"
+	"time"
 )
 
-func (n *NetLink) IsIPv6Supported() (supported bool, err error) {
+type IPv6SupportLevel uint8
+
+const (
+	IPv6Unsupported = iota
+	// IPv6Supported indicates the host supports IPv6 but has no access to the
+	// Internet via IPv6. It is true if one IPv6 route is found and no default
+	// IPv6 route is found.
+	IPv6Supported
+	// IPv6Internet indicates the host has access to the Internet via IPv6,
+	// which is detected when a default IPv6 route is found.
+	IPv6Internet
+)
+
+func (i IPv6SupportLevel) IsSupported() bool {
+	return i == IPv6Supported || i == IPv6Internet
+}
+
+func (n *NetLink) FindIPv6SupportLevel(ctx context.Context,
+	checkAddress netip.AddrPort, firewall Firewall,
+) (level IPv6SupportLevel, err error) {
 	routes, err := n.RouteList(FamilyV6)
 	if err != nil {
-		return false, fmt.Errorf("listing IPv6 routes: %w", err)
+		return IPv6Unsupported, fmt.Errorf("listing IPv6 routes: %w", err)
 	}
 
 	// Check each route for IPv6 due to Podman bug listing IPv4 routes
 	// as IPv6 routes at container start, see:
 	// https://github.com/qdm12/gluetun/issues/1241#issuecomment-1333405949
+	level = IPv6Unsupported
 	for _, route := range routes {
 		link, err := n.LinkByIndex(route.LinkIndex)
 		if err != nil {
-			return false, fmt.Errorf("finding link corresponding to route: %w", err)
+			return IPv6Unsupported, fmt.Errorf("finding link corresponding to route: %w", err)
 		}
 
-		sourceIsIPv6 := route.Src.IsValid() && route.Src.Is6()
+		sourceIsIPv4 := route.Src.IsValid() && route.Src.Is4()
+		destinationIsIPv4 := route.Dst.IsValid() && route.Dst.Addr().Is4()
 		destinationIsIPv6 := route.Dst.IsValid() && route.Dst.Addr().Is6()
 		switch {
-		case !sourceIsIPv6 && !destinationIsIPv6,
+		case sourceIsIPv4 && destinationIsIPv4,
 			destinationIsIPv6 && route.Dst.Addr().IsLoopback():
-			continue
+		case route.Dst.Addr().IsUnspecified(): // default ipv6 route
+			n.debugLogger.Debugf("IPv6 default route found on link %s", link.Name)
+			err = dialAddrThroughFirewall(ctx, link.Name, checkAddress, firewall)
+			if err != nil {
+				n.debugLogger.Debugf("IPv6 query failed on %s: %w", link.Name, err)
+				level = IPv6Supported
+				continue
+			}
+			n.debugLogger.Debugf("IPv6 internet is accessible through link %s", link.Name)
+			return IPv6Internet, nil
+		default: // non-default ipv6 route found
+			n.debugLogger.Debugf("IPv6 is supported by link %s", link.Name)
+			level = IPv6Supported
 		}
-
-		n.debugLogger.Debugf("IPv6 is supported by link %s", link.Name)
-		return true, nil
 	}
 
-	n.debugLogger.Debugf("IPv6 is not supported after searching %d routes",
+	if level == IPv6Unsupported {
-		len(routes))
+		n.debugLogger.Debugf("no IPv6 route found in %d routes", len(routes))
-	return false, nil
+	}
+	return level, nil
+}
+
+func dialAddrThroughFirewall(ctx context.Context, intf string,
+	checkAddress netip.AddrPort, firewall Firewall,
+) (err error) {
+	const protocol = "tcp"
+	remove := false
+	err = firewall.AcceptOutput(ctx, protocol, intf,
+		checkAddress.Addr(), checkAddress.Port(), remove)
+	if err != nil {
+		return fmt.Errorf("accepting output traffic: %w", err)
+	}
+	defer func() {
+		remove = true
+		firewallErr := firewall.AcceptOutput(ctx, protocol, intf,
+			checkAddress.Addr(), checkAddress.Port(), remove)
+		if err == nil && firewallErr != nil {
+			err = fmt.Errorf("removing output traffic rule: %w", firewallErr)
+		}
+	}()
+
+	dialer := &net.Dialer{
+		Timeout: time.Second,
+	}
+	conn, err := dialer.DialContext(ctx, protocol, checkAddress.String())
+	if err != nil {
+		return fmt.Errorf("dialing: %w", err)
+	}
+	err = conn.Close()
+	if err != nil {
+		return fmt.Errorf("closing connection: %w", err)
+	}
+
+	return nil
 }

internal/netlink/ipv6_test.go

@@ -0,0 +1,167 @@
+package netlink
+
+import (
+	"context"
+	"errors"
+	"net"
+	"net/netip"
+	"strings"
+	"testing"
+	"time"
+
+	gomock "github.com/golang/mock/gomock"
+	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
+)
+
+func isIPv6LocallySupported() bool {
+	dialer := net.Dialer{Timeout: time.Millisecond}
+	_, err := dialer.Dial("tcp6", "[::1]:9999")
+	return !strings.HasSuffix(err.Error(), "connect: cannot assign requested address")
+}
+
+// Susceptible to TOCTOU but it should be fine for the use case.
+func findAvailableTCPPort(t *testing.T) (port uint16) {
+	t.Helper()
+
+	config := &net.ListenConfig{}
+	listener, err := config.Listen(context.Background(), "tcp", "localhost:0")
+	require.NoError(t, err)
+
+	addr := listener.Addr().String()
+	err = listener.Close()
+	require.NoError(t, err)
+
+	addrPort, err := netip.ParseAddrPort(addr)
+	require.NoError(t, err)
+
+	return addrPort.Port()
+}
+
+func Test_dialAddrThroughFirewall(t *testing.T) {
+	t.Parallel()
+
+	errTest := errors.New("test error")
+
+	const ipv6InternetWorks = false
+
+	testCases := map[string]struct {
+		getIPv6CheckAddr  func(t *testing.T) netip.AddrPort
+		firewallAddErr    error
+		firewallRemoveErr error
+		errMessageRegex   func() string
+	}{
+		"cloudflare.com": {
+			getIPv6CheckAddr: func(_ *testing.T) netip.AddrPort {
+				return netip.MustParseAddrPort("[2606:4700::6810:84e5]:443")
+			},
+			errMessageRegex: func() string {
+				if ipv6InternetWorks {
+					return ""
+				}
+				return "dialing: dial tcp \\[2606:4700::6810:84e5\\]:443: " +
+					"connect: (cannot assign requested address|network is unreachable)"
+			},
+		},
+		"local_server": {
+			getIPv6CheckAddr: func(t *testing.T) netip.AddrPort {
+				t.Helper()
+
+				network := "tcp6"
+				loopback := netip.MustParseAddr("::1")
+				if !isIPv6LocallySupported() {
+					network = "tcp4"
+					loopback = netip.MustParseAddr("127.0.0.1")
+				}
+
+				listener, err := net.ListenTCP(network, nil)
+				require.NoError(t, err)
+				t.Cleanup(func() {
+					err := listener.Close()
+					require.NoError(t, err)
+				})
+				addrPort := netip.MustParseAddrPort(listener.Addr().String())
+				return netip.AddrPortFrom(loopback, addrPort.Port())
+			},
+		},
+		"no_local_server": {
+			getIPv6CheckAddr: func(t *testing.T) netip.AddrPort {
+				t.Helper()
+
+				loopback := netip.MustParseAddr("::1")
+				if !ipv6InternetWorks {
+					loopback = netip.MustParseAddr("127.0.0.1")
+				}
+
+				availablePort := findAvailableTCPPort(t)
+				return netip.AddrPortFrom(loopback, availablePort)
+			},
+			errMessageRegex: func() string {
+				return "dialing: dial tcp (\\[::1\\]|127\\.0\\.0\\.1):[1-9][0-9]{1,4}: " +
+					"connect: connection refused"
+			},
+		},
+		"firewall_add_error": {
+			firewallAddErr: errTest,
+			errMessageRegex: func() string {
+				return "accepting output traffic: test error"
+			},
+		},
+		"firewall_remove_error": {
+			getIPv6CheckAddr: func(t *testing.T) netip.AddrPort {
+				t.Helper()
+
+				network := "tcp4"
+				loopback := netip.MustParseAddr("127.0.0.1")
+				listener, err := net.ListenTCP(network, nil)
+				require.NoError(t, err)
+				t.Cleanup(func() {
+					err := listener.Close()
+					require.NoError(t, err)
+				})
+				addrPort := netip.MustParseAddrPort(listener.Addr().String())
+				return netip.AddrPortFrom(loopback, addrPort.Port())
+			},
+			firewallRemoveErr: errTest,
+			errMessageRegex: func() string {
+				return "removing output traffic rule: test error"
+			},
+		},
+	}
+
+	for name, testCase := range testCases {
+		t.Run(name, func(t *testing.T) {
+			t.Parallel()
+			ctrl := gomock.NewController(t)
+
+			var checkAddr netip.AddrPort
+			if testCase.getIPv6CheckAddr != nil {
+				checkAddr = testCase.getIPv6CheckAddr(t)
+			}
+
+			ctx := context.Background()
+			const intf = "eth0"
+			firewall := NewMockFirewall(ctrl)
+			call := firewall.EXPECT().AcceptOutput(ctx, "tcp", intf,
+				checkAddr.Addr(), checkAddr.Port(), false).
+				Return(testCase.firewallAddErr)
+			if testCase.firewallAddErr == nil {
+				firewall.EXPECT().AcceptOutput(ctx, "tcp", intf,
+					checkAddr.Addr(), checkAddr.Port(), true).
+					Return(testCase.firewallRemoveErr).After(call)
+			}
+
+			err := dialAddrThroughFirewall(ctx, intf, checkAddr, firewall)
+			var errMessageRegex string
+			if testCase.errMessageRegex != nil {
+				errMessageRegex = testCase.errMessageRegex()
+			}
+			if errMessageRegex == "" {
+				assert.NoError(t, err)
+			} else {
+				require.Error(t, err)
+				assert.Regexp(t, errMessageRegex, err.Error())
+			}
+		})
+	}
+}

internal/netlink/mocks_generate_test.go

@@ -0,0 +1,3 @@
+package netlink
+
+//go:generate mockgen -destination=mocks_test.go -package=$GOPACKAGE . Firewall

internal/netlink/mocks_test.go

@@ -0,0 +1,50 @@
+// Code generated by MockGen. DO NOT EDIT.
+// Source: github.com/qdm12/gluetun/internal/netlink (interfaces: Firewall)
+
+// Package netlink is a generated GoMock package.
+package netlink
+
+import (
+	context "context"
+	netip "net/netip"
+	reflect "reflect"
+
+	gomock "github.com/golang/mock/gomock"
+)
+
+// MockFirewall is a mock of Firewall interface.
+type MockFirewall struct {
+	ctrl     *gomock.Controller
+	recorder *MockFirewallMockRecorder
+}
+
+// MockFirewallMockRecorder is the mock recorder for MockFirewall.
+type MockFirewallMockRecorder struct {
+	mock *MockFirewall
+}
+
+// NewMockFirewall creates a new mock instance.
+func NewMockFirewall(ctrl *gomock.Controller) *MockFirewall {
+	mock := &MockFirewall{ctrl: ctrl}
+	mock.recorder = &MockFirewallMockRecorder{mock}
+	return mock
+}
+
+// EXPECT returns an object that allows the caller to indicate expected use.
+func (m *MockFirewall) EXPECT() *MockFirewallMockRecorder {
+	return m.recorder
+}
+
+// AcceptOutput mocks base method.
+func (m *MockFirewall) AcceptOutput(arg0 context.Context, arg1, arg2 string, arg3 netip.Addr, arg4 uint16, arg5 bool) error {
+	m.ctrl.T.Helper()
+	ret := m.ctrl.Call(m, "AcceptOutput", arg0, arg1, arg2, arg3, arg4, arg5)
+	ret0, _ := ret[0].(error)
+	return ret0
+}
+
+// AcceptOutput indicates an expected call of AcceptOutput.
+func (mr *MockFirewallMockRecorder) AcceptOutput(arg0, arg1, arg2, arg3, arg4, arg5 interface{}) *gomock.Call {
+	mr.mock.ctrl.T.Helper()
+	return mr.mock.ctrl.RecordCallWithMethodType(mr.mock, "AcceptOutput", reflect.TypeOf((*MockFirewall)(nil).AcceptOutput), arg0, arg1, arg2, arg3, arg4, arg5)
+}

internal/portforward/service/stop.go

@@ -3,7 +3,6 @@ package service
 import (
 	"context"
 	"fmt"
-	"os"
 	"time"
 )
 
@@ -61,10 +60,10 @@ func (s *Service) cleanup() (err error) {
 	s.ports = nil
 
 	filepath := s.settings.Filepath
-	s.logger.Info("removing port file " + filepath)
+	s.logger.Info("clearing port file " + filepath)
-	err = os.Remove(filepath)
+	err = s.writePortForwardedFile(nil)
 	if err != nil {
-		return fmt.Errorf("removing port file: %w", err)
+		return fmt.Errorf("clearing port file: %w", err)
 	}
 
 	return nil

internal/provider/cyberghost/provider.go

@@ -15,12 +15,12 @@ type Provider struct {
 }
 
 func New(storage common.Storage, randSource rand.Source,
-	parallelResolver common.ParallelResolver,
+	updaterWarner common.Warner, parallelResolver common.ParallelResolver,
 ) *Provider {
 	return &Provider{
 		storage:    storage,
 		randSource: randSource,
-		Fetcher:    updater.New(parallelResolver),
+		Fetcher:    updater.New(parallelResolver, updaterWarner),
 	}
 }
 

internal/provider/cyberghost/updater/servers.go

@@ -16,7 +16,10 @@ func (u *Updater) FetchServers(ctx context.Context, minServers int) (
 
 	possibleHosts := possibleServers.hostsSlice()
 	resolveSettings := parallelResolverSettings(possibleHosts)
-	hostToIPs, _, err := u.parallelResolver.Resolve(ctx, resolveSettings)
+	hostToIPs, warnings, err := u.parallelResolver.Resolve(ctx, resolveSettings)
+	for _, warning := range warnings {
+		u.warner.Warn(warning)
+	}
 	if err != nil {
 		return nil, err
 	}

internal/provider/cyberghost/updater/updater.go

@@ -6,10 +6,12 @@ import (
 
 type Updater struct {
 	parallelResolver common.ParallelResolver
+	warner           common.Warner
 }
 
-func New(parallelResolver common.ParallelResolver) *Updater {
+func New(parallelResolver common.ParallelResolver, warner common.Warner) *Updater {
 	return &Updater{
 		parallelResolver: parallelResolver,
+		warner:           warner,
 	}
 }

internal/provider/expressvpn/updater/hardcoded.go

@@ -4,7 +4,6 @@ import (
 	"github.com/qdm12/gluetun/internal/models"
 )
 
-//nolint:lll
 func hardcodedServers() (servers []models.Server) {
 	return []models.Server{
 		{Country: "Albania", Hostname: "albania-ca-version-2.expressnetw.com"},
@@ -12,69 +11,83 @@ func hardcodedServers() (servers []models.Server) {
 		{Country: "Andorra", Hostname: "andorra-ca-version-2.expressnetw.com"},
 		{Country: "Argentina", Hostname: "argentina-ca-version-2.expressnetw.com"},
 		{Country: "Armenia", Hostname: "armenia-ca-version-2.expressnetw.com"},
+		{Country: "Australia", City: "Adelaide", Hostname: "australia-adelaide--ca-version-2.expressnetw.com"},
 		{Country: "Australia", City: "Brisbane", Hostname: "australia-brisbane-ca-version-2.expressnetw.com"},
 		{Country: "Australia", City: "Melbourne", Hostname: "australia-melbourne-ca-version-2.expressnetw.com"},
 		{Country: "Australia", City: "Perth", Hostname: "australia-perth-ca-version-2.expressnetw.com"},
 		{Country: "Australia", City: "Sydney", Hostname: "australia-sydney-2-ca-version-2.expressnetw.com"},
 		{Country: "Australia", City: "Sydney", Hostname: "australia-sydney-ca-version-2.expressnetw.com"},
+		{Country: "Australia", City: "Woolloomooloo", Hostname: "australia-woolloomooloo-2-ca-version-2.expressnetw.com"},
 		{Country: "Austria", Hostname: "austria-ca-version-2.expressnetw.com"},
+		{Country: "Azerbaijan", Hostname: "azerbaijan-ca-version-2.expressnetw.com"},
 		{Country: "Bahamas", Hostname: "bahamas-ca-version-2.expressnetw.com"},
 		{Country: "Bangladesh", Hostname: "bangladesh-ca-version-2.expressnetw.com"},
 		{Country: "Belarus", Hostname: "belarus-ca-version-2.expressnetw.com"},
 		{Country: "Belgium", Hostname: "belgium-ca-version-2.expressnetw.com"},
+		{Country: "Bermuda", Hostname: "bermuda-ca-version-2.expressnetw.com"},
 		{Country: "Bhutan", Hostname: "bhutan-ca-version-2.expressnetw.com"},
-		{Country: "Bosnia And Herzegovina", City: "Bosnia And Herzegovina", Hostname: "bosniaandherzegovina-ca-version-2.expressnetw.com"},
+		{Country: "Bolivia", Hostname: "bolivia-ca-version-2.expressnetw.com"},
+		{Country: "Bosnia and Herzegovina", Hostname: "bosniaandherzegovina-ca-version-2.expressnetw.com"},
 		{Country: "Brazil", Hostname: "brazil-2-ca-version-2.expressnetw.com"},
 		{Country: "Brazil", Hostname: "brazil-ca-version-2.expressnetw.com"},
 		{Country: "Brunei", Hostname: "brunei-ca-version-2.expressnetw.com"},
+		{Country: "Bulgaria", Hostname: "bulgaria-ca-version-2.expressnetw.com"},
 		{Country: "Cambodia", Hostname: "cambodia-ca-version-2.expressnetw.com"},
 		{Country: "Canada", City: "Montreal", Hostname: "canada-montreal-ca-version-2.expressnetw.com"},
-		{Country: "Canada", City: "Montreal", Hostname: "canada-montreal-ca-version-2.expressnetw.com"},
 		{Country: "Canada", City: "Toronto", Hostname: "canada-toronto-2-ca-version-2.expressnetw.com"},
 		{Country: "Canada", City: "Toronto", Hostname: "canada-toronto-ca-version-2.expressnetw.com"},
-		{Country: "Canada", City: "Vancouver", Hostname: "canada-vancouver-ca-version-2.expressnetw.com"},
+		{Country: "Cayman Islands", Hostname: "caymanislands-ca-version-2.expressnetw.com"},
 		{Country: "Chile", Hostname: "chile-ca-version-2.expressnetw.com"},
 		{Country: "Colombia", Hostname: "colombia-ca-version-2.expressnetw.com"},
-		{Country: "Costa Rica", City: "Costa Rica", Hostname: "costarica-ca-version-2.expressnetw.com"},
+		{Country: "Costa Rica", Hostname: "costarica-ca-version-2.expressnetw.com"},
 		{Country: "Croatia", Hostname: "croatia-ca-version-2.expressnetw.com"},
+		{Country: "Cuba", Hostname: "cuba-ca-version-2.expressnetw.com"},
 		{Country: "Cyprus", Hostname: "cyprus-ca-version-2.expressnetw.com"},
-		{Country: "Czech Republic", City: "Czech Republic", Hostname: "czechrepublic-ca-version-2.expressnetw.com"},
+		{Country: "Czech Republic", Hostname: "czechrepublic-ca-version-2.expressnetw.com"},
 		{Country: "Denmark", Hostname: "denmark-ca-version-2.expressnetw.com"},
+		{Country: "Dominican Republic", Hostname: "dominicanrepublic-ca-version-2.expressnetw.com"},
 		{Country: "Ecuador", Hostname: "ecuador-ca-version-2.expressnetw.com"},
 		{Country: "Egypt", Hostname: "egypt-ca-version-2.expressnetw.com"},
 		{Country: "Estonia", Hostname: "estonia-ca-version-2.expressnetw.com"},
 		{Country: "Finland", Hostname: "finland-ca-version-2.expressnetw.com"},
+		{Country: "France", City: "Alsace", Hostname: "france-alsace-ca-version-2.expressnetw.com"},
+		{Country: "France", City: "Marseille", Hostname: "france-marseille-ca-version-2.expressnetw.com"},
 		{Country: "France", City: "Paris", Hostname: "france-paris-1-ca-version-2.expressnetw.com"},
 		{Country: "France", City: "Paris", Hostname: "france-paris-2-ca-version-2.expressnetw.com"},
 		{Country: "France", City: "Strasbourg", Hostname: "france-strasbourg-ca-version-2.expressnetw.com"},
 		{Country: "Georgia", Hostname: "georgia-ca-version-2.expressnetw.com"},
-		{Country: "Germany", City: "Frankfurt", Hostname: "germany-frankfurt-1-ca-version-2.expressnetw.com"},
-		{Country: "Germany", City: "Frankfurt", Hostname: "germany-frankfurt-2-ca-version-2.expressnetw.com"},
 		{Country: "Germany", City: "Frankfurt", Hostname: "germany-darmstadt-ca-version-2.expressnetw.com"},
+		{Country: "Germany", City: "Frankfurt", Hostname: "germany-frankfurt-1-ca-version-2.expressnetw.com"},
 		{Country: "Germany", City: "Nuremberg", Hostname: "germany-nuremberg-ca-version-2.expressnetw.com"},
+		{Country: "Ghana", Hostname: "ghana-ca-version-2.expressnetw.com"},
 		{Country: "Greece", Hostname: "greece-ca-version-2.expressnetw.com"},
+		{Country: "Guam", Hostname: "guam-ca-version-2.expressnetw.com"},
 		{Country: "Guatemala", Hostname: "guatemala-ca-version-2.expressnetw.com"},
-		{Country: "Hong Kong", City: "Hong Kong", Hostname: "hongkong-2-ca-version-2.expressnetw.com"},
+		{Country: "Honduras", Hostname: "honduras-ca-version-2.expressnetw.com"},
-		{Country: "Hong Kong", City: "Hong Kong", Hostname: "hongkong4-ca-version-2.expressnetw.com"},
+		{Country: "Hong Kong", Hostname: "hongkong-1-ca-version-2.expressnetw.com"},
+		{Country: "Hong Kong", Hostname: "hongkong-2-ca-version-2.expressnetw.com"},
 		{Country: "Hungary", Hostname: "hungary-ca-version-2.expressnetw.com"},
 		{Country: "Iceland", Hostname: "iceland-ca-version-2.expressnetw.com"},
-		{Country: "India", City: "Chennai", Hostname: "india-chennai-ca-version-2.expressnetw.com"},
+		{Country: "India (via Singapore)", Hostname: "india-sg-ca-version-2.expressnetw.com"},
-		{Country: "India", City: "Mumbai", Hostname: "india-mumbai-1-ca-version-2.expressnetw.com"},
+		{Country: "India (via UK)", Hostname: "india-uk-ca-version-2.expressnetw.com"},
 		{Country: "Indonesia", Hostname: "indonesia-ca-version-2.expressnetw.com"},
 		{Country: "Ireland", Hostname: "ireland-ca-version-2.expressnetw.com"},
-		{Country: "Isle Of Man", City: "Isle Of Man", Hostname: "isleofman-ca-version-2.expressnetw.com"},
+		{Country: "Isle of Man", Hostname: "isleofman-ca-version-2.expressnetw.com"},
 		{Country: "Israel", Hostname: "israel-ca-version-2.expressnetw.com"},
 		{Country: "Italy", City: "Cosenza", Hostname: "italy-cosenza-ca-version-2.expressnetw.com"},
 		{Country: "Italy", City: "Milan", Hostname: "italy-milan-ca-version-2.expressnetw.com"},
-		{Country: "Japan", City: "Kawasaki", Hostname: "japan-kawasaki-ca-version-2.expressnetw.com"},
+		{Country: "Italy", City: "Naples", Hostname: "italy-naples-ca-version-2.expressnetw.com"},
-		{Country: "Japan", City: "Tokyo", Hostname: "japan-tokyo-1-ca-version-2.expressnetw.com"},
+		{Country: "Jamaica", Hostname: "jamaica-ca-version-2.expressnetw.com"},
-		{Country: "Japan", City: "Tokyo", Hostname: "japan-tokyo-2-ca-version-2.expressnetw.com"},
+		{Country: "Japan", City: "Osaka", Hostname: "japan-osaka-ca-version-2.expressnetw.com"},
+		{Country: "Japan", City: "Shibuya", Hostname: "japan-shibuya-ca-version-2.expressnetw.com"},
+		{Country: "Japan", City: "Tokyo", Hostname: "japan-tokyo-ca-version-2.expressnetw.com"},
+		{Country: "Japan", City: "Yokohama", Hostname: "japan-yokohama-ca-version-2.expressnetw.com"},
 		{Country: "Jersey", Hostname: "jersey-ca-version-2.expressnetw.com"},
 		{Country: "Kazakhstan", Hostname: "kazakhstan-ca-version-2.expressnetw.com"},
 		{Country: "Kenya", Hostname: "kenya-ca-version-2.expressnetw.com"},
-		{Country: "Kyrgyzstan", Hostname: "kyrgyzstan-ca-version-2.expressnetw.com"},
 		{Country: "Laos", Hostname: "laos-ca-version-2.expressnetw.com"},
 		{Country: "Latvia", Hostname: "latvia-ca-version-2.expressnetw.com"},
+		{Country: "Lebanon", Hostname: "lebanon-ca-version-2.expressnetw.com"},
 		{Country: "Liechtenstein", Hostname: "liechtenstein-ca-version-2.expressnetw.com"},
 		{Country: "Lithuania", Hostname: "lithuania-ca-version-2.expressnetw.com"},
 		{Country: "Luxembourg", Hostname: "luxembourg-ca-version-2.expressnetw.com"},
@@ -86,21 +99,22 @@ func hardcodedServers() (servers []models.Server) {
 		{Country: "Monaco", Hostname: "monaco-ca-version-2.expressnetw.com"},
 		{Country: "Mongolia", Hostname: "mongolia-ca-version-2.expressnetw.com"},
 		{Country: "Montenegro", Hostname: "montenegro-ca-version-2.expressnetw.com"},
+		{Country: "Morocco", Hostname: "morocco-ca-version-2.expressnetw.com"},
 		{Country: "Myanmar", Hostname: "myanmar-ca-version-2.expressnetw.com"},
 		{Country: "Nepal", Hostname: "nepal-ca-version-2.expressnetw.com"},
-		{Country: "Netherlands", City: "Amsterdam", Hostname: "netherlands-amsterdam-2-ca-version-2.expressnetw.com"},
 		{Country: "Netherlands", City: "Amsterdam", Hostname: "netherlands-amsterdam-ca-version-2.expressnetw.com"},
 		{Country: "Netherlands", City: "Rotterdam", Hostname: "netherlands-rotterdam-ca-version-2.expressnetw.com"},
 		{Country: "Netherlands", City: "The Hague", Hostname: "netherlands-thehague-ca-version-2.expressnetw.com"},
-		{Country: "New Zealand", City: "New Zealand", Hostname: "newzealand-ca-version-2.expressnetw.com"},
+		{Country: "New Zealand", Hostname: "newzealand-ca-version-2.expressnetw.com"},
-		{Country: "North Macedonia", City: "North Macedonia", Hostname: "macedonia-ca-version-2.expressnetw.com"},
+		{Country: "North Macedonia", Hostname: "macedonia-ca-version-2.expressnetw.com"},
 		{Country: "Norway", Hostname: "norway-ca-version-2.expressnetw.com"},
 		{Country: "Pakistan", Hostname: "pakistan-ca-version-2.expressnetw.com"},
 		{Country: "Panama", Hostname: "panama-ca-version-2.expressnetw.com"},
 		{Country: "Peru", Hostname: "peru-ca-version-2.expressnetw.com"},
-		{Country: "Philippines Via Singapore", City: "Philippines Via Singapore", Hostname: "ph-via-sing-ca-version-2.expressnetw.com"},
+		{Country: "Philippines (via Singapore)", Hostname: "ph-via-sing-ca-version-2.expressnetw.com"},
 		{Country: "Poland", Hostname: "poland-ca-version-2.expressnetw.com"},
 		{Country: "Portugal", Hostname: "portugal-ca-version-2.expressnetw.com"},
+		{Country: "Puerto Rico", Hostname: "puertorico-ca-version-2.expressnetw.com"},
 		{Country: "Romania", Hostname: "romania-ca-version-2.expressnetw.com"},
 		{Country: "Serbia", Hostname: "serbia-ca-version-2.expressnetw.com"},
 		{Country: "Singapore", City: "CBD", Hostname: "singapore-cbd-ca-version-2.expressnetw.com"},
@@ -108,43 +122,58 @@ func hardcodedServers() (servers []models.Server) {
 		{Country: "Singapore", City: "Marina Bay", Hostname: "singapore-marinabay-ca-version-2.expressnetw.com"},
 		{Country: "Slovakia", Hostname: "slovakia-ca-version-2.expressnetw.com"},
 		{Country: "Slovenia", Hostname: "slovenia-ca-version-2.expressnetw.com"},
-		{Country: "South Africa", City: "South Africa", Hostname: "southafrica-ca-version-2.expressnetw.com"},
+		{Country: "South Africa", Hostname: "southafrica-ca-version-2.expressnetw.com"},
-		{Country: "South Korea", City: "South Korea", Hostname: "southkorea2-ca-version-2.expressnetw.com"},
+		{Country: "South Korea", Hostname: "southkorea2-ca-version-2.expressnetw.com"},
 		{Country: "Spain", City: "Barcelona", Hostname: "spain-barcelona-ca-version-2.expressnetw.com"},
+		{Country: "Spain", City: "Barcelona", Hostname: "spain-barcelona2-ca-version-2.expressnetw.com"},
 		{Country: "Spain", City: "Madrid", Hostname: "spain-ca-version-2.expressnetw.com"},
-		{Country: "Sri Lanka", City: "Sri Lanka", Hostname: "srilanka-ca-version-2.expressnetw.com"},
+		{Country: "Sri Lanka", Hostname: "srilanka-ca-version-2.expressnetw.com"},
 		{Country: "Sweden", Hostname: "sweden-ca-version-2.expressnetw.com"},
+		{Country: "Sweden", Hostname: "sweden2-ca-version-2.expressnetw.com"},
 		{Country: "Switzerland", Hostname: "switzerland-2-ca-version-2.expressnetw.com"},
 		{Country: "Switzerland", Hostname: "switzerland-ca-version-2.expressnetw.com"},
-		{Country: "Taiwan", Hostname: "taiwan-2-ca-version-2.expressnetw.com"},
+		{Country: "Taiwan", Hostname: "taiwan-3-ca-version-2.expressnetw.com"},
 		{Country: "Thailand", Hostname: "thailand-ca-version-2.expressnetw.com"},
+		{Country: "Trinidad and Tobago", Hostname: "trinidadandtobago-ca-version-2.expressnetw.com"},
 		{Country: "Turkey", Hostname: "turkey-ca-version-2.expressnetw.com"},
-		{Country: "Ukraine", Hostname: "ukraine-ca-version-2.expressnetw.com"},
+		{Country: "UK", City: "Docklands", Hostname: "uk-1-docklands-ca-version-2.expressnetw.com"},
-		{Country: "UK", City: "Docklands", Hostname: "uk-berkshire-2-ca-version-2.expressnetw.com"},
+		{Country: "UK", City: "East London", Hostname: "uk-east-london-ca-version-2.expressnetw.com"},
-		{Country: "UK", City: "London", Hostname: "uk-east-london-ca-version-2.expressnetw.com"},
 		{Country: "UK", City: "London", Hostname: "uk-london-ca-version-2.expressnetw.com"},
+		{Country: "UK", City: "Midlands", Hostname: "uk-midlands-ca-version-2.expressnetw.com"},
+		{Country: "UK", City: "Tottenham", Hostname: "uk-tottenham-ca-version-2.expressnetw.com"},
+		{Country: "UK", City: "Wembley", Hostname: "uk-wembley-ca-version-2.expressnetw.com"},
+		{Country: "Ukraine", Hostname: "ukraine-ca-version-2.expressnetw.com"},
 		{Country: "Uruguay", Hostname: "uruguay-ca-version-2.expressnetw.com"},
+		{Country: "USA", City: "Albuquerque", Hostname: "usa-albuquerque-ca-version-2.expressnetw.com"},
 		{Country: "USA", City: "Atlanta", Hostname: "usa-atlanta-ca-version-2.expressnetw.com"},
+		{Country: "USA", City: "Boston", Hostname: "us-boston-ca-version-2.expressnetw.com"},
 		{Country: "USA", City: "Chicago", Hostname: "usa-chicago-ca-version-2.expressnetw.com"},
-		{Country: "USA", City: "Dallas", Hostname: "usa-dallas-2-ca-version-2.expressnetw.com"},
 		{Country: "USA", City: "Dallas", Hostname: "usa-dallas-ca-version-2.expressnetw.com"},
 		{Country: "USA", City: "Denver", Hostname: "usa-denver-ca-version-2.expressnetw.com"},
-		{Country: "USA", City: "Los Angeles", Hostname: "usa-losangeles-1-ca-version-2.expressnetw.com"},
+		{Country: "USA", City: "Houston", Hostname: "usa-houston-ca-version-2.expressnetw.com"},
+		{Country: "USA", City: "Jackson", Hostname: "us-jackson-ca-version-2.expressnetw.com"},
+		{Country: "USA", City: "Lincoln Park", Hostname: "usa-lincolnpark-ca-version-2.expressnetw.com"},
+		{Country: "USA", City: "Little Rock", Hostname: "us-littlerock-ca-version-2.expressnetw.com"},
 		{Country: "USA", City: "Los Angeles", Hostname: "usa-losangeles-2-ca-version-2.expressnetw.com"},
 		{Country: "USA", City: "Los Angeles", Hostname: "usa-losangeles-3-ca-version-2.expressnetw.com"},
-		{Country: "USA", City: "Los Angeles", Hostname: "usa-losangeles5-ca-version-2.expressnetw.com"},
 		{Country: "USA", City: "Los Angeles", Hostname: "usa-losangeles-ca-version-2.expressnetw.com"},
+		{Country: "USA", City: "Los Angeles", Hostname: "usa-losangeles5-ca-version-2.expressnetw.com"},
+		{Country: "USA", City: "Miami", Hostname: "usa-miami-2-ca-version-2.expressnetw.com"},
 		{Country: "USA", City: "Miami", Hostname: "usa-miami-ca-version-2.expressnetw.com"},
 		{Country: "USA", City: "New Jersey", Hostname: "usa-newjersey-1-ca-version-2.expressnetw.com"},
-		{Country: "USA", City: "New Jersey", Hostname: "usa-newjersey2-ca-version-2.expressnetw.com"},
 		{Country: "USA", City: "New Jersey", Hostname: "usa-newjersey-3-ca-version-2.expressnetw.com"},
-		{Country: "USA", City: "New York", Hostname: "us-new-york-2-ca-version-2.expressnetw.com"},
+		{Country: "USA", City: "New Jersey", Hostname: "usa-newjersey2-ca-version-2.expressnetw.com"},
+		{Country: "USA", City: "New Orleans", Hostname: "us-neworleans-ca-version-2.expressnetw.com"},
 		{Country: "USA", City: "New York", Hostname: "usa-newyork-ca-version-2.expressnetw.com"},
+		{Country: "USA", City: "Oklahoma City", Hostname: "us-oklahoma-ca-version-2.expressnetw.com"},
+		{Country: "USA", City: "Phoenix", Hostname: "usa-phoenix-ca-version-2.expressnetw.com"},
 		{Country: "USA", City: "Salt Lake City", Hostname: "usa-saltlakecity-ca-version-2.expressnetw.com"},
 		{Country: "USA", City: "San Francisco", Hostname: "usa-sanfrancisco-ca-version-2.expressnetw.com"},
+		{Country: "USA", City: "Santa Monica", Hostname: "usa-santa-monica-ca-version-2.expressnetw.com"},
 		{Country: "USA", City: "Seattle", Hostname: "usa-seattle-ca-version-2.expressnetw.com"},
 		{Country: "USA", City: "Tampa", Hostname: "usa-tampa-1-ca-version-2.expressnetw.com"},
 		{Country: "USA", City: "Washington DC", Hostname: "usa-washingtondc-ca-version-2.expressnetw.com"},
+		{Country: "USA", City: "Wichita", Hostname: "us-wichita-ca-version-2.expressnetw.com"},
 		{Country: "Uzbekistan", Hostname: "uzbekistan-ca-version-2.expressnetw.com"},
 		{Country: "Venezuela", Hostname: "venezuela-ca-version-2.expressnetw.com"},
 		{Country: "Vietnam", Hostname: "vietnam-ca-version-2.expressnetw.com"},

internal/provider/privateinternetaccess/portforward.go

@@ -407,7 +407,7 @@ func bindPort(ctx context.Context, client *http.Client, apiIPAddress netip.Addr,
 // replaceInErr is used to remove sensitive information from errors.
 func replaceInErr(err error, substitutions map[string]string) error {
 	s := replaceInString(err.Error(), substitutions)
-	return errors.New(s) //nolint:goerr113
+	return errors.New(s) //nolint:err113
 }
 
 // replaceInString is used to remove sensitive information.

internal/provider/providers.go

@@ -62,7 +62,7 @@ func NewProviders(storage Storage, timeNow func() time.Time,
 	providerNameToProvider := map[string]Provider{
 		providers.Airvpn:                airvpn.New(storage, randSource, client),
 		providers.Custom:                custom.New(extractor),
-		providers.Cyberghost:            cyberghost.New(storage, randSource, parallelResolver),
+		providers.Cyberghost:            cyberghost.New(storage, randSource, updaterWarner, parallelResolver),
 		providers.Expressvpn:            expressvpn.New(storage, randSource, unzipper, updaterWarner, parallelResolver),
 		providers.Fastestvpn:            fastestvpn.New(storage, randSource, client, updaterWarner, parallelResolver),
 		providers.Giganews:              giganews.New(storage, randSource, unzipper, updaterWarner, parallelResolver),

internal/provider/vpnunlimited/openvpnconf.go

@@ -20,8 +20,8 @@ func (p *Provider) OpenVPNConfig(connection models.Connection,
 		Ciphers:       []string{openvpn.AES256cbc},
 		Auth:          openvpn.SHA512,
 		CAs: []string{
-			"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",             //nolint:lll
+			"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",         //nolint:lll
-			"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", //nolint:lll
+			"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", //nolint:lll
 		},
 		ExtraLines: []string{
 			"route-metric 1",

internal/publicip/api/multi.go

@@ -36,7 +36,7 @@ func FetchMultiInfo(ctx context.Context, fetcher InfoFetcher, ips []netip.Addr)
 	}
 
 	results = make([]models.PublicIP, len(ips))
-	for range len(ips) {
+	for range ips {
 		aResult := <-resultsCh
 		if aResult.err != nil {
 			if err == nil {

internal/publicip/loop.go

@@ -114,6 +114,11 @@ func (l *Loop) run(runCtx context.Context, runDone chan<- struct{},
 			continue
 		}
 
+		if !*l.settings.Enabled {
+			singleRunResult <- nil
+			continue
+		}
+
 		result, err := l.fetcher.FetchInfo(singleRunCtx, netip.Addr{})
 		if err != nil {
 			err = fmt.Errorf("fetching information: %w", err)

internal/server/dns.go

@@ -26,7 +26,7 @@ type dnsHandler struct {
 func (h *dnsHandler) ServeHTTP(w http.ResponseWriter, r *http.Request) {
 	r.RequestURI = strings.TrimPrefix(r.RequestURI, "/dns")
 	switch r.RequestURI {
-	case "/status": //nolint:goconst
+	case "/status":
 		switch r.Method {
 		case http.MethodGet:
 			h.getStatus(w)

internal/server/logger.go

@@ -15,6 +15,7 @@ type infoWarner interface {
 
 type infoer interface {
 	Info(s string)
+	Infof(format string, args ...any)
 }
 
 type warner interface {

internal/server/middlewares/auth/configfile.go

@@ -13,9 +13,6 @@ import (
 func Read(filepath string) (settings Settings, err error) {
 	file, err := os.Open(filepath)
 	if err != nil {
-		if errors.Is(err, os.ErrNotExist) {
-			return Settings{}, nil
-		}
 		return settings, fmt.Errorf("opening file: %w", err)
 	}
 	decoder := toml.NewDecoder(file)

internal/server/server.go

@@ -2,7 +2,9 @@ package server
 
 import (
 	"context"
+	"errors"
 	"fmt"
+	"os"
 
 	"github.com/qdm12/gluetun/internal/httpserver"
 	"github.com/qdm12/gluetun/internal/models"
@@ -17,8 +19,12 @@ func New(ctx context.Context, address string, logEnabled bool, logger Logger,
 	server *httpserver.Server, err error,
 ) {
 	authSettings, err := auth.Read(authConfigPath)
-	if err != nil {
+	switch {
+	case errors.Is(err, os.ErrNotExist): // no auth file present
+	case err != nil:
 		return nil, fmt.Errorf("reading auth settings: %w", err)
+	default:
+		logger.Infof("read %d roles from authentication file", len(authSettings.Roles))
 	}
 	authSettings.SetDefaults()
 	err = authSettings.Validate()

internal/vpn/interfaces.go

@@ -99,3 +99,13 @@ type CmdStarter interface {
 		stdoutLines, stderrLines <-chan string,
 		waitError <-chan error, startErr error)
 }
+
+type HealthChecker interface {
+	SetConfig(tlsDialAddr string, icmpTarget netip.Addr)
+	Start(ctx context.Context) (runError <-chan error, err error)
+	Stop() error
+}
+
+type HealthServer interface {
+	SetError(err error)
+}

internal/vpn/loop.go

@@ -8,20 +8,24 @@ import (
 	"github.com/qdm12/gluetun/internal/constants"
 	"github.com/qdm12/gluetun/internal/loopstate"
 	"github.com/qdm12/gluetun/internal/models"
+	"github.com/qdm12/gluetun/internal/netlink"
 	"github.com/qdm12/gluetun/internal/vpn/state"
 	"github.com/qdm12/log"
 )
 
 type Loop struct {
-	statusManager *loopstate.State
+	statusManager  *loopstate.State
-	state         *state.State
+	state          *state.State
-	providers     Providers
+	providers      Providers
-	storage       Storage
+	storage        Storage
+	healthSettings settings.Health
+	healthChecker  HealthChecker
+	healthServer   HealthServer
 	// Fixed parameters
-	buildInfo     models.BuildInformation
+	buildInfo        models.BuildInformation
-	versionInfo   bool
+	versionInfo      bool
-	ipv6Supported bool
+	ipv6SupportLevel netlink.IPv6SupportLevel
-	vpnInputPorts []uint16 // TODO make changeable through stateful firewall
+	vpnInputPorts    []uint16 // TODO make changeable through stateful firewall
 	// Configurators
 	openvpnConf OpenVPN
 	netLinker   NetLinker
@@ -48,8 +52,9 @@ const (
 	defaultBackoffTime = 15 * time.Second
 )
 
-func NewLoop(vpnSettings settings.VPN, ipv6Supported bool, vpnInputPorts []uint16,
+func NewLoop(vpnSettings settings.VPN, ipv6SupportLevel netlink.IPv6SupportLevel, vpnInputPorts []uint16,
-	providers Providers, storage Storage, openvpnConf OpenVPN,
+	providers Providers, storage Storage, healthSettings settings.Health,
+	healthChecker HealthChecker, healthServer HealthServer, openvpnConf OpenVPN,
 	netLinker NetLinker, fw Firewall, routing Routing,
 	portForward PortForward, starter CmdStarter,
 	publicip PublicIPLoop, dnsLooper DNSLoop,
@@ -65,29 +70,32 @@ func NewLoop(vpnSettings settings.VPN, ipv6Supported bool, vpnInputPorts []uint1
 	state := state.New(statusManager, vpnSettings)
 
 	return &Loop{
-		statusManager: statusManager,
+		statusManager:    statusManager,
-		state:         state,
+		state:            state,
-		providers:     providers,
+		providers:        providers,
-		storage:       storage,
+		storage:          storage,
-		buildInfo:     buildInfo,
+		healthSettings:   healthSettings,
-		versionInfo:   versionInfo,
+		healthChecker:    healthChecker,
-		ipv6Supported: ipv6Supported,
+		healthServer:     healthServer,
-		vpnInputPorts: vpnInputPorts,
+		buildInfo:        buildInfo,
-		openvpnConf:   openvpnConf,
+		versionInfo:      versionInfo,
-		netLinker:     netLinker,
+		ipv6SupportLevel: ipv6SupportLevel,
-		fw:            fw,
+		vpnInputPorts:    vpnInputPorts,
-		routing:       routing,
+		openvpnConf:      openvpnConf,
-		portForward:   portForward,
+		netLinker:        netLinker,
-		publicip:      publicip,
+		fw:               fw,
-		dnsLooper:     dnsLooper,
+		routing:          routing,
-		starter:       starter,
+		portForward:      portForward,
-		logger:        logger,
+		publicip:         publicip,
-		client:        client,
+		dnsLooper:        dnsLooper,
-		start:         start,
+		starter:          starter,
-		running:       running,
+		logger:           logger,
-		stop:          stop,
+		client:           client,
-		stopped:       stopped,
+		start:            start,
-		userTrigger:   true,
+		running:          running,
-		backoffTime:   defaultBackoffTime,
+		stop:             stop,
+		stopped:          stopped,
+		userTrigger:      true,
+		backoffTime:      defaultBackoffTime,
 	}
 }

internal/vpn/openvpn.go

@@ -5,6 +5,8 @@ import (
 	"fmt"
 
 	"github.com/qdm12/gluetun/internal/configuration/settings"
+	"github.com/qdm12/gluetun/internal/models"
+	"github.com/qdm12/gluetun/internal/netlink"
 	"github.com/qdm12/gluetun/internal/openvpn"
 	"github.com/qdm12/gluetun/internal/provider"
 )
@@ -13,40 +15,40 @@ import (
 // It returns a serverName for port forwarding (PIA) and an error if it fails.
 func setupOpenVPN(ctx context.Context, fw Firewall,
 	openvpnConf OpenVPN, providerConf provider.Provider,
-	settings settings.VPN, ipv6Supported bool, starter CmdStarter,
+	settings settings.VPN, ipv6SupportLevel netlink.IPv6SupportLevel, starter CmdStarter,
-	logger openvpn.Logger) (runner *openvpn.Runner, serverName string,
+	logger openvpn.Logger) (runner *openvpn.Runner, connection models.Connection, err error,
-	canPortForward bool, err error,
 ) {
-	connection, err := providerConf.GetConnection(settings.Provider.ServerSelection, ipv6Supported)
+	ipv6Internet := ipv6SupportLevel == netlink.IPv6Internet
+	connection, err = providerConf.GetConnection(settings.Provider.ServerSelection, ipv6Internet)
 	if err != nil {
-		return nil, "", false, fmt.Errorf("finding a valid server connection: %w", err)
+		return nil, models.Connection{}, fmt.Errorf("finding a valid server connection: %w", err)
 	}
 
-	lines := providerConf.OpenVPNConfig(connection, settings.OpenVPN, ipv6Supported)
+	lines := providerConf.OpenVPNConfig(connection, settings.OpenVPN, ipv6SupportLevel.IsSupported())
 
 	if err := openvpnConf.WriteConfig(lines); err != nil {
-		return nil, "", false, fmt.Errorf("writing configuration to file: %w", err)
+		return nil, models.Connection{}, fmt.Errorf("writing configuration to file: %w", err)
 	}
 
 	if *settings.OpenVPN.User != "" {
 		err := openvpnConf.WriteAuthFile(*settings.OpenVPN.User, *settings.OpenVPN.Password)
 		if err != nil {
-			return nil, "", false, fmt.Errorf("writing auth to file: %w", err)
+			return nil, models.Connection{}, fmt.Errorf("writing auth to file: %w", err)
 		}
 	}
 
 	if *settings.OpenVPN.KeyPassphrase != "" {
 		err := openvpnConf.WriteAskPassFile(*settings.OpenVPN.KeyPassphrase)
 		if err != nil {
-			return nil, "", false, fmt.Errorf("writing askpass file: %w", err)
+			return nil, models.Connection{}, fmt.Errorf("writing askpass file: %w", err)
 		}
 	}
 
 	if err := fw.SetVPNConnection(ctx, connection, settings.OpenVPN.Interface); err != nil {
-		return nil, "", false, fmt.Errorf("allowing VPN connection through firewall: %w", err)
+		return nil, models.Connection{}, fmt.Errorf("allowing VPN connection through firewall: %w", err)
 	}
 
 	runner = openvpn.NewRunner(settings.OpenVPN, starter, logger)
 
-	return runner, connection.ServerName, connection.PortForward, nil
+	return runner, connection, nil
 }

internal/vpn/run.go

@@ -5,6 +5,7 @@ import (
 
 	"github.com/qdm12/gluetun/internal/constants"
 	"github.com/qdm12/gluetun/internal/constants/vpn"
+	"github.com/qdm12/gluetun/internal/models"
 	"github.com/qdm12/log"
 )
 
@@ -28,40 +29,41 @@ func (l *Loop) Run(ctx context.Context, done chan<- struct{}) {
 		var vpnRunner interface {
 			Run(ctx context.Context, waitError chan<- error, tunnelReady chan<- struct{})
 		}
-		var serverName, vpnInterface string
+		var vpnInterface string
-		var canPortForward bool
+		var connection models.Connection
 		var err error
 		subLogger := l.logger.New(log.SetComponent(settings.Type))
 		if settings.Type == vpn.OpenVPN {
 			vpnInterface = settings.OpenVPN.Interface
-			vpnRunner, serverName, canPortForward, err = setupOpenVPN(ctx, l.fw,
+			vpnRunner, connection, err = setupOpenVPN(ctx, l.fw,
-				l.openvpnConf, providerConf, settings, l.ipv6Supported, l.starter, subLogger)
+				l.openvpnConf, providerConf, settings, l.ipv6SupportLevel, l.starter, subLogger)
 		} else { // Wireguard
 			vpnInterface = settings.Wireguard.Interface
-			vpnRunner, serverName, canPortForward, err = setupWireguard(ctx, l.netLinker, l.fw,
+			vpnRunner, connection, err = setupWireguard(ctx, l.netLinker, l.fw,
-				providerConf, settings, l.ipv6Supported, subLogger)
+				providerConf, settings, l.ipv6SupportLevel, subLogger)
 		}
 		if err != nil {
 			l.crashed(ctx, err)
 			continue
 		}
 		tunnelUpData := tunnelUpData{
-			serverName:     serverName,
+			serverIP:       connection.IP,
-			canPortForward: canPortForward,
+			serverName:     connection.ServerName,
+			canPortForward: connection.PortForward,
 			portForwarder:  portForwarder,
 			vpnIntf:        vpnInterface,
 			username:       settings.Provider.PortForwarding.Username,
 			password:       settings.Provider.PortForwarding.Password,
 		}
 
-		openvpnCtx, openvpnCancel := context.WithCancel(context.Background())
+		vpnCtx, vpnCancel := context.WithCancel(context.Background())
 		waitError := make(chan error)
 		tunnelReady := make(chan struct{})
 
-		go vpnRunner.Run(openvpnCtx, waitError, tunnelReady)
+		go vpnRunner.Run(vpnCtx, waitError, tunnelReady)
 
 		if err := l.waitForError(ctx, waitError); err != nil {
-			openvpnCancel()
+			vpnCancel()
 			l.crashed(ctx, err)
 			continue
 		}
@@ -73,10 +75,10 @@ func (l *Loop) Run(ctx context.Context, done chan<- struct{}) {
 		for stayHere {
 			select {
 			case <-tunnelReady:
-				go l.onTunnelUp(openvpnCtx, tunnelUpData)
+				go l.onTunnelUp(vpnCtx, ctx, tunnelUpData)
 			case <-ctx.Done():
 				l.cleanup()
-				openvpnCancel()
+				vpnCancel()
 				<-waitError
 				close(waitError)
 				return
@@ -84,7 +86,7 @@ func (l *Loop) Run(ctx context.Context, done chan<- struct{}) {
 				l.userTrigger = true
 				l.logger.Info("stopping")
 				l.cleanup()
-				openvpnCancel()
+				vpnCancel()
 				<-waitError
 				// do not close waitError or the waitError
 				// select case will trigger
@@ -97,7 +99,7 @@ func (l *Loop) Run(ctx context.Context, done chan<- struct{}) {
 				l.statusManager.Lock() // prevent SetStatus from running in parallel
 
 				l.cleanup()
-				openvpnCancel()
+				vpnCancel()
 				l.statusManager.SetStatus(constants.Crashed)
 				l.logAndWait(ctx, err)
 				stayHere = false
@@ -105,6 +107,6 @@ func (l *Loop) Run(ctx context.Context, done chan<- struct{}) {
 				l.statusManager.Unlock()
 			}
 		}
-		openvpnCancel()
+		vpnCancel()
 	}
 }

internal/vpn/tunnelup.go

@@ -2,6 +2,7 @@ package vpn
 
 import (
 	"context"
+	"net/netip"
 
 	"github.com/qdm12/dns/v2/pkg/check"
 	"github.com/qdm12/gluetun/internal/constants"
@@ -9,6 +10,8 @@ import (
 )
 
 type tunnelUpData struct {
+	// Healthcheck
+	serverIP netip.Addr
 	// Port forwarding
 	vpnIntf        string
 	serverName     string // used for PIA
@@ -18,7 +21,7 @@ type tunnelUpData struct {
 	portForwarder  PortForwarder
 }
 
-func (l *Loop) onTunnelUp(ctx context.Context, data tunnelUpData) {
+func (l *Loop) onTunnelUp(ctx, loopCtx context.Context, data tunnelUpData) {
 	l.client.CloseIdleConnections()
 
 	for _, vpnPort := range l.vpnInputPorts {
@@ -28,7 +31,22 @@ func (l *Loop) onTunnelUp(ctx context.Context, data tunnelUpData) {
 		}
 	}
 
-	if *l.dnsLooper.GetSettings().DoT.Enabled {
+	icmpTarget := l.healthSettings.ICMPTargetIP
+	if icmpTarget.IsUnspecified() {
+		icmpTarget = data.serverIP
+	}
+	l.healthChecker.SetConfig(l.healthSettings.TargetAddress, icmpTarget)
+
+	healthErrCh, err := l.healthChecker.Start(ctx)
+	l.healthServer.SetError(err)
+	if err != nil {
+		// Note this restart call must be done in a separate goroutine
+		// from the VPN loop goroutine.
+		l.restartVPN(loopCtx, err)
+		return
+	}
+
+	if *l.dnsLooper.GetSettings().ServerEnabled {
 		_, _ = l.dnsLooper.ApplyStatus(ctx, constants.Running)
 	} else {
 		err := check.WaitForDNS(ctx, check.Settings{})
@@ -37,7 +55,7 @@ func (l *Loop) onTunnelUp(ctx context.Context, data tunnelUpData) {
 		}
 	}
 
-	err := l.publicip.RunOnce(ctx)
+	err = l.publicip.RunOnce(ctx)
 	if err != nil {
 		l.logger.Error("getting public IP address information: " + err.Error())
 	}
@@ -56,4 +74,41 @@ func (l *Loop) onTunnelUp(ctx context.Context, data tunnelUpData) {
 	if err != nil {
 		l.logger.Error(err.Error())
 	}
+
+	l.collectHealthErrors(ctx, loopCtx, healthErrCh)
+}
+
+func (l *Loop) collectHealthErrors(ctx, loopCtx context.Context, healthErrCh <-chan error) {
+	var previousHealthErr error
+	for {
+		select {
+		case <-ctx.Done():
+			_ = l.healthChecker.Stop()
+			return
+		case healthErr := <-healthErrCh:
+			l.healthServer.SetError(healthErr)
+			if healthErr != nil {
+				if *l.healthSettings.RestartVPN {
+					// Note this restart call must be done in a separate goroutine
+					// from the VPN loop goroutine.
+					_ = l.healthChecker.Stop()
+					l.restartVPN(loopCtx, healthErr)
+					return
+				}
+				l.logger.Warnf("healthcheck failed: %s", healthErr)
+				l.logger.Info("👉 See https://github.com/qdm12/gluetun-wiki/blob/main/faq/healthcheck.md")
+			} else if previousHealthErr != nil {
+				l.logger.Info("healthcheck passed successfully after previous failure(s)")
+			}
+			previousHealthErr = healthErr
+		}
+	}
+}
+
+func (l *Loop) restartVPN(ctx context.Context, healthErr error) {
+	l.logger.Warnf("restarting VPN because it failed to pass the healthcheck: %s", healthErr)
+	l.logger.Info("👉 See https://github.com/qdm12/gluetun-wiki/blob/main/faq/healthcheck.md")
+	l.logger.Info("DO NOT OPEN AN ISSUE UNLESS YOU HAVE READ AND TRIED EVERY POSSIBLE SOLUTION")
+	_, _ = l.ApplyStatus(ctx, constants.Stopped)
+	_, _ = l.ApplyStatus(ctx, constants.Running)
 }

internal/vpn/wireguard.go

@@ -5,6 +5,8 @@ import (
 	"fmt"
 
 	"github.com/qdm12/gluetun/internal/configuration/settings"
+	"github.com/qdm12/gluetun/internal/models"
+	"github.com/qdm12/gluetun/internal/netlink"
 	"github.com/qdm12/gluetun/internal/provider"
 	"github.com/qdm12/gluetun/internal/provider/utils"
 	"github.com/qdm12/gluetun/internal/wireguard"
@@ -15,15 +17,16 @@ import (
 // It returns a serverName for port forwarding (PIA) and an error if it fails.
 func setupWireguard(ctx context.Context, netlinker NetLinker,
 	fw Firewall, providerConf provider.Provider,
-	settings settings.VPN, ipv6Supported bool, logger wireguard.Logger) (
+	settings settings.VPN, ipv6SupportLevel netlink.IPv6SupportLevel, logger wireguard.Logger) (
-	wireguarder *wireguard.Wireguard, serverName string, canPortForward bool, err error,
+	wireguarder *wireguard.Wireguard, connection models.Connection, err error,
 ) {
-	connection, err := providerConf.GetConnection(settings.Provider.ServerSelection, ipv6Supported)
+	ipv6Internet := ipv6SupportLevel == netlink.IPv6Internet
+	connection, err = providerConf.GetConnection(settings.Provider.ServerSelection, ipv6Internet)
 	if err != nil {
-		return nil, "", false, fmt.Errorf("finding a VPN server: %w", err)
+		return nil, models.Connection{}, fmt.Errorf("finding a VPN server: %w", err)
 	}
 
-	wireguardSettings := utils.BuildWireguardSettings(connection, settings.Wireguard, ipv6Supported)
+	wireguardSettings := utils.BuildWireguardSettings(connection, settings.Wireguard, ipv6SupportLevel.IsSupported())
 
 	logger.Debug("Wireguard server public key: " + wireguardSettings.PublicKey)
 	logger.Debug("Wireguard client private key: " + gosettings.ObfuscateKey(wireguardSettings.PrivateKey))
@@ -31,13 +34,13 @@ func setupWireguard(ctx context.Context, netlinker NetLinker,
 
 	wireguarder, err = wireguard.New(wireguardSettings, netlinker, logger)
 	if err != nil {
-		return nil, "", false, fmt.Errorf("creating Wireguard: %w", err)
+		return nil, models.Connection{}, fmt.Errorf("creating Wireguard: %w", err)
 	}
 
 	err = fw.SetVPNConnection(ctx, connection, settings.Wireguard.Interface)
 	if err != nil {
-		return nil, "", false, fmt.Errorf("setting firewall: %w", err)
+		return nil, models.Connection{}, fmt.Errorf("setting firewall: %w", err)
 	}
 
-	return wireguarder, connection.ServerName, connection.PortForward, nil
+	return wireguarder, connection, nil
 }

internal/wireguard/route.go

@@ -32,9 +32,14 @@ func (w *Wireguard) addRoutes(link netlink.Link, destinations []netip.Prefix,
 func (w *Wireguard) addRoute(link netlink.Link, dst netip.Prefix,
 	firewallMark uint32,
 ) (err error) {
+	family := netlink.FamilyV4
+	if dst.Addr().Is6() {
+		family = netlink.FamilyV6
+	}
 	route := netlink.Route{
 		LinkIndex: link.Index,
 		Dst:       dst,
+		Family:    family,
 		Table:     int(firewallMark),
 	}
 

internal/wireguard/route_test.go

@@ -37,6 +37,7 @@ func Test_Wireguard_addRoute(t *testing.T) {
 			expectedRoute: netlink.Route{
 				LinkIndex: linkIndex,
 				Dst:       ipPrefix,
+				Family:    netlink.FamilyV4,
 				Table:     firewallMark,
 			},
 		},
@@ -49,6 +50,7 @@ func Test_Wireguard_addRoute(t *testing.T) {
 			expectedRoute: netlink.Route{
 				LinkIndex: linkIndex,
 				Dst:       ipPrefix,
+				Family:    netlink.FamilyV4,
 				Table:     firewallMark,
 			},
 			routeAddErr: errDummy,

maintenance.md

@@ -1,6 +1,5 @@
 # Maintenance
 
-- Rename `UNBLOCK` to `DNS_HOSTNAMES_UNBLOCKED`
 - Change `Run` methods to `Start`+`Stop`, returning channels rather than injecting them
 - Go 1.18
   - gofumpt