Chore(deps): Bump golang.org/x/crypto from 0.44.0 to 0.45.0

Bumps [golang.org/x/crypto](https://github.com/golang/crypto) from 0.44.0 to 0.45.0.
- [Commits](https://github.com/golang/crypto/compare/v0.44.0...v0.45.0)

---
updated-dependencies:
- dependency-name: golang.org/x/crypto
  dependency-version: 0.45.0
  dependency-type: indirect
...

Signed-off-by: dependabot[bot] <support@github.com>

.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
-- Publicly accessible URL to a structured (JSON etc.) list of servers **and attach** an example Openvpn configuration file for both TCP and UDP
+- There is no need to support both OpenVPN and Wireguard for a provider, but it's better to support both if possible
+- 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:
@@ -59,13 +59,43 @@ jobs:
       - name: Run tests in test container
         run: |
           touch coverage.txt
-          docker run --rm \
+          docker run --rm --device /dev/net/tun \
           -v "$(pwd)/coverage.txt:/tmp/gobuild/coverage.txt" \
           test-container
 
       - 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
+
+      - name: Run Gluetun container with ProtonVPN configuration
+        run: echo -e "${{ secrets.PROTONVPN_WIREGUARD_PRIVATE_KEY }}" | ./ci/runner protonvpn
+
   codeql:
     runs-on: ubuntu-latest
     permissions:
@@ -73,15 +103,15 @@ jobs:
       contents: read
       security-events: write
     steps:
-      - uses: actions/checkout@v4
-      - uses: actions/setup-go@v5
+      - uses: actions/checkout@v5
+      - uses: actions/setup-go@v6
         with:
-          go-version: "^1.23"
-      - uses: github/codeql-action/init@v3
+          go-version-file: go.mod
+      - uses: github/codeql-action/init@v4
         with:
           languages: go
-      - uses: github/codeql-action/autobuild@v3
-      - uses: github/codeql-action/analyze@v3
+      - uses: github/codeql-action/autobuild@v4
+      - uses: github/codeql-action/analyze@v4
 
   publish:
     if: |
@@ -91,14 +121,14 @@ jobs:
         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, codeql]
+    needs: [verify, verify-private, codeql]
     permissions:
       actions: read
       contents: read
       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@v16
+      - uses: DavidAnson/markdownlint-cli2-action@v21
         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 +1,73 @@
-linters-settings:
-  misspell:
-    locale: US
+version: "2"
 
-issues:
-  exclude-rules:
-    - path: _test\.go
-      linters:
-        - dupl
-        - err113
-        - containedctx
-        - maintidx
-    - path: "internal\\/server\\/.+\\.go"
-      linters:
-        - dupl
-    - 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
+formatters:
+  enable:
+    - gci
+    - gofumpt
+    - goimports
+  exclusions:
+    generated: lax
+    paths:
+      - third_party$
+      - builtin$
+      - examples$
 
 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:
+          - lll
+        source: "^// https://.+$"
+      - linters:
+          - err113
+          - mnd
+        path: ci\/.+\.go
+
+    paths:
+      - third_party$
+      - builtin$
+      - examples$
   enable:
     # - cyclop
     # - errorlint
@@ -42,7 +88,6 @@ linters:
     - exhaustive
     - fatcontext
     - forcetypeassert
-    - gci
     - gocheckcompilerdirectives
     - gochecknoglobals
     - gochecknoinits
@@ -51,9 +96,7 @@ linters:
     - gocritic
     - gocyclo
     - godot
-    - gofumpt
     - goheader
-    - goimports
     - gomoddirectives
     - goprintffuncname
     - gosec
@@ -86,7 +129,6 @@ 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 GO_ALPINE_VERSION=3.20
-ARG GO_VERSION=1.23
-ARG XCPUTRANSLATE_VERSION=v0.6.0
-ARG GOLANGCI_LINT_VERSION=v1.61.0
+ARG ALPINE_VERSION=3.22
+ARG GO_ALPINE_VERSION=3.22
+ARG GO_VERSION=1.25
+ARG XCPUTRANSLATE_VERSION=v0.9.0
+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=${BUILDPLATFORM} qmcgaw/binpot:golangci-lint-${GOLANGCI_LINT_VERSION} AS golangci-lint
-FROM --platform=${BUILDPLATFORM} qmcgaw/binpot:mockgen-${MOCKGEN_VERSION} AS mockgen
+FROM --platform=${BUILDPLATFORM} ghcr.io/qdm12/xcputranslate:${XCPUTRANSLATE_VERSION} AS xcputranslate
+FROM --platform=${BUILDPLATFORM} ghcr.io/qdm12/binpot:golangci-lint-${GOLANGCI_LINT_VERSION} AS golangci-lint
+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 && \
@@ -125,6 +125,8 @@ ENV VPN_SERVICE_PROVIDER=pia \
     VPN_PORT_FORWARDING_STATUS_FILE="/tmp/gluetun/forwarded_port" \
     VPN_PORT_FORWARDING_USERNAME= \
     VPN_PORT_FORWARDING_PASSWORD= \
+    VPN_PORT_FORWARDING_UP_COMMAND= \
+    VPN_PORT_FORWARDING_DOWN_COMMAND= \
     # # Cyberghost only:
     OPENVPN_CERT= \
     OPENVPN_KEY= \
@@ -161,20 +163,23 @@ ENV VPN_SERVICE_PROVIDER=pia \
     LOG_LEVEL=info \
     # Health
     HEALTH_SERVER_ADDRESS=127.0.0.1:9999 \
-    HEALTH_TARGET_ADDRESS=cloudflare.com:443 \
-    HEALTH_SUCCESS_WAIT_DURATION=5s \
-    HEALTH_VPN_DURATION_INITIAL=6s \
-    HEALTH_VPN_DURATION_ADDITION=5s \
-    # DNS over TLS
-    DOT=on \
-    DOT_PROVIDERS=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 \
-    DOT_CACHING=on \
-    DOT_IPV6=off \
+    HEALTH_TARGET_ADDRESSES=cloudflare.com:443,github.com:443 \
+    HEALTH_ICMP_TARGET_IPS=1.1.1.1,8.8.8.8 \
+    HEALTH_SMALL_CHECK_TYPE=icmp \
+    HEALTH_RESTART_VPN=on \
+    # DNS
+    DNS_SERVER=on \
+    DNS_UPSTREAM_RESOLVER_TYPE=DoT \
+    DNS_UPSTREAM_RESOLVERS=cloudflare \
+    DNS_BLOCK_IPS= \
+    DNS_BLOCK_IP_PREFIXES= \
+    DNS_CACHING=on \
+    DNS_UPSTREAM_IPV6=off \
     BLOCK_MALICIOUS=on \
     BLOCK_SURVEILLANCE=off \
     BLOCK_ADS=off \
-    UNBLOCK= \
+    DNS_UNBLOCK_HOSTNAMES= \
+    DNS_REBINDING_PROTECTION_EXEMPT_HOSTNAMES= \
     DNS_UPDATE_PERIOD=24h \
     DNS_ADDRESS=127.0.0.1 \
     DNS_KEEP_NAMESERVER=off \
@@ -198,10 +203,13 @@ ENV VPN_SERVICE_PROVIDER=pia \
     HTTP_CONTROL_SERVER_LOG=on \
     HTTP_CONTROL_SERVER_ADDRESS=":8000" \
     HTTP_CONTROL_SERVER_AUTH_CONFIG_FILEPATH=/gluetun/auth/config.toml \
+    HTTP_CONTROL_SERVER_AUTH_DEFAULT_ROLE="{}" \
     # Server data updater
     UPDATER_PERIOD=0 \
     UPDATER_MIN_RATIO=0.8 \
     UPDATER_VPN_SERVICE_PROVIDERS= \
+    UPDATER_PROTONVPN_EMAIL= \
+    UPDATER_PROTONVPN_PASSWORD= \
     # Public IP
     PUBLICIP_FILE="/tmp/gluetun/ip" \
     PUBLICIP_ENABLED=on \
@@ -217,8 +225,8 @@ ENV VPN_SERVICE_PROVIDER=pia \
     # Extras
     VERSION_INFORMATION=on \
     TZ= \
-    PUID= \
-    PGID=
+    PUID=1000 \
+    PGID=1000
 ENTRYPOINT ["/gluetun-entrypoint"]
 EXPOSE 8000/tcp 8888/tcp 8388/tcp 8388/udp
 HEALTHCHECK --interval=5s --timeout=5s --start-period=10s --retries=3 CMD /gluetun-entrypoint healthcheck

README.md

@@ -1,6 +1,8 @@
 # Gluetun VPN client
 
-Lightweight swiss-knife-like VPN client to multiple VPN service providers
+⚠️ This and [gluetun-wiki](https://github.com/qdm12/gluetun-wiki) are the only websites for Gluetun, other websites claiming to be official are scams ⚠️
+
+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 +28,6 @@ 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 +57,7 @@ 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 +89,7 @@ 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 +1,35 @@
+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)
+	case "protonvpn":
+		err = internal.ProtonVPNTest(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=
+github.com/Microsoft/go-winio v0.6.2 h1:F2VQgta7ecxGYO8k3ZZz3RS8fVIXVxONVUPlNERoyfY=
+github.com/Microsoft/go-winio v0.6.2/go.mod h1:yd8OoFMLzJbo9gZq8j5qaps8bJ9aShtEA8Ipt1oGCvU=
+github.com/cenkalti/backoff/v5 v5.0.3 h1:ZN+IMa753KfX5hd8vVaMixjnqRZ3y8CuJKRKj1xcsSM=
+github.com/cenkalti/backoff/v5 v5.0.3/go.mod h1:rkhZdG3JZukswDf7f0cwqPNk4K0sa+F97BxZthm/crw=
+github.com/containerd/errdefs v1.0.0 h1:tg5yIfIlQIrxYtu9ajqY42W3lpS19XqdxRQeEwYG8PI=
+github.com/containerd/errdefs v1.0.0/go.mod h1:+YBYIdtsnF4Iw6nWZhJcqGSg/dwvV7tyJ/kCkyJ2k+M=
+github.com/containerd/errdefs/pkg v0.3.0 h1:9IKJ06FvyNlexW690DXuQNx2KA2cUJXx151Xdx3ZPPE=
+github.com/containerd/errdefs/pkg v0.3.0/go.mod h1:NJw6s9HwNuRhnjJhM7pylWwMyAkmCQvQ4GpJHEqRLVk=
+github.com/containerd/log v0.1.0 h1:TCJt7ioM2cr/tfR8GPbGf9/VRAX8D2B4PjzCpfX540I=
+github.com/containerd/log v0.1.0/go.mod h1:VRRf09a7mHDIRezVKTRCrOq78v577GXq3bSa3EhrzVo=
+github.com/davecgh/go-spew v1.1.1 h1:vj9j/u1bqnvCEfJOwUhtlOARqs3+rkHYY13jYWTU97c=
+github.com/davecgh/go-spew v1.1.1/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
+github.com/distribution/reference v0.6.0 h1:0IXCQ5g4/QMHHkarYzh5l+u8T3t73zM5QvfrDyIgxBk=
+github.com/distribution/reference v0.6.0/go.mod h1:BbU0aIcezP1/5jX/8MP0YiH4SdvB5Y4f/wlDRiLyi3E=
+github.com/docker/docker v28.5.1+incompatible h1:Bm8DchhSD2J6PsFzxC35TZo4TLGR2PdW/E69rU45NhM=
+github.com/docker/docker v28.5.1+incompatible/go.mod h1:eEKB0N0r5NX/I1kEveEz05bcu8tLC/8azJZsviup8Sk=
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+github.com/docker/go-connections v0.6.0/go.mod h1:AahvXYshr6JgfUJGdDCs2b5EZG/vmaMAntpSFH5BFKE=
+github.com/docker/go-units v0.5.0 h1:69rxXcBk27SvSaaxTtLh/8llcHD8vYHT7WSdRZ/jvr4=
+github.com/docker/go-units v0.5.0/go.mod h1:fgPhTUdO+D/Jk86RDLlptpiXQzgHJF7gydDDbaIK4Dk=
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+github.com/go-logr/logr v1.4.3 h1:CjnDlHq8ikf6E492q6eKboGOC0T8CDaOvkHCIg8idEI=
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+github.com/grpc-ecosystem/grpc-gateway/v2 v2.27.2 h1:8Tjv8EJ+pM1xP8mK6egEbD1OgnVTyacbefKhmbLhIhU=
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+github.com/moby/docker-image-spec v1.3.1 h1:jMKff3w6PgbfSa69GfNg+zN/XLhfXJGnEx3Nl2EsFP0=
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+github.com/moby/sys/atomicwriter v0.1.0/go.mod h1:Ul8oqv2ZMNHOceF643P6FKPXeCmYtlQMvpizfsSoaWs=
+github.com/moby/sys/sequential v0.6.0 h1:qrx7XFUd/5DxtqcoH1h438hF5TmOvzC/lspjy7zgvCU=
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+github.com/opencontainers/image-spec v1.1.1 h1:y0fUlFfIZhPF1W537XOLg0/fcx6zcHCJwooC2xJA040=
+github.com/opencontainers/image-spec v1.1.1/go.mod h1:qpqAh3Dmcf36wStyyWU+kCeDgrGnAve2nCC8+7h8Q0M=
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+github.com/pkg/errors v0.9.1/go.mod h1:bwawxfHBFNV+L2hUp1rHADufV3IMtnDRdf1r5NINEl0=
+github.com/pmezard/go-difflib v1.0.0 h1:4DBwDE0NGyQoBHbLQYPwSUPoCMWR5BEzIk/f1lZbAQM=
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+github.com/sirupsen/logrus v1.9.3 h1:dueUQJ1C2q9oE3F7wvmSGAaVtTmUizReu6fjN8uqzbQ=
+github.com/sirupsen/logrus v1.9.3/go.mod h1:naHLuLoDiP4jHNo9R0sCBMtWGeIprob74mVsIT4qYEQ=
+github.com/stretchr/testify v1.11.1 h1:7s2iGBzp5EwR7/aIZr8ao5+dra3wiQyKjjFuvgVKu7U=
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+go.opentelemetry.io/auto/sdk v1.1.0 h1:cH53jehLUN6UFLY71z+NDOiNJqDdPRaXzTel0sJySYA=
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+go.opentelemetry.io/contrib/instrumentation/net/http/otelhttp v0.63.0/go.mod h1:h06DGIukJOevXaj/xrNjhi/2098RZzcLTbc0jDAUbsg=
+go.opentelemetry.io/otel v1.38.0 h1:RkfdswUDRimDg0m2Az18RKOsnI8UDzppJAtj01/Ymk8=
+go.opentelemetry.io/otel v1.38.0/go.mod h1:zcmtmQ1+YmQM9wrNsTGV/q/uyusom3P8RxwExxkZhjM=
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+go.opentelemetry.io/otel/exporters/otlp/otlptrace/otlptracehttp v1.38.0/go.mod h1:kldtb7jDTeol0l3ewcmd8SDvx3EmIE7lyvqbasU3QC4=
+go.opentelemetry.io/otel/metric v1.38.0 h1:Kl6lzIYGAh5M159u9NgiRkmoMKjvbsKtYRwgfrA6WpA=
+go.opentelemetry.io/otel/metric v1.38.0/go.mod h1:kB5n/QoRM8YwmUahxvI3bO34eVtQf2i4utNVLr9gEmI=
+go.opentelemetry.io/otel/sdk v1.38.0 h1:l48sr5YbNf2hpCUj/FoGhW9yDkl+Ma+LrVl8qaM5b+E=
+go.opentelemetry.io/otel/sdk v1.38.0/go.mod h1:ghmNdGlVemJI3+ZB5iDEuk4bWA3GkTpW+DOoZMYBVVg=
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+go.opentelemetry.io/otel/trace v1.38.0 h1:Fxk5bKrDZJUH+AMyyIXGcFAPah0oRcT+LuNtJrmcNLE=
+go.opentelemetry.io/otel/trace v1.38.0/go.mod h1:j1P9ivuFsTceSWe1oY+EeW3sc+Pp42sO++GHkg4wwhs=
+go.opentelemetry.io/proto/otlp v1.7.1 h1:gTOMpGDb0WTBOP8JaO72iL3auEZhVmAQg4ipjOVAtj4=
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+golang.org/x/net v0.43.0 h1:lat02VYK2j4aLzMzecihNvTlJNQUq316m2Mr9rnM6YE=
+golang.org/x/net v0.43.0/go.mod h1:vhO1fvI4dGsIjh73sWfUVjj3N7CA9WkKJNQm2svM6Jg=
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+google.golang.org/genproto/googleapis/rpc v0.0.0-20250825161204-c5933d9347a5 h1:eaY8u2EuxbRv7c3NiGK0/NedzVsCcV6hDuU5qPX5EGE=
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+google.golang.org/grpc v1.75.0 h1:+TW+dqTd2Biwe6KKfhE5JpiYIBWq865PhKGSXiivqt4=
+google.golang.org/grpc v1.75.0/go.mod h1:JtPAzKiq4v1xcAB2hydNlWI2RnF85XXcV0mhKXr2ecQ=
+google.golang.org/protobuf v1.36.8 h1:xHScyCOEuuwZEc6UtSOvPbAT4zRh0xcNRYekJwfqyMc=
+google.golang.org/protobuf v1.36.8/go.mod h1:fuxRtAxBytpl4zzqUh6/eyUujkJdNiuEkXntxiD/uRU=
+gopkg.in/yaml.v3 v3.0.1 h1:fxVm/GzAzEWqLHuvctI91KS9hhNmmWOoWu0XTYJS7CA=
+gopkg.in/yaml.v3 v3.0.1/go.mod h1:K4uyk7z7BCEPqu6E+C64Yfv1cQ7kz7rIZviUmN+EgEM=
+gotest.tools/v3 v3.5.2 h1:7koQfIKdy+I8UTetycgUqXWSDwpgv193Ka+qRsmBY8Q=
+gotest.tools/v3 v3.5.2/go.mod h1:LtdLGcnqToBH83WByAAi/wiwSFCArdFIUV/xxN4pcjA=

ci/internal/mullvad.go

@@ -0,0 +1,27 @@
+package internal
+
+import (
+	"context"
+	"fmt"
+)
+
+func MullvadTest(ctx context.Context) error {
+	expectedSecrets := []string{
+		"Wireguard private key",
+		"Wireguard address",
+	}
+	secrets, err := readSecrets(ctx, expectedSecrets)
+	if err != nil {
+		return fmt.Errorf("reading secrets: %w", err)
+	}
+
+	env := []string{
+		"VPN_SERVICE_PROVIDER=mullvad",
+		"VPN_TYPE=wireguard",
+		"LOG_LEVEL=debug",
+		"SERVER_COUNTRIES=USA",
+		"WIREGUARD_PRIVATE_KEY=" + secrets[0],
+		"WIREGUARD_ADDRESSES=" + secrets[1],
+	}
+	return simpleTest(ctx, env)
+}

ci/internal/protonvpn.go

@@ -0,0 +1,25 @@
+package internal
+
+import (
+	"context"
+	"fmt"
+)
+
+func ProtonVPNTest(ctx context.Context) error {
+	expectedSecrets := []string{
+		"Wireguard private key",
+	}
+	secrets, err := readSecrets(ctx, expectedSecrets)
+	if err != nil {
+		return fmt.Errorf("reading secrets: %w", err)
+	}
+
+	env := []string{
+		"VPN_SERVICE_PROVIDER=protonvpn",
+		"VPN_TYPE=wireguard",
+		"LOG_LEVEL=debug",
+		"SERVER_COUNTRIES=United States",
+		"WIREGUARD_PRIVATE_KEY=" + secrets[0],
+	}
+	return simpleTest(ctx, env)
+}

ci/internal/secrets.go

@@ -0,0 +1,42 @@
+package internal
+
+import (
+	"bufio"
+	"context"
+	"fmt"
+	"os"
+	"strings"
+)
+
+func readSecrets(ctx context.Context, expectedSecrets []string) (lines []string, err error) {
+	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()))
+		fmt.Println("🤫 "+expectedSecrets[i], "secret read successfully")
+		if ctx.Err() != nil {
+			return nil, ctx.Err()
+		}
+	}
+
+	if err := scanner.Err(); err != nil {
+		return nil, fmt.Errorf("reading secrets from stdin: %w", err)
+	}
+
+	if len(lines) < len(expectedSecrets) {
+		return nil, fmt.Errorf("expected %d secrets via Stdin, but only received %d",
+			len(expectedSecrets), len(lines))
+	}
+	for i, line := range lines {
+		if line == "" {
+			return nil, fmt.Errorf("secret on line %d/%d was empty", i+1, len(lines))
+		}
+	}
+
+	return lines, nil
+}

ci/internal/simple.go

@@ -0,0 +1,134 @@
+package internal
+
+import (
+	"bufio"
+	"context"
+	"fmt"
+	"io"
+	"regexp"
+	"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 ptrTo[T any](v T) *T { return &v }
+
+func simpleTest(ctx context.Context, env []string) error {
+	const timeout = 30 * 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:         env,
+	}
+	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 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

@@ -164,6 +164,8 @@ func _main(ctx context.Context, buildInfo models.BuildInformation,
 		}
 	}
 
+	defer fmt.Println(gluetunLogo)
+
 	announcementExp, err := time.Parse(time.RFC3339, "2024-12-01T00:00:00Z")
 	if err != nil {
 		return err
@@ -380,7 +382,7 @@ func _main(ctx context.Context, buildInfo models.BuildInformation,
 
 	portForwardLogger := logger.New(log.SetComponent("port forwarding"))
 	portForwardLooper := portforward.NewLoop(allSettings.VPN.Provider.PortForwarding,
-		routingConf, httpClient, firewallConf, portForwardLogger, puid, pgid)
+		routingConf, httpClient, firewallConf, portForwardLogger, cmder, puid, pgid)
 	portForwardRunError, err := portForwardLooper.Start(ctx)
 	if err != nil {
 		return fmt.Errorf("starting port forwarding loop: %w", err)
@@ -414,18 +416,26 @@ 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)
 	parallelResolver := resolver.NewParallelResolver(allSettings.Updater.DNSAddress)
 	openvpnFileExtractor := extract.New()
 	providers := provider.NewProviders(storage, time.Now, updaterLogger,
-		httpClient, unzipper, parallelResolver, publicIPLooper.Fetcher(), openvpnFileExtractor)
+		httpClient, unzipper, parallelResolver, publicIPLooper.Fetcher(),
+		openvpnFileExtractor, allSettings.Updater)
 
 	vpnLogger := logger.New(log.SetComponent("vpn"))
 	vpnLooper := vpn.NewLoop(allSettings.VPN, ipv6Supported, allSettings.Firewall.VPNInputPorts,
-		providers, storage, ovpnConf, netLinker, firewallConf, routingConf, portForwardLooper,
-		cmder, publicIPLooper, dnsLooper, vpnLogger, httpClient,
+		providers, storage, allSettings.Health, healthChecker, healthcheckServer, ovpnConf, netLinker, firewallConf,
+		routingConf, portForwardLooper, cmder, publicIPLooper, dnsLooper, vpnLogger, httpClient,
 		buildInfo, *allSettings.Version.Enabled)
 	vpnHandler, vpnCtx, vpnDone := goshutdown.NewGoRoutineHandler(
 		"vpn", goroutine.OptionTimeout(time.Second))
@@ -459,13 +469,10 @@ func _main(ctx context.Context, buildInfo models.BuildInformation,
 	go shadowsocksLooper.Run(shadowsocksCtx, shadowsocksDone)
 	otherGroupHandler.Add(shadowsocksHandler)
 
-	controlServerAddress := *allSettings.ControlServer.Address
-	controlServerLogging := *allSettings.ControlServer.Log
 	httpServerHandler, httpServerCtx, httpServerDone := goshutdown.NewGoRoutineHandler(
 		"http server", goroutine.OptionTimeout(defaultShutdownTimeout))
-	httpServer, err := server.New(httpServerCtx, controlServerAddress, controlServerLogging,
+	httpServer, err := server.New(httpServerCtx, allSettings.ControlServer,
 		logger.New(log.SetComponent("http server")),
-		allSettings.ControlServer.AuthFilePath,
 		buildInfo, vpnLooper, portForwardLooper, dnsLooper, updaterLooper, publicIPLooper,
 		storage, ipv6Supported)
 	if err != nil {
@@ -476,12 +483,6 @@ 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),
@@ -601,3 +602,34 @@ type RunStarter interface {
 	Start(cmd *exec.Cmd) (stdoutLines, stderrLines <-chan string,
 		waitError <-chan error, err error)
 }
+
+const gluetunLogo = `                         @@@
+                         @@@@
+                        @@@@@@
+                       @@@@.@@                       @@@@@@@@@@
+                       @@@@.@@@                   @@@@@@@@==@@@@
+                      @@@.@..@@                @@@@@@@=@..==@@@@
+            @@@@      @@@.@@.@@              @@@@@@===@@@@.=@@@
+           @...-@@   @@@@.@@.@@@  @@@     @@@@@@=======@@@=@@@@
+           @@@@@@@@  @@@.-%@.+@@@@@@@@  @@@@@%============@@@@
+                     @@@.--@..@@@@.-@@@@@@@==============@@@@
+              @@@@  @@@-@--@@.@@.---@@@@@==============#@@@@@
+              @@@   @@@.@@-@@.@@--@@@@@===============@@@@@@
+                   @@@@.@--@@@@@@@@@@================@@@@@@@
+                   @@@..--@@*@@@@@@================@@@@+*@@
+                   @@@.---@@.@@@@=================@@@@--@@
+                  @@@-.---@@@@@@================@@@@*--@@@
+                  @@@.:-#@@@@@@===============*@@@@.---@@
+                  @@@.-------.@@@============@@@@@@.--@@@
+                 @@@..--------:@@@=========@@@@@@@@.--@@@
+                 @@@.-@@@@@@@@@@@========@@@@@  @@@.--@@
+                 @@.@@@@===============@@@@@ @@@@@@---@@@@@@
+                @@@@@@@==============@@@@@@@@@@@@*@---@@@@@@@@
+                @@@@@@=============@@@@@ @@@...------------.*@@@
+                @@@@%===========@@@@@@ @@@..------@@@@.-----.-@@@
+                @@@@@@.=======@@@@@@  @@@.-------@@@@@@-.------=@@
+               @@@@@@@@@===@@@@@@     @@.------@@@@   @@@@.-----@@@
+               @@@==@@@=@@@@@@@      @@@.-@@@@@@@       @@@@@@@--@@
+               @@@@@@@@@@@@@         @@@@@@@@                @@@@@@@
+                @@@@@@@@             @@@@                       @@@@
+                                                                       `

go.mod

@@ -1,37 +1,42 @@
 module github.com/qdm12/gluetun
 
-go 1.23
+go 1.25.0
 
 require (
-	github.com/breml/rootcerts v0.2.18
+	github.com/ProtonMail/go-srp v0.0.7
+	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/qdm12/dns/v2 v2.0.0-rc8
-	github.com/qdm12/gosettings v0.4.3
+	github.com/pelletier/go-toml/v2 v2.2.4
+	github.com/qdm12/dns/v2 v2.0.0-rc9.0.20251123213823-54e987293e88
+	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 v1.9.0
-	github.com/ulikunitz/xz v0.5.11
-	github.com/vishvananda/netlink v1.2.1
+	github.com/stretchr/testify v1.11.1
+	github.com/ulikunitz/xz v0.5.15
+	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 v0.30.0
-	golang.org/x/sys v0.27.0
-	golang.org/x/text v0.19.0
+	golang.org/x/net v0.47.0
+	golang.org/x/sys v0.38.0
+	golang.org/x/text v0.31.0
 	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
 )
 
 require (
+	github.com/ProtonMail/bcrypt v0.0.0-20211005172633-e235017c1baf // indirect
+	github.com/ProtonMail/go-crypto v1.3.0-proton // indirect
 	github.com/beorn7/perks v1.0.1 // indirect
 	github.com/cespare/xxhash/v2 v2.3.0 // indirect
+	github.com/cloudflare/circl v1.6.1 // indirect
+	github.com/cronokirby/saferith v0.33.0 // indirect
 	github.com/davecgh/go-spew v1.1.1 // indirect
 	github.com/google/go-cmp v0.6.0 // indirect
 	github.com/josharian/native v1.1.0 // indirect
@@ -42,18 +47,20 @@ require (
 	github.com/mdlayher/socket v0.4.1 // indirect
 	github.com/miekg/dns v1.1.62 // indirect
 	github.com/munnerz/goautoneg v0.0.0-20191010083416-a7dc8b61c822 // indirect
+	github.com/pkg/errors v0.9.1 // indirect
 	github.com/pmezard/go-difflib v1.0.0 // indirect
 	github.com/prometheus/client_golang v1.20.5 // indirect
 	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
-	golang.org/x/crypto v0.28.0 // indirect
-	golang.org/x/mod v0.21.0 // indirect
-	golang.org/x/sync v0.8.0 // indirect
-	golang.org/x/tools v0.26.0 // indirect
+	github.com/vishvananda/netns v0.0.5 // indirect
+	golang.org/x/crypto v0.45.0 // indirect
+	golang.org/x/mod v0.29.0 // indirect
+	golang.org/x/sync v0.18.0 // indirect
+	golang.org/x/time v0.3.0 // indirect
+	golang.org/x/tools v0.38.0 // 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

@@ -1,9 +1,23 @@
+github.com/ProtonMail/bcrypt v0.0.0-20210511135022-227b4adcab57/go.mod h1:HecWFHognK8GfRDGnFQbW/LiV7A3MX3gZVs45vk5h8I=
+github.com/ProtonMail/bcrypt v0.0.0-20211005172633-e235017c1baf h1:yc9daCCYUefEs69zUkSzubzjBbL+cmOXgnmt9Fyd9ug=
+github.com/ProtonMail/bcrypt v0.0.0-20211005172633-e235017c1baf/go.mod h1:o0ESU9p83twszAU8LBeJKFAAMX14tISa0yk4Oo5TOqo=
+github.com/ProtonMail/go-crypto v0.0.0-20230321155629-9a39f2531310/go.mod h1:8TI4H3IbrackdNgv+92dI+rhpCaLqM0IfpgCgenFvRE=
+github.com/ProtonMail/go-crypto v1.3.0-proton h1:tAQKQRZX/73VmzK6yHSCaRUOvS/3OYSQzhXQsrR7yUM=
+github.com/ProtonMail/go-crypto v1.3.0-proton/go.mod h1:9whxjD8Rbs29b4XWbB8irEcE8KHMqaR2e7GWU1R+/PE=
+github.com/ProtonMail/go-srp v0.0.7 h1:Sos3Qk+th4tQR64vsxGIxYpN3rdnG9Wf9K4ZloC1JrI=
+github.com/ProtonMail/go-srp v0.0.7/go.mod h1:giCp+7qRnMIcCvI6V6U3S1lDDXDQYx2ewJ6F/9wdlJk=
 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 v0.2.18 h1:KjZaNT7AX/akUjzpStuwTMQs42YHlPyc6NmdwShVba0=
-github.com/breml/rootcerts v0.2.18/go.mod h1:S/PKh+4d1HUn4HQovEB8hPJZO6pUZYrIhmXBhsegfXw=
+github.com/breml/rootcerts v0.3.3 h1://GnaRtQ/9BY2+GtMk2wtWxVdCRysiaPr5/xBwl7NKw=
+github.com/breml/rootcerts v0.3.3/go.mod h1:S/PKh+4d1HUn4HQovEB8hPJZO6pUZYrIhmXBhsegfXw=
+github.com/bwesterb/go-ristretto v1.2.0/go.mod h1:fUIoIZaG73pV5biE2Blr2xEzDoMj7NFEuV9ekS419A0=
 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/cloudflare/circl v1.1.0/go.mod h1:prBCrKB9DV4poKZY1l9zBXg2QJY7mvgRvtMxxK7fi4I=
+github.com/cloudflare/circl v1.6.1 h1:zqIqSPIndyBh1bjLVVDHMPpVKqp8Su/V+6MeDzzQBQ0=
+github.com/cloudflare/circl v1.6.1/go.mod h1:uddAzsPgqdMAYatqJ0lsjX1oECcQLIlRpzZh3pJrofs=
+github.com/cronokirby/saferith v0.33.0 h1:TgoQlfsD4LIwx71+ChfRcIpjkw+RPOapDEVxa+LhwLo=
+github.com/cronokirby/saferith v0.33.0/go.mod h1:QKJhjoqUtBsXCAVEjw38mFqoi7DebT7kthcD7UzbnoA=
 github.com/davecgh/go-spew v1.1.1 h1:vj9j/u1bqnvCEfJOwUhtlOARqs3+rkHYY13jYWTU97c=
 github.com/davecgh/go-spew v1.1.1/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
 github.com/fatih/color v1.18.0 h1:S8gINlzdQ840/4pfAwic/ZE0djQEH3wM94VfqLTZcOM=
@@ -16,8 +30,8 @@ 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 v1.17.11/go.mod h1:pMDklpSncoRMuLFrf1W9Ss9KT+0rH90U12bZKk7uwG0=
+github.com/klauspost/compress v1.18.1 h1:bcSGx7UbpBqMChDtsF28Lw6v/G94LPrrbMbdC3JH2co=
+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 +55,10 @@ 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 v2.2.3/go.mod h1:MfCQTFTvCcUyyvvwm1+G6H/jORL20Xlb6rzQu9GuUkc=
+github.com/pelletier/go-toml/v2 v2.2.4 h1:mye9XuhQ6gvn5h28+VilKrrPoQVanw5PMw/TB0t5Ec4=
+github.com/pelletier/go-toml/v2 v2.2.4/go.mod h1:2gIqNv+qfxSVS7cM2xJQKtLSTLUE9V8t9Stt+h56mCY=
+github.com/pkg/errors v0.9.1 h1:FEBLx1zS214owpjy7qsBeixbURkuhQAwrK5UwLGTwt4=
+github.com/pkg/errors v0.9.1/go.mod h1:bwawxfHBFNV+L2hUp1rHADufV3IMtnDRdf1r5NINEl0=
 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=
@@ -53,12 +69,12 @@ 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-rc8/go.mod h1:VaF02KWEL7xNV4oKfG4N9nEv/kR6bqyIcBReCV5NJhw=
-github.com/qdm12/goservices v0.1.0 h1:9sODefm/yuIGS7ynCkEnNlMTAYn9GzPhtcK4F69JWvc=
-github.com/qdm12/goservices v0.1.0/go.mod h1:/JOFsAnHFiSjyoXxa5FlfX903h20K5u/3rLzCjYVMck=
-github.com/qdm12/gosettings v0.4.3 h1:oGAjiKVtml9oHVlPQo6H3yk6TmtWpVYicNeGFcM7AP8=
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 github.com/qdm12/goshutdown v0.3.0 h1:pqBpJkdwlZlfTEx4QHtS8u8CXx6pG0fVo6S1N0MpSEM=
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 github.com/qdm12/gosplash v0.2.0 h1:DOxCEizbW6ZG+FgpH2oK1atT6bM8MHL9GZ2ywSS4zZY=
@@ -73,59 +89,83 @@ 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=
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 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=
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 golang.org/x/sys v0.0.0-20201119102817-f84b799fce68/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
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 golang.org/x/sys v0.0.0-20210510120138-977fb7262007/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
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 golang.org/x/sys v0.0.0-20220811171246-fbc7d0a398ab/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
 golang.org/x/sys v0.2.0/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
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 golang.org/x/sys v0.10.0/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
-golang.org/x/sys v0.27.0 h1:wBqf8DvsY9Y/2P8gAfPDEYNuS30J4lPHJxXSb/nJZ+s=
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-golang.org/x/tools v0.26.0 h1:v/60pFQmzmT9ExmjDv2gGIfi3OqfKoEP6I5+umXlbnQ=
-golang.org/x/tools v0.26.0/go.mod h1:TPVVj70c7JJ3WCazhD8OdXcZg/og+b9+tH/KxylGwH0=
+golang.org/x/tools v0.1.12/go.mod h1:hNGJHUnrk76NpqgfD5Aqm5Crs+Hm0VOH/i9J2+nxYbc=
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+golang.org/x/tools v0.38.0/go.mod h1:yEsQ/d/YK8cjh0L6rZlY8tgtlKiBNTL14pGDJPJpYQs=
 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/nooplogger.go

@@ -7,3 +7,4 @@ func newNoopLogger() *noopLogger {
 }
 
 func (l *noopLogger) Info(string) {}
+func (l *noopLogger) Warn(string) {}

internal/cli/openvpnconfig.go

@@ -56,6 +56,7 @@ func (c *CLI) OpenvpnConfig(logger OpenvpnConfigLogger, reader *reader.Reader,
 	if err != nil {
 		return err
 	}
+	allSettings.SetDefaults()
 
 	ipv6Supported, err := ipv6Checker.IsIPv6Supported()
 	if err != nil {
@@ -75,7 +76,7 @@ func (c *CLI) OpenvpnConfig(logger OpenvpnConfigLogger, reader *reader.Reader,
 	openvpnFileExtractor := extract.New()
 
 	providers := provider.NewProviders(storage, time.Now, warner, client,
-		unzipper, parallelResolver, ipFetcher, openvpnFileExtractor)
+		unzipper, parallelResolver, ipFetcher, openvpnFileExtractor, allSettings.Updater)
 	providerConf := providers.Get(allSettings.VPN.Provider.Name)
 	connection, err := providerConf.GetConnection(
 		allSettings.VPN.Provider.ServerSelection, ipv6Supported)

internal/cli/update.go

@@ -6,6 +6,7 @@ import (
 	"flag"
 	"fmt"
 	"net/http"
+	"slices"
 	"strings"
 	"time"
 
@@ -24,6 +25,8 @@ import (
 var (
 	ErrModeUnspecified     = errors.New("at least one of -enduser or -maintainer must be specified")
 	ErrNoProviderSpecified = errors.New("no provider was specified")
+	ErrUsernameMissing     = errors.New("username is required for this provider")
+	ErrPasswordMissing     = errors.New("password is required for this provider")
 )
 
 type UpdaterLogger interface {
@@ -35,7 +38,7 @@ type UpdaterLogger interface {
 func (c *CLI) Update(ctx context.Context, args []string, logger UpdaterLogger) error {
 	options := settings.Updater{}
 	var endUserMode, maintainerMode, updateAll bool
-	var csvProviders, ipToken string
+	var csvProviders, ipToken, protonUsername, protonEmail, protonPassword string
 	flagSet := flag.NewFlagSet("update", flag.ExitOnError)
 	flagSet.BoolVar(&endUserMode, "enduser", false, "Write results to /gluetun/servers.json (for end users)")
 	flagSet.BoolVar(&maintainerMode, "maintainer", false,
@@ -47,6 +50,10 @@ func (c *CLI) Update(ctx context.Context, args []string, logger UpdaterLogger) e
 	flagSet.BoolVar(&updateAll, "all", false, "Update servers for all VPN providers")
 	flagSet.StringVar(&csvProviders, "providers", "", "CSV string of VPN providers to update server data for")
 	flagSet.StringVar(&ipToken, "ip-token", "", "IP data service token (e.g. ipinfo.io) to use")
+	flagSet.StringVar(&protonUsername, "proton-username", "",
+		"(Retro-compatibility) Username to use to authenticate with Proton. Use -proton-email instead.") // v4 remove this
+	flagSet.StringVar(&protonEmail, "proton-email", "", "Email to use to authenticate with Proton")
+	flagSet.StringVar(&protonPassword, "proton-password", "", "Password to use to authenticate with Proton")
 	if err := flagSet.Parse(args); err != nil {
 		return err
 	}
@@ -64,6 +71,16 @@ func (c *CLI) Update(ctx context.Context, args []string, logger UpdaterLogger) e
 		options.Providers = strings.Split(csvProviders, ",")
 	}
 
+	if slices.Contains(options.Providers, providers.Protonvpn) {
+		if protonEmail == "" && protonUsername != "" {
+			protonEmail = protonUsername + "@protonmail.com"
+			logger.Warn("use -proton-email instead of -proton-username in the future. " +
+				"This assumes the email is " + protonEmail + " and may not work.")
+		}
+		options.ProtonEmail = &protonEmail
+		options.ProtonPassword = &protonPassword
+	}
+
 	options.SetDefaults(options.Providers[0])
 
 	err := options.Validate()
@@ -71,7 +88,11 @@ func (c *CLI) Update(ctx context.Context, args []string, logger UpdaterLogger) e
 		return fmt.Errorf("options validation failed: %w", err)
 	}
 
-	storage, err := storage.New(logger, constants.ServersData)
+	serversDataPath := constants.ServersData
+	if maintainerMode {
+		serversDataPath = ""
+	}
+	storage, err := storage.New(logger, serversDataPath)
 	if err != nil {
 		return fmt.Errorf("creating servers storage: %w", err)
 	}
@@ -94,7 +115,7 @@ func (c *CLI) Update(ctx context.Context, args []string, logger UpdaterLogger) e
 	openvpnFileExtractor := extract.New()
 
 	providers := provider.NewProviders(storage, time.Now, logger, httpClient,
-		unzipper, parallelResolver, ipFetcher, openvpnFileExtractor)
+		unzipper, parallelResolver, ipFetcher, openvpnFileExtractor, options)
 
 	updater := updater.New(httpClient, storage, providers, logger)
 	err = updater.UpdateServers(ctx, options.Providers, options.MinRatio)

internal/command/split.go

@@ -0,0 +1,150 @@
+package command
+
+import (
+	"bytes"
+	"errors"
+	"fmt"
+	"strings"
+	"unicode/utf8"
+)
+
+var (
+	ErrCommandEmpty            = errors.New("command is empty")
+	ErrSingleQuoteUnterminated = errors.New("unterminated single-quoted string")
+	ErrDoubleQuoteUnterminated = errors.New("unterminated double-quoted string")
+	ErrEscapeUnterminated      = errors.New("unterminated backslash-escape")
+)
+
+// Split splits a command string into a slice of arguments.
+// This is especially important for commands such as:
+// /bin/sh -c "echo hello"
+// which should be split into: ["/bin/sh", "-c", "echo hello"]
+// It supports backslash-escapes, single-quotes and double-quotes.
+// It does not support:
+// - the $" quoting style.
+// - expansion (brace, shell or pathname).
+func Split(command string) (words []string, err error) {
+	if command == "" {
+		return nil, fmt.Errorf("%w", ErrCommandEmpty)
+	}
+
+	const bufferSize = 1024
+	buffer := bytes.NewBuffer(make([]byte, bufferSize))
+
+	startIndex := 0
+
+	for startIndex < len(command) {
+		// skip any split characters at the start
+		character, runeSize := utf8.DecodeRuneInString(command[startIndex:])
+		switch {
+		case strings.ContainsRune(" \n\t", character):
+			startIndex += runeSize
+		case character == '\\':
+			// Look ahead to eventually skip an escaped newline
+			if command[startIndex+runeSize:] == "" {
+				return nil, fmt.Errorf("%w: %q", ErrEscapeUnterminated, command)
+			}
+			character, runeSize := utf8.DecodeRuneInString(command[startIndex+runeSize:])
+			if character == '\n' {
+				startIndex += runeSize + runeSize // backslash and newline
+			}
+		default:
+			var word string
+			buffer.Reset()
+			word, startIndex, err = splitWord(command, startIndex, buffer)
+			if err != nil {
+				return nil, fmt.Errorf("splitting word in %q: %w", command, err)
+			}
+			words = append(words, word)
+		}
+	}
+	return words, nil
+}
+
+// WARNING: buffer must be cleared before calling this function.
+func splitWord(input string, startIndex int, buffer *bytes.Buffer) (
+	word string, newStartIndex int, err error,
+) {
+	cursor := startIndex
+	for cursor < len(input) {
+		character, runeLength := utf8.DecodeRuneInString(input[cursor:])
+		cursor += runeLength
+		if character == '"' ||
+			character == '\'' ||
+			character == '\\' ||
+			character == ' ' ||
+			character == '\n' ||
+			character == '\t' {
+			buffer.WriteString(input[startIndex : cursor-runeLength])
+		}
+
+		switch {
+		case strings.ContainsRune(" \n\t", character): // spacing character
+			return buffer.String(), cursor, nil
+		case character == '"':
+			return handleDoubleQuoted(input, cursor, buffer)
+		case character == '\'':
+			return handleSingleQuoted(input, cursor, buffer)
+		case character == '\\':
+			return handleEscaped(input, cursor, buffer)
+		}
+	}
+
+	buffer.WriteString(input[startIndex:])
+	return buffer.String(), len(input), nil
+}
+
+func handleDoubleQuoted(input string, startIndex int, buffer *bytes.Buffer) (
+	word string, newStartIndex int, err error,
+) {
+	cursor := startIndex
+	for cursor < len(input) {
+		nextCharacter, nextRuneLength := utf8.DecodeRuneInString(input[cursor:])
+		cursor += nextRuneLength
+		switch nextCharacter {
+		case '"': // end of the double quoted string
+			buffer.WriteString(input[startIndex : cursor-nextRuneLength])
+			return splitWord(input, cursor, buffer)
+		case '\\': // escaped character
+			escapedCharacter, escapedRuneLength := utf8.DecodeRuneInString(input[cursor:])
+			cursor += escapedRuneLength
+			if !strings.ContainsRune("$`\"\n\\", escapedCharacter) {
+				break
+			}
+			buffer.WriteString(input[startIndex : cursor-nextRuneLength-escapedRuneLength])
+			if escapedCharacter != '\n' {
+				// skip backslash entirely for the newline character
+				buffer.WriteRune(escapedCharacter)
+			}
+			startIndex = cursor
+		}
+	}
+	return "", 0, fmt.Errorf("%w", ErrDoubleQuoteUnterminated)
+}
+
+func handleSingleQuoted(input string, startIndex int, buffer *bytes.Buffer) (
+	word string, newStartIndex int, err error,
+) {
+	closingQuoteIndex := strings.IndexRune(input[startIndex:], '\'')
+	if closingQuoteIndex == -1 {
+		return "", 0, fmt.Errorf("%w", ErrSingleQuoteUnterminated)
+	}
+	buffer.WriteString(input[startIndex : startIndex+closingQuoteIndex])
+	const singleQuoteRuneLength = 1
+	startIndex += closingQuoteIndex + singleQuoteRuneLength
+	return splitWord(input, startIndex, buffer)
+}
+
+func handleEscaped(input string, startIndex int, buffer *bytes.Buffer) (
+	word string, newStartIndex int, err error,
+) {
+	if input[startIndex:] == "" {
+		return "", 0, fmt.Errorf("%w", ErrEscapeUnterminated)
+	}
+	character, runeLength := utf8.DecodeRuneInString(input[startIndex:])
+	if character != '\n' { // backslash-escaped newline is ignored
+		buffer.WriteString(input[startIndex : startIndex+runeLength])
+	}
+	startIndex += runeLength
+	return splitWord(input, startIndex, buffer)
+}

internal/command/split_test.go

@@ -0,0 +1,110 @@
+package command
+
+import (
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+)
+
+func Test_Split(t *testing.T) {
+	t.Parallel()
+
+	testCases := map[string]struct {
+		command    string
+		words      []string
+		errWrapped error
+		errMessage string
+	}{
+		"empty": {
+			command:    "",
+			errWrapped: ErrCommandEmpty,
+			errMessage: "command is empty",
+		},
+		"concrete_sh_command": {
+			command: `/bin/sh -c "echo 123"`,
+			words:   []string{"/bin/sh", "-c", "echo 123"},
+		},
+		"single_word": {
+			command: "word1",
+			words:   []string{"word1"},
+		},
+		"two_words_single_space": {
+			command: "word1 word2",
+			words:   []string{"word1", "word2"},
+		},
+		"two_words_multiple_space": {
+			command: "word1    word2",
+			words:   []string{"word1", "word2"},
+		},
+		"two_words_no_expansion": {
+			command: "word1*    word2?",
+			words:   []string{"word1*", "word2?"},
+		},
+		"escaped_single quote": {
+			command: "ain\\'t good",
+			words:   []string{"ain't", "good"},
+		},
+		"escaped_single_quote_all_single_quoted": {
+			command: "'ain'\\''t good'",
+			words:   []string{"ain't good"},
+		},
+		"empty_single_quoted": {
+			command: "word1 ''  word2",
+			words:   []string{"word1", "", "word2"},
+		},
+		"escaped_newline": {
+			command: "word1\\\nword2",
+			words:   []string{"word1word2"},
+		},
+		"quoted_newline": {
+			command: "text \"with\na\" quoted newline",
+			words:   []string{"text", "with\na", "quoted", "newline"},
+		},
+		"quoted_escaped_newline": {
+			command: "\"word1\\d\\\\\\\" word2\\\nword3 word4\"",
+			words:   []string{"word1\\d\\\" word2word3 word4"},
+		},
+		"escaped_separated_newline": {
+			command: "word1 \\\n word2",
+			words:   []string{"word1", "word2"},
+		},
+		"double_quotes_no_spacing": {
+			command: "word1\"word2\"word3",
+			words:   []string{"word1word2word3"},
+		},
+		"unterminated_single_quote": {
+			command:    "'abc'\\''def",
+			errWrapped: ErrSingleQuoteUnterminated,
+			errMessage: `splitting word in "'abc'\\''def": unterminated single-quoted string`,
+		},
+		"unterminated_double_quote": {
+			command:    "\"abc'def",
+			errWrapped: ErrDoubleQuoteUnterminated,
+			errMessage: `splitting word in "\"abc'def": unterminated double-quoted string`,
+		},
+		"unterminated_escape": {
+			command:    "abc\\",
+			errWrapped: ErrEscapeUnterminated,
+			errMessage: `splitting word in "abc\\": unterminated backslash-escape`,
+		},
+		"unterminated_escape_only": {
+			command:    "   \\",
+			errWrapped: ErrEscapeUnterminated,
+			errMessage: `unterminated backslash-escape: "   \\"`,
+		},
+	}
+
+	for name, testCase := range testCases {
+		t.Run(name, func(t *testing.T) {
+			t.Parallel()
+
+			words, err := Split(testCase.command)
+
+			assert.Equal(t, testCase.words, words)
+			assert.ErrorIs(t, err, testCase.errWrapped)
+			if testCase.errWrapped != nil {
+				assert.EqualError(t, err, testCase.errMessage)
+			}
+		})
+	}
+}

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_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_VERBOSITY":                "DOT_VERBOSITY is obsolete, use LOG_LEVEL instead.",
+		"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.",
+		"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.ServerAddress = gosettings.DefaultValidator(d.ServerAddress, localhost)
+	d.ServerEnabled = gosettings.DefaultPointer(d.ServerEnabled, true)
+	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

@@ -22,6 +22,9 @@ type DNSBlacklist struct {
 	AddBlockedHosts      []string
 	AddBlockedIPs        []netip.Addr
 	AddBlockedIPPrefixes []netip.Prefix
+	// RebindingProtectionExemptHostnames is a list of hostnames
+	// exempt from DNS rebinding protection.
+	RebindingProtectionExemptHostnames []string
 }
 
 func (b *DNSBlacklist) setDefaults() {
@@ -33,8 +36,9 @@ func (b *DNSBlacklist) setDefaults() {
 var hostRegex = regexp.MustCompile(`^([a-zA-Z0-9]|[a-zA-Z0-9_][a-zA-Z0-9\-_]{0,61}[a-zA-Z0-9_])(\.([a-zA-Z0-9]|[a-zA-Z0-9_][a-zA-Z0-9\-_]{0,61}[a-zA-Z0-9]))*$`) //nolint:lll
 
 var (
-	ErrAllowedHostNotValid = errors.New("allowed host is not valid")
-	ErrBlockedHostNotValid = errors.New("blocked host is not valid")
+	ErrAllowedHostNotValid                   = errors.New("allowed host is not valid")
+	ErrBlockedHostNotValid                   = errors.New("blocked host is not valid")
+	ErrRebindingProtectionExemptHostNotValid = errors.New("rebinding protection exempt host is not valid")
 )
 
 func (b DNSBlacklist) validate() (err error) {
@@ -50,18 +54,25 @@ func (b DNSBlacklist) validate() (err error) {
 		}
 	}
 
+	for _, host := range b.RebindingProtectionExemptHostnames {
+		if !hostRegex.MatchString(host) {
+			return fmt.Errorf("%w: %s", ErrRebindingProtectionExemptHostNotValid, host)
+		}
+	}
+
 	return nil
 }
 
 func (b DNSBlacklist) copy() (copied DNSBlacklist) {
 	return DNSBlacklist{
-		BlockMalicious:       gosettings.CopyPointer(b.BlockMalicious),
-		BlockAds:             gosettings.CopyPointer(b.BlockAds),
-		BlockSurveillance:    gosettings.CopyPointer(b.BlockSurveillance),
-		AllowedHosts:         gosettings.CopySlice(b.AllowedHosts),
-		AddBlockedHosts:      gosettings.CopySlice(b.AddBlockedHosts),
-		AddBlockedIPs:        gosettings.CopySlice(b.AddBlockedIPs),
-		AddBlockedIPPrefixes: gosettings.CopySlice(b.AddBlockedIPPrefixes),
+		BlockMalicious:                     gosettings.CopyPointer(b.BlockMalicious),
+		BlockAds:                           gosettings.CopyPointer(b.BlockAds),
+		BlockSurveillance:                  gosettings.CopyPointer(b.BlockSurveillance),
+		AllowedHosts:                       gosettings.CopySlice(b.AllowedHosts),
+		AddBlockedHosts:                    gosettings.CopySlice(b.AddBlockedHosts),
+		AddBlockedIPs:                      gosettings.CopySlice(b.AddBlockedIPs),
+		AddBlockedIPPrefixes:               gosettings.CopySlice(b.AddBlockedIPPrefixes),
+		RebindingProtectionExemptHostnames: gosettings.CopySlice(b.RebindingProtectionExemptHostnames),
 	}
 }
 
@@ -73,6 +84,8 @@ func (b *DNSBlacklist) overrideWith(other DNSBlacklist) {
 	b.AddBlockedHosts = gosettings.OverrideWithSlice(b.AddBlockedHosts, other.AddBlockedHosts)
 	b.AddBlockedIPs = gosettings.OverrideWithSlice(b.AddBlockedIPs, other.AddBlockedIPs)
 	b.AddBlockedIPPrefixes = gosettings.OverrideWithSlice(b.AddBlockedIPPrefixes, other.AddBlockedIPPrefixes)
+	b.RebindingProtectionExemptHostnames = gosettings.OverrideWithSlice(b.RebindingProtectionExemptHostnames,
+		other.RebindingProtectionExemptHostnames)
 }
 
 func (b DNSBlacklist) ToBlockBuilderSettings(client *http.Client) (
@@ -129,6 +142,13 @@ func (b DNSBlacklist) toLinesNode() (node *gotree.Node) {
 		}
 	}
 
+	if len(b.RebindingProtectionExemptHostnames) > 0 {
+		exemptHostsNode := node.Append("Rebinding protection exempt hostnames:")
+		for _, host := range b.RebindingProtectionExemptHostnames {
+			exemptHostsNode.Append(host)
+		}
+	}
+
 	return node
 }
 
@@ -149,23 +169,47 @@ func (b *DNSBlacklist) read(r *reader.Reader) (err error) {
 		return err
 	}
 
-	b.AddBlockedIPs, b.AddBlockedIPPrefixes,
-		err = readDoTPrivateAddresses(r) // TODO v4 split in 2
+	b.AddBlockedIPs, b.AddBlockedIPPrefixes, err = readDNSBlockedIPs(r)
 	if err != nil {
 		return err
 	}
 
-	b.AllowedHosts = r.CSV("UNBLOCK") // TODO v4 change name
+	b.AllowedHosts = r.CSV("DNS_UNBLOCK_HOSTNAMES", reader.RetroKeys("UNBLOCK"))
+
+	b.RebindingProtectionExemptHostnames = r.CSV("DNS_REBINDING_PROTECTION_EXEMPT_HOSTNAMES")
 
 	return nil
 }
 
-var ErrPrivateAddressNotValid = errors.New("private address is not a valid IP or CIDR range")
-
-func readDoTPrivateAddresses(reader *reader.Reader) (ips []netip.Addr,
+func readDNSBlockedIPs(r *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/errors.go

@@ -36,6 +36,8 @@ var (
 	ErrSystemPUIDNotValid              = errors.New("process user id is not valid")
 	ErrSystemTimezoneNotValid          = errors.New("timezone is not valid")
 	ErrUpdaterPeriodTooSmall           = errors.New("VPN server data updater period is too small")
+	ErrUpdaterProtonPasswordMissing    = errors.New("proton password is missing")
+	ErrUpdaterProtonEmailMissing       = errors.New("proton email is missing")
 	ErrVPNProviderNameNotValid         = errors.New("VPN provider name is not valid")
 	ErrVPNTypeNotValid                 = errors.New("VPN type is not valid")
 	ErrWireguardAllowedIPNotSet        = errors.New("allowed IP is not set")

internal/configuration/settings/health.go

@@ -1,9 +1,10 @@
 package settings
 
 import (
+	"errors"
 	"fmt"
+	"net/netip"
 	"os"
-	"time"
 
 	"github.com/qdm12/gosettings"
 	"github.com/qdm12/gosettings/reader"
@@ -17,34 +18,51 @@ type Health struct {
 	// for the health check server.
 	// It cannot be the empty string in the internal state.
 	ServerAddress string
-	// ReadHeaderTimeout is the HTTP server header read timeout
-	// duration of the HTTP server. It defaults to 100 milliseconds.
-	ReadHeaderTimeout time.Duration
-	// ReadTimeout is the HTTP read timeout duration of the
-	// HTTP server. It defaults to 500 milliseconds.
-	ReadTimeout time.Duration
-	// TargetAddress is the address (host or host:port)
-	// to TCP dial to periodically for the health check.
-	// It cannot be the empty string in the internal state.
-	TargetAddress string
-	// SuccessWait is the duration to wait to re-run the
-	// healthcheck after a successful healthcheck.
-	// It defaults to 5 seconds and cannot be zero in
-	// the internal state.
-	SuccessWait time.Duration
-	// VPN has health settings specific to the VPN loop.
-	VPN HealthyWait
+	// TargetAddresses are the addresses (host or host:port)
+	// to TCP TLS dial to periodically for the health check.
+	// Addresses after the first one are used as fallbacks for retries.
+	// It cannot be empty in the internal state.
+	TargetAddresses []string
+	// ICMPTargetIPs are the IP addresses to use for ICMP echo requests
+	// in the health checker. The slice can be set to a single
+	// unspecified address (0.0.0.0) such that the VPN server IP is used,
+	// although this can be less reliable. It defaults to [1.1.1.1,8.8.8.8],
+	// and cannot be left empty in the internal state.
+	ICMPTargetIPs []netip.Addr
+	// SmallCheckType is the type of small health check to perform.
+	// It can be "icmp" or "dns", and defaults to "icmp".
+	// Note it changes automatically to dns if icmp is not supported.
+	SmallCheckType string
+	// RestartVPN indicates whether to restart the VPN connection
+	// when the healthcheck fails.
+	RestartVPN *bool
 }
 
+var (
+	ErrICMPTargetIPNotValid       = errors.New("ICMP target IP address is not valid")
+	ErrICMPTargetIPsNotCompatible = errors.New("ICMP target IP addresses are not compatible")
+	ErrSmallCheckTypeNotValid     = errors.New("small check type is not valid")
+)
+
 func (h Health) Validate() (err error) {
 	err = validate.ListeningAddress(h.ServerAddress, os.Getuid())
 	if err != nil {
 		return fmt.Errorf("server listening address is not valid: %w", err)
 	}
 
-	err = h.VPN.validate()
+	for _, ip := range h.ICMPTargetIPs {
+		switch {
+		case !ip.IsValid():
+			return fmt.Errorf("%w: %s", ErrICMPTargetIPNotValid, ip)
+		case ip.IsUnspecified() && len(h.ICMPTargetIPs) > 1:
+			return fmt.Errorf("%w: only a single IP address must be set if it is to be unspecified",
+				ErrICMPTargetIPsNotCompatible)
+		}
+	}
+
+	err = validate.IsOneOf(h.SmallCheckType, "icmp", "dns")
 	if err != nil {
-		return fmt.Errorf("health VPN settings: %w", err)
+		return fmt.Errorf("%w: %s", ErrSmallCheckTypeNotValid, err)
 	}
 
 	return nil
@@ -52,12 +70,11 @@ func (h Health) Validate() (err error) {
 
 func (h *Health) copy() (copied Health) {
 	return Health{
-		ServerAddress:     h.ServerAddress,
-		ReadHeaderTimeout: h.ReadHeaderTimeout,
-		ReadTimeout:       h.ReadTimeout,
-		TargetAddress:     h.TargetAddress,
-		SuccessWait:       h.SuccessWait,
-		VPN:               h.VPN.copy(),
+		ServerAddress:   h.ServerAddress,
+		TargetAddresses: h.TargetAddresses,
+		ICMPTargetIPs:   gosettings.CopySlice(h.ICMPTargetIPs),
+		SmallCheckType:  h.SmallCheckType,
+		RestartVPN:      gosettings.CopyPointer(h.RestartVPN),
 	}
 }
 
@@ -66,23 +83,21 @@ func (h *Health) copy() (copied Health) {
 // settings.
 func (h *Health) OverrideWith(other Health) {
 	h.ServerAddress = gosettings.OverrideWithComparable(h.ServerAddress, other.ServerAddress)
-	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.VPN.overrideWith(other.VPN)
+	h.TargetAddresses = gosettings.OverrideWithSlice(h.TargetAddresses, other.TargetAddresses)
+	h.ICMPTargetIPs = gosettings.OverrideWithSlice(h.ICMPTargetIPs, other.ICMPTargetIPs)
+	h.SmallCheckType = gosettings.OverrideWithComparable(h.SmallCheckType, other.SmallCheckType)
+	h.RestartVPN = gosettings.OverrideWithPointer(h.RestartVPN, other.RestartVPN)
 }
 
 func (h *Health) SetDefaults() {
 	h.ServerAddress = gosettings.DefaultComparable(h.ServerAddress, "127.0.0.1:9999")
-	const defaultReadHeaderTimeout = 100 * time.Millisecond
-	h.ReadHeaderTimeout = gosettings.DefaultComparable(h.ReadHeaderTimeout, defaultReadHeaderTimeout)
-	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.SuccessWait = gosettings.DefaultComparable(h.SuccessWait, defaultSuccessWait)
-	h.VPN.setDefaults()
+	h.TargetAddresses = gosettings.DefaultSlice(h.TargetAddresses, []string{"cloudflare.com:443", "github.com:443"})
+	h.ICMPTargetIPs = gosettings.DefaultSlice(h.ICMPTargetIPs, []netip.Addr{
+		netip.AddrFrom4([4]byte{1, 1, 1, 1}),
+		netip.AddrFrom4([4]byte{8, 8, 8, 8}),
+	})
+	h.SmallCheckType = gosettings.DefaultComparable(h.SmallCheckType, "icmp")
+	h.RestartVPN = gosettings.DefaultPointer(h.RestartVPN, true)
 }
 
 func (h Health) String() string {
@@ -92,28 +107,40 @@ func (h Health) String() string {
 func (h Health) toLinesNode() (node *gotree.Node) {
 	node = gotree.New("Health settings:")
 	node.Appendf("Server listening address: %s", h.ServerAddress)
-	node.Appendf("Target address: %s", h.TargetAddress)
-	node.Appendf("Duration to wait after success: %s", h.SuccessWait)
-	node.Appendf("Read header timeout: %s", h.ReadHeaderTimeout)
-	node.Appendf("Read timeout: %s", h.ReadTimeout)
-	node.AppendNode(h.VPN.toLinesNode("VPN"))
+	targetAddrs := node.Appendf("Target addresses:")
+	for _, targetAddr := range h.TargetAddresses {
+		targetAddrs.Append(targetAddr)
+	}
+	switch h.SmallCheckType {
+	case "icmp":
+		icmpNode := node.Appendf("Small health check type: ICMP echo request")
+		if len(h.ICMPTargetIPs) == 1 && h.ICMPTargetIPs[0].IsUnspecified() {
+			icmpNode.Appendf("ICMP target IP: VPN server IP address")
+		} else {
+			icmpIPs := icmpNode.Appendf("ICMP target IPs:")
+			for _, ip := range h.ICMPTargetIPs {
+				icmpIPs.Append(ip.String())
+			}
+		}
+	case "dns":
+		node.Appendf("Small health check type: Plain DNS lookup over UDP")
+	}
+	node.Appendf("Restart VPN on healthcheck failure: %s", gosettings.BoolToYesNo(h.RestartVPN))
 	return node
 }
 
 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.SuccessWait, err = r.Duration("HEALTH_SUCCESS_WAIT_DURATION")
+	h.TargetAddresses = r.CSV("HEALTH_TARGET_ADDRESSES",
+		reader.RetroKeys("HEALTH_ADDRESS_TO_PING", "HEALTH_TARGET_ADDRESS"))
+	h.ICMPTargetIPs, err = r.CSVNetipAddresses("HEALTH_ICMP_TARGET_IPS", reader.RetroKeys("HEALTH_ICMP_TARGET_IP"))
 	if err != nil {
 		return err
 	}
-
-	err = h.VPN.read(r)
+	h.SmallCheckType = r.String("HEALTH_SMALL_CHECK_TYPE")
+	h.RestartVPN, err = r.BoolPtr("HEALTH_RESTART_VPN")
 	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/openvpnselection.go

@@ -2,6 +2,7 @@ package settings
 
 import (
 	"fmt"
+	"net/netip"
 	"strings"
 
 	"github.com/qdm12/gluetun/internal/configuration/settings/helpers"
@@ -24,6 +25,12 @@ type OpenVPNSelection struct {
 	// and can be udp or tcp. It cannot be the empty string
 	// in the internal state.
 	Protocol string `json:"protocol"`
+	// EndpointIP is the server endpoint IP address.
+	// If set, it overrides any IP address from the picked
+	// built-in server connection. To indicate it should
+	// not be used, it should be set to [netip.IPv4Unspecified].
+	// It can never be the zero value in the internal state.
+	EndpointIP netip.Addr `json:"endpoint_ip"`
 	// CustomPort is the OpenVPN server endpoint port.
 	// It can be set to 0 to indicate no custom port should
 	// be used. It cannot be nil in the internal state.
@@ -142,6 +149,7 @@ func (o *OpenVPNSelection) copy() (copied OpenVPNSelection) {
 	return OpenVPNSelection{
 		ConfFile:     gosettings.CopyPointer(o.ConfFile),
 		Protocol:     o.Protocol,
+		EndpointIP:   o.EndpointIP,
 		CustomPort:   gosettings.CopyPointer(o.CustomPort),
 		PIAEncPreset: gosettings.CopyPointer(o.PIAEncPreset),
 	}
@@ -151,12 +159,14 @@ func (o *OpenVPNSelection) overrideWith(other OpenVPNSelection) {
 	o.ConfFile = gosettings.OverrideWithPointer(o.ConfFile, other.ConfFile)
 	o.Protocol = gosettings.OverrideWithComparable(o.Protocol, other.Protocol)
 	o.CustomPort = gosettings.OverrideWithPointer(o.CustomPort, other.CustomPort)
+	o.EndpointIP = gosettings.OverrideWithValidator(o.EndpointIP, other.EndpointIP)
 	o.PIAEncPreset = gosettings.OverrideWithPointer(o.PIAEncPreset, other.PIAEncPreset)
 }
 
 func (o *OpenVPNSelection) setDefaults(vpnProvider string) {
 	o.ConfFile = gosettings.DefaultPointer(o.ConfFile, "")
 	o.Protocol = gosettings.DefaultComparable(o.Protocol, constants.UDP)
+	o.EndpointIP = gosettings.DefaultValidator(o.EndpointIP, netip.IPv4Unspecified())
 	o.CustomPort = gosettings.DefaultPointer(o.CustomPort, 0)
 
 	var defaultEncPreset string
@@ -174,6 +184,10 @@ func (o OpenVPNSelection) toLinesNode() (node *gotree.Node) {
 	node = gotree.New("OpenVPN server selection settings:")
 	node.Appendf("Protocol: %s", strings.ToUpper(o.Protocol))
 
+	if !o.EndpointIP.IsUnspecified() {
+		node.Appendf("Endpoint IP address: %s", o.EndpointIP)
+	}
+
 	if *o.CustomPort != 0 {
 		node.Appendf("Custom port: %d", *o.CustomPort)
 	}
@@ -194,6 +208,12 @@ func (o *OpenVPNSelection) read(r *reader.Reader) (err error) {
 
 	o.Protocol = r.String("OPENVPN_PROTOCOL", reader.RetroKeys("PROTOCOL"))
 
+	o.EndpointIP, err = r.NetipAddr("OPENVPN_ENDPOINT_IP",
+		reader.RetroKeys("OPENVPN_TARGET_IP", "VPN_ENDPOINT_IP"))
+	if err != nil {
+		return err
+	}
+
 	o.CustomPort, err = r.Uint16Ptr("OPENVPN_ENDPOINT_PORT",
 		reader.RetroKeys("PORT", "OPENVPN_PORT", "VPN_ENDPOINT_PORT"))
 	if err != nil {

internal/configuration/settings/portforward.go

@@ -29,6 +29,14 @@ type PortForwarding struct {
 	// to write to a file. It cannot be nil for the
 	// internal state
 	Filepath *string `json:"status_file_path"`
+	// UpCommand is the command to use when the port forwarding is up.
+	// It can be the empty string to indicate not to run a command.
+	// It cannot be nil in the internal state.
+	UpCommand *string `json:"up_command"`
+	// DownCommand is the command to use after the port forwarding goes down.
+	// It can be the empty string to indicate to NOT run a command.
+	// It cannot be nil in the internal state.
+	DownCommand *string `json:"down_command"`
 	// ListeningPort is the port traffic would be redirected to from the
 	// forwarded port. The redirection is disabled if it is set to 0, which
 	// is its default as well.
@@ -84,6 +92,8 @@ func (p *PortForwarding) Copy() (copied PortForwarding) {
 		Enabled:       gosettings.CopyPointer(p.Enabled),
 		Provider:      gosettings.CopyPointer(p.Provider),
 		Filepath:      gosettings.CopyPointer(p.Filepath),
+		UpCommand:     gosettings.CopyPointer(p.UpCommand),
+		DownCommand:   gosettings.CopyPointer(p.DownCommand),
 		ListeningPort: gosettings.CopyPointer(p.ListeningPort),
 		Username:      p.Username,
 		Password:      p.Password,
@@ -94,6 +104,8 @@ func (p *PortForwarding) OverrideWith(other PortForwarding) {
 	p.Enabled = gosettings.OverrideWithPointer(p.Enabled, other.Enabled)
 	p.Provider = gosettings.OverrideWithPointer(p.Provider, other.Provider)
 	p.Filepath = gosettings.OverrideWithPointer(p.Filepath, other.Filepath)
+	p.UpCommand = gosettings.OverrideWithPointer(p.UpCommand, other.UpCommand)
+	p.DownCommand = gosettings.OverrideWithPointer(p.DownCommand, other.DownCommand)
 	p.ListeningPort = gosettings.OverrideWithPointer(p.ListeningPort, other.ListeningPort)
 	p.Username = gosettings.OverrideWithComparable(p.Username, other.Username)
 	p.Password = gosettings.OverrideWithComparable(p.Password, other.Password)
@@ -103,6 +115,8 @@ func (p *PortForwarding) setDefaults() {
 	p.Enabled = gosettings.DefaultPointer(p.Enabled, false)
 	p.Provider = gosettings.DefaultPointer(p.Provider, "")
 	p.Filepath = gosettings.DefaultPointer(p.Filepath, "/tmp/gluetun/forwarded_port")
+	p.UpCommand = gosettings.DefaultPointer(p.UpCommand, "")
+	p.DownCommand = gosettings.DefaultPointer(p.DownCommand, "")
 	p.ListeningPort = gosettings.DefaultPointer(p.ListeningPort, 0)
 }
 
@@ -135,6 +149,13 @@ func (p PortForwarding) toLinesNode() (node *gotree.Node) {
 	}
 	node.Appendf("Forwarded port file path: %s", filepath)
 
+	if *p.UpCommand != "" {
+		node.Appendf("Forwarded port up command: %s", *p.UpCommand)
+	}
+	if *p.DownCommand != "" {
+		node.Appendf("Forwarded port down command: %s", *p.DownCommand)
+	}
+
 	if p.Username != "" {
 		credentialsNode := node.Appendf("Credentials:")
 		credentialsNode.Appendf("Username: %s", p.Username)
@@ -163,6 +184,12 @@ func (p *PortForwarding) read(r *reader.Reader) (err error) {
 			"PRIVATE_INTERNET_ACCESS_VPN_PORT_FORWARDING_STATUS_FILE",
 		))
 
+	p.UpCommand = r.Get("VPN_PORT_FORWARDING_UP_COMMAND",
+		reader.ForceLowercase(false))
+
+	p.DownCommand = r.Get("VPN_PORT_FORWARDING_DOWN_COMMAND",
+		reader.ForceLowercase(false))
+
 	p.ListeningPort, err = r.Uint16Ptr("VPN_PORT_FORWARDING_LISTENING_PORT")
 	if err != nil {
 		return err

internal/configuration/settings/server.go

@@ -1,11 +1,14 @@
 package settings
 
 import (
+	"bytes"
+	"encoding/json"
 	"fmt"
 	"net"
 	"os"
 	"strconv"
 
+	"github.com/qdm12/gluetun/internal/server/middlewares/auth"
 	"github.com/qdm12/gosettings"
 	"github.com/qdm12/gosettings/reader"
 	"github.com/qdm12/gotree"
@@ -24,6 +27,9 @@ type ControlServer struct {
 	// It cannot be empty in the internal state and defaults to
 	// /gluetun/auth/config.toml.
 	AuthFilePath string
+	// AuthDefaultRole is a JSON encoded object defining the default role
+	// that applies to all routes without a previously user-defined role assigned to.
+	AuthDefaultRole string
 }
 
 func (c ControlServer) validate() (err error) {
@@ -44,14 +50,30 @@ func (c ControlServer) validate() (err error) {
 			ErrControlServerPrivilegedPort, port, uid)
 	}
 
+	jsonDecoder := json.NewDecoder(bytes.NewBufferString(c.AuthDefaultRole))
+	jsonDecoder.DisallowUnknownFields()
+	var role auth.Role
+	err = jsonDecoder.Decode(&role)
+	if err != nil {
+		return fmt.Errorf("default authentication role is not valid JSON: %w", err)
+	}
+
+	if role.Auth != "" {
+		err = role.Validate()
+		if err != nil {
+			return fmt.Errorf("default authentication role is not valid: %w", err)
+		}
+	}
+
 	return nil
 }
 
 func (c *ControlServer) copy() (copied ControlServer) {
 	return ControlServer{
-		Address:      gosettings.CopyPointer(c.Address),
-		Log:          gosettings.CopyPointer(c.Log),
-		AuthFilePath: c.AuthFilePath,
+		Address:         gosettings.CopyPointer(c.Address),
+		Log:             gosettings.CopyPointer(c.Log),
+		AuthFilePath:    c.AuthFilePath,
+		AuthDefaultRole: c.AuthDefaultRole,
 	}
 }
 
@@ -62,12 +84,21 @@ func (c *ControlServer) overrideWith(other ControlServer) {
 	c.Address = gosettings.OverrideWithPointer(c.Address, other.Address)
 	c.Log = gosettings.OverrideWithPointer(c.Log, other.Log)
 	c.AuthFilePath = gosettings.OverrideWithComparable(c.AuthFilePath, other.AuthFilePath)
+	c.AuthDefaultRole = gosettings.OverrideWithComparable(c.AuthDefaultRole, other.AuthDefaultRole)
 }
 
 func (c *ControlServer) setDefaults() {
 	c.Address = gosettings.DefaultPointer(c.Address, ":8000")
 	c.Log = gosettings.DefaultPointer(c.Log, true)
 	c.AuthFilePath = gosettings.DefaultComparable(c.AuthFilePath, "/gluetun/auth/config.toml")
+	c.AuthDefaultRole = gosettings.DefaultComparable(c.AuthDefaultRole, "{}")
+	if c.AuthDefaultRole != "{}" {
+		var role auth.Role
+		_ = json.Unmarshal([]byte(c.AuthDefaultRole), &role)
+		role.Name = "default"
+		roleBytes, _ := json.Marshal(role) //nolint:errchkjson
+		c.AuthDefaultRole = string(roleBytes)
+	}
 }
 
 func (c ControlServer) String() string {
@@ -79,6 +110,11 @@ func (c ControlServer) toLinesNode() (node *gotree.Node) {
 	node.Appendf("Listening address: %s", *c.Address)
 	node.Appendf("Logging: %s", gosettings.BoolToYesNo(c.Log))
 	node.Appendf("Authentication file path: %s", c.AuthFilePath)
+	if c.AuthDefaultRole != "{}" {
+		var role auth.Role
+		_ = json.Unmarshal([]byte(c.AuthDefaultRole), &role)
+		node.AppendNode(role.ToLinesNode())
+	}
 	return node
 }
 
@@ -91,6 +127,7 @@ func (c *ControlServer) read(r *reader.Reader) (err error) {
 	c.Address = r.Get("HTTP_CONTROL_SERVER_ADDRESS")
 
 	c.AuthFilePath = r.String("HTTP_CONTROL_SERVER_AUTH_CONFIG_FILEPATH")
+	c.AuthDefaultRole = r.String("HTTP_CONTROL_SERVER_AUTH_DEFAULT_ROLE")
 
 	return nil
 }

internal/configuration/settings/serverselection.go

@@ -3,7 +3,6 @@ package settings
 import (
 	"errors"
 	"fmt"
-	"net/netip"
 	"strings"
 
 	"github.com/qdm12/gluetun/internal/configuration/settings/helpers"
@@ -17,17 +16,11 @@ 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.
 	VPN string `json:"vpn"`
-	// TargetIP is the server endpoint IP address to use.
-	// It will override any IP address from the picked
-	// built-in server. It cannot be the empty value in the internal
-	// state, and can be set to the unspecified address to indicate
-	// there is not target IP address to use.
-	TargetIP netip.Addr `json:"target_ip"`
 	// Countries is the list of countries to filter VPN servers with.
 	Countries []string `json:"countries"`
 	// Categories is the list of categories to filter VPN servers with.
@@ -299,7 +292,6 @@ func validateFeatureFilters(settings ServerSelection, vpnServiceProvider string)
 func (ss *ServerSelection) copy() (copied ServerSelection) {
 	return ServerSelection{
 		VPN:             ss.VPN,
-		TargetIP:        ss.TargetIP,
 		Countries:       gosettings.CopySlice(ss.Countries),
 		Categories:      gosettings.CopySlice(ss.Categories),
 		Regions:         gosettings.CopySlice(ss.Regions),
@@ -323,7 +315,6 @@ func (ss *ServerSelection) copy() (copied ServerSelection) {
 
 func (ss *ServerSelection) overrideWith(other ServerSelection) {
 	ss.VPN = gosettings.OverrideWithComparable(ss.VPN, other.VPN)
-	ss.TargetIP = gosettings.OverrideWithValidator(ss.TargetIP, other.TargetIP)
 	ss.Countries = gosettings.OverrideWithSlice(ss.Countries, other.Countries)
 	ss.Categories = gosettings.OverrideWithSlice(ss.Categories, other.Categories)
 	ss.Regions = gosettings.OverrideWithSlice(ss.Regions, other.Regions)
@@ -346,7 +337,6 @@ func (ss *ServerSelection) overrideWith(other ServerSelection) {
 
 func (ss *ServerSelection) setDefaults(vpnProvider string, portForwardingEnabled bool) {
 	ss.VPN = gosettings.DefaultComparable(ss.VPN, vpn.OpenVPN)
-	ss.TargetIP = gosettings.DefaultValidator(ss.TargetIP, netip.IPv4Unspecified())
 	ss.OwnedOnly = gosettings.DefaultPointer(ss.OwnedOnly, false)
 	ss.FreeOnly = gosettings.DefaultPointer(ss.FreeOnly, false)
 	ss.PremiumOnly = gosettings.DefaultPointer(ss.PremiumOnly, false)
@@ -354,11 +344,8 @@ 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
-	if portForwardingEnabled && helpers.IsOneOf(vpnProvider,
-		providers.PrivateInternetAccess, providers.Protonvpn) {
-		defaultPortForwardOnly = true
-	}
+	defaultPortForwardOnly := portForwardingEnabled &&
+		helpers.IsOneOf(vpnProvider, providers.PrivateInternetAccess, providers.Protonvpn)
 	ss.PortForwardOnly = gosettings.DefaultPointer(ss.PortForwardOnly, defaultPortForwardOnly)
 	ss.OpenVPN.setDefaults(vpnProvider)
 	ss.Wireguard.setDefaults()
@@ -371,9 +358,6 @@ func (ss ServerSelection) String() string {
 func (ss ServerSelection) toLinesNode() (node *gotree.Node) {
 	node = gotree.New("Server selection settings:")
 	node.Appendf("VPN type: %s", ss.VPN)
-	if !ss.TargetIP.IsUnspecified() {
-		node.Appendf("Target IP address: %s", ss.TargetIP)
-	}
 
 	if len(ss.Countries) > 0 {
 		node.Appendf("Countries: %s", strings.Join(ss.Countries, ", "))
@@ -464,12 +448,6 @@ func (ss *ServerSelection) read(r *reader.Reader,
 ) (err error) {
 	ss.VPN = vpnType
 
-	ss.TargetIP, err = r.NetipAddr("OPENVPN_ENDPOINT_IP",
-		reader.RetroKeys("OPENVPN_TARGET_IP", "VPN_ENDPOINT_IP"))
-	if err != nil {
-		return err
-	}
-
 	countriesRetroKeys := []string{"COUNTRY"}
 	if vpnProvider == providers.Cyberghost {
 		countriesRetroKeys = append(countriesRetroKeys, "REGION")

internal/configuration/settings/settings.go

@@ -177,10 +177,10 @@ 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."+
-			" The default value changed to 127.0.0.1 so it uses the internal DoT serves."+
-			" If the DoT server fails to start, the IPv4 address of the first plaintext DNS server"+
-			" corresponding to the first DoT provider chosen is used.")
+			" so the local forwarding DNS server will not be used."+
+			" The default value changed to 127.0.0.1 so it uses the internal DNS server."+
+			" If this server fails to start, the IPv4 address of the first plaintext DNS server"+
+			" corresponding to the first DNS provider chosen is used.")
 	}
 
 	return warnings

internal/configuration/settings/settings_test.go

@@ -40,30 +40,31 @@ 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:
-|       ├── Enabled: yes
-|       ├── Update period: every 24h0m0s
-|       ├── Upstream resolvers:
-|       |   └── Cloudflare
-|       ├── Caching: yes
-|       ├── IPv6: no
-|       └── DNS filtering settings:
-|           ├── Block malicious: yes
-|           ├── Block ads: no
-|           └── Block surveillance: yes
+|   ├── DNS forwarder server enabled: yes
+|   ├── Upstream resolver type: dot
+|   ├── Upstream resolvers:
+|   |   └── Cloudflare
+|   ├── Caching: yes
+|   ├── IPv6: no
+|   ├── Update period: every 24h0m0s
+|   └── DNS filtering settings:
+|       ├── Block malicious: yes
+|       ├── Block ads: no
+|       └── Block surveillance: yes
 ├── Firewall settings:
 |   └── Enabled: yes
 ├── Log settings:
 |   └── Log level: INFO
 ├── Health settings:
 |   ├── Server listening address: 127.0.0.1:9999
-|   ├── Target address: cloudflare.com:443
-|   ├── Duration to wait after success: 5s
-|   ├── Read header timeout: 100ms
-|   ├── Read timeout: 500ms
-|   └── VPN wait durations:
-|       ├── Initial duration: 6s
-|       └── Additional duration: 5s
+|   ├── Target addresses:
+|   |   ├── cloudflare.com:443
+|   |   └── github.com:443
+|   ├── Small health check type: ICMP echo request
+|   |   └── ICMP target IPs:
+|   |       ├── 1.1.1.1
+|   |       └── 8.8.8.8
+|   └── Restart VPN on healthcheck failure: yes
 ├── 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/configuration/settings/updater.go

@@ -2,6 +2,7 @@ package settings
 
 import (
 	"fmt"
+	"slices"
 	"strings"
 	"time"
 
@@ -31,6 +32,10 @@ type Updater struct {
 	// Providers is the list of VPN service providers
 	// to update server information for.
 	Providers []string
+	// ProtonEmail is the email to authenticate with the Proton API.
+	ProtonEmail *string
+	// ProtonPassword is the password to authenticate with the Proton API.
+	ProtonPassword *string
 }
 
 func (u Updater) Validate() (err error) {
@@ -51,6 +56,18 @@ func (u Updater) Validate() (err error) {
 		if err != nil {
 			return fmt.Errorf("%w: %w", ErrVPNProviderNameNotValid, err)
 		}
+
+		if provider == providers.Protonvpn {
+			authenticatedAPI := *u.ProtonEmail != "" || *u.ProtonPassword != ""
+			if authenticatedAPI {
+				switch {
+				case *u.ProtonEmail == "":
+					return fmt.Errorf("%w", ErrUpdaterProtonEmailMissing)
+				case *u.ProtonPassword == "":
+					return fmt.Errorf("%w", ErrUpdaterProtonPasswordMissing)
+				}
+			}
+		}
 	}
 
 	return nil
@@ -58,10 +75,12 @@ func (u Updater) Validate() (err error) {
 
 func (u *Updater) copy() (copied Updater) {
 	return Updater{
-		Period:     gosettings.CopyPointer(u.Period),
-		DNSAddress: u.DNSAddress,
-		MinRatio:   u.MinRatio,
-		Providers:  gosettings.CopySlice(u.Providers),
+		Period:         gosettings.CopyPointer(u.Period),
+		DNSAddress:     u.DNSAddress,
+		MinRatio:       u.MinRatio,
+		Providers:      gosettings.CopySlice(u.Providers),
+		ProtonEmail:    gosettings.CopyPointer(u.ProtonEmail),
+		ProtonPassword: gosettings.CopyPointer(u.ProtonPassword),
 	}
 }
 
@@ -73,6 +92,8 @@ func (u *Updater) overrideWith(other Updater) {
 	u.DNSAddress = gosettings.OverrideWithComparable(u.DNSAddress, other.DNSAddress)
 	u.MinRatio = gosettings.OverrideWithComparable(u.MinRatio, other.MinRatio)
 	u.Providers = gosettings.OverrideWithSlice(u.Providers, other.Providers)
+	u.ProtonEmail = gosettings.OverrideWithPointer(u.ProtonEmail, other.ProtonEmail)
+	u.ProtonPassword = gosettings.OverrideWithPointer(u.ProtonPassword, other.ProtonPassword)
 }
 
 func (u *Updater) SetDefaults(vpnProvider string) {
@@ -87,6 +108,10 @@ func (u *Updater) SetDefaults(vpnProvider string) {
 	if len(u.Providers) == 0 && vpnProvider != providers.Custom {
 		u.Providers = []string{vpnProvider}
 	}
+
+	// Set these to empty strings to avoid nil pointer panics
+	u.ProtonEmail = gosettings.DefaultPointer(u.ProtonEmail, "")
+	u.ProtonPassword = gosettings.DefaultPointer(u.ProtonPassword, "")
 }
 
 func (u Updater) String() string {
@@ -103,6 +128,10 @@ func (u Updater) toLinesNode() (node *gotree.Node) {
 	node.Appendf("DNS address: %s", u.DNSAddress)
 	node.Appendf("Minimum ratio: %.1f", u.MinRatio)
 	node.Appendf("Providers to update: %s", strings.Join(u.Providers, ", "))
+	if slices.Contains(u.Providers, providers.Protonvpn) {
+		node.Appendf("Proton API email: %s", *u.ProtonEmail)
+		node.Appendf("Proton API password: %s", gosettings.ObfuscateKey(*u.ProtonPassword))
+	}
 
 	return node
 }
@@ -125,6 +154,16 @@ func (u *Updater) read(r *reader.Reader) (err error) {
 
 	u.Providers = r.CSV("UPDATER_VPN_SERVICE_PROVIDERS")
 
+	u.ProtonEmail = r.Get("UPDATER_PROTONVPN_EMAIL")
+	if u.ProtonEmail == nil {
+		protonUsername := r.String("UPDATER_PROTONVPN_USERNAME", reader.IsRetro("UPDATER_PROTONVPN_EMAIL"))
+		if protonUsername != "" {
+			protonEmail := protonUsername + "@protonmail.com"
+			u.ProtonEmail = &protonEmail
+		}
+	}
+	u.ProtonPassword = r.Get("UPDATER_PROTONVPN_PASSWORD")
+
 	return nil
 }
 

internal/configuration/settings/wireguardselection.go

@@ -14,11 +14,11 @@ import (
 
 type WireguardSelection struct {
 	// EndpointIP is the server endpoint IP address.
-	// It is only used with VPN providers generating Wireguard
-	// configurations specific to each server and user.
-	// To indicate it should not be used, it should be set
-	// to netip.IPv4Unspecified(). It can never be the zero value
-	// in the internal state.
+	// It is notably required with the custom provider.
+	// Otherwise it overrides any IP address from the picked
+	// built-in server connection. To indicate it should
+	// not be used, it should be set to [netip.IPv4Unspecified].
+	// It can never be the zero value in the internal state.
 	EndpointIP netip.Addr `json:"endpoint_ip"`
 	// EndpointPort is a the server port to use for the VPN server.
 	// It is optional for VPN providers IVPN, Mullvad, Surfshark
@@ -155,7 +155,8 @@ func (w WireguardSelection) toLinesNode() (node *gotree.Node) {
 func (w *WireguardSelection) read(r *reader.Reader) (err error) {
 	w.EndpointIP, err = r.NetipAddr("WIREGUARD_ENDPOINT_IP", reader.RetroKeys("VPN_ENDPOINT_IP"))
 	if err != nil {
-		return err
+		return fmt.Errorf("%w - note this MUST be an IP address, "+
+			"see https://github.com/qdm12/gluetun/issues/788", err)
 	}
 
 	w.EndpointPort, err = r.Uint16Ptr("WIREGUARD_ENDPOINT_PORT", reader.RetroKeys("VPN_ENDPOINT_PORT"))

internal/dns/loop.go

@@ -4,6 +4,7 @@ import (
 	"context"
 	"fmt"
 	"net/http"
+	"net/netip"
 	"time"
 
 	"github.com/qdm12/dns/v2/pkg/middlewares/filter/mapfilter"
@@ -16,22 +17,23 @@ import (
 )
 
 type Loop struct {
-	statusManager *loopstate.State
-	state         *state.State
-	server        *server.Server
-	filter        *mapfilter.Filter
-	resolvConf    string
-	client        *http.Client
-	logger        Logger
-	userTrigger   bool
-	start         <-chan struct{}
-	running       chan<- models.LoopStatus
-	stop          <-chan struct{}
-	stopped       chan<- struct{}
-	updateTicker  <-chan struct{}
-	backoffTime   time.Duration
-	timeNow       func() time.Time
-	timeSince     func(time.Time) time.Duration
+	statusManager  *loopstate.State
+	state          *state.State
+	server         *server.Server
+	filter         *mapfilter.Filter
+	localResolvers []netip.Addr
+	resolvConf     string
+	client         *http.Client
+	logger         Logger
+	userTrigger    bool
+	start          <-chan struct{}
+	running        chan<- models.LoopStatus
+	stop           <-chan struct{}
+	stopped        chan<- struct{}
+	updateTicker   <-chan struct{}
+	backoffTime    time.Duration
+	timeNow        func() time.Time
+	timeSince      func(time.Time) time.Duration
 }
 
 const defaultBackoffTime = 10 * time.Second
@@ -48,7 +50,9 @@ func NewLoop(settings settings.DNS,
 	statusManager := loopstate.New(constants.Stopped, start, running, stop, stopped)
 	state := state.New(statusManager, settings, updateTicker)
 
-	filter, err := mapfilter.New(mapfilter.Settings{})
+	filter, err := mapfilter.New(mapfilter.Settings{
+		Logger: buildFilterLogger(logger),
+	})
 	if err != nil {
 		return nil, fmt.Errorf("creating map filter: %w", err)
 	}
@@ -100,3 +104,15 @@ func (l *Loop) signalOrSetStatus(status models.LoopStatus) {
 		l.statusManager.SetStatus(status)
 	}
 }
+
+type filterLogger struct {
+	logger Logger
+}
+
+func (l *filterLogger) Log(msg string) {
+	l.logger.Info(msg)
+}
+
+func buildFilterLogger(logger Logger) *filterLogger {
+	return &filterLogger{logger: logger}
+}

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
-	// 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()
-	}
+	targetIP := settings.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,
-		Timeout: dialTimeout,
+		AddrPort: netip.AddrPortFrom(targetIP, defaultDNSPort),
+		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

@@ -4,12 +4,20 @@ import (
 	"context"
 	"errors"
 
+	"github.com/qdm12/dns/v2/pkg/nameserver"
 	"github.com/qdm12/gluetun/internal/constants"
 )
 
 func (l *Loop) Run(ctx context.Context, done chan<- struct{}) {
 	defer close(done)
 
+	var err error
+	l.localResolvers, err = nameserver.GetPrivateDNSServers()
+	if err != nil {
+		l.logger.Error("getting private DNS servers: " + err.Error())
+		return
+	}
+
 	if *l.GetSettings().KeepNameserver {
 		l.logger.Warn("⚠️⚠️⚠️  keeping the default container nameservers, " +
 			"this will likely leak DNS traffic outside the VPN " +
@@ -26,18 +34,17 @@ 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 {
 				l.backoffTime = defaultBackoffTime
 				l.logger.Info("ready")
-				l.signalOrSetStatus(constants.Running)
 				break
 			}
 
@@ -54,9 +61,10 @@ func (l *Loop) Run(ctx context.Context, done chan<- struct{}) {
 			l.logAndWait(ctx, err)
 			settings = l.GetSettings()
 		}
+		l.signalOrSetStatus(constants.Running)
 
 		settings = l.GetSettings()
-		if !*settings.KeepNameserver && !*settings.DoT.Enabled {
+		if !*settings.KeepNameserver && !*settings.ServerEnabled {
 			const fallback = false
 			l.useUnencryptedDNS(fallback)
 		}
@@ -74,15 +82,19 @@ func (l *Loop) runWait(ctx context.Context, runError <-chan error) (exitLoop boo
 	for {
 		select {
 		case <-ctx.Done():
-			l.stopServer()
-			// TODO revert OS and Go nameserver when exiting
+			if !*l.GetSettings().KeepNameserver {
+				l.stopServer()
+				// TODO revert OS and Go nameserver when exiting
+			}
 			return true
 		case <-l.stop:
 			l.userTrigger = true
 			l.logger.Info("stopping")
-			const fallback = false
-			l.useUnencryptedDNS(fallback)
-			l.stopServer()
+			if !*l.GetSettings().KeepNameserver {
+				const fallback = false
+				l.useUnencryptedDNS(fallback)
+				l.stopServer()
+			}
 			l.stopped <- struct{}{}
 		case <-l.start:
 			l.userTrigger = true
@@ -101,6 +113,6 @@ 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

@@ -3,12 +3,16 @@ package dns
 import (
 	"context"
 	"fmt"
+	"net/netip"
 
+	"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/middlewares/localdns"
+	"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 +26,63 @@ func (l *Loop) SetSettings(ctx context.Context, settings settings.DNS) (
 	return l.state.SetSettings(ctx, settings)
 }
 
-func buildDoTSettings(settings settings.DNS,
-	filter *mapfilter.Filter, logger Logger) (
+func buildServerSettings(settings settings.DNS,
+	filter *mapfilter.Filter, localResolvers []netip.Addr,
+	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))
-	for i := range settings.DoT.Providers {
+	upstreamResolvers := make([]provider.Provider, len(settings.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 {
-		dotSettings.IPVersion = "ipv6"
+
+	ipVersion := "ipv4"
+	if *settings.IPv6 {
+		ipVersion = "ipv6"
 	}
 
-	serverSettings.Dialer, err = dot.New(dotSettings)
-	if err != nil {
-		return server.Settings{}, fmt.Errorf("creating DNS over TLS dialer: %w", err)
+	var dialer server.Dialer
+	switch settings.UpstreamType {
+	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)
@@ -70,5 +104,22 @@ func buildDoTSettings(settings settings.DNS,
 	}
 	serverSettings.Middlewares = append(serverSettings.Middlewares, filterMiddleware)
 
+	localResolversAddrPorts := make([]netip.AddrPort, len(localResolvers))
+	const defaultDNSPort = 53
+	for i, addr := range localResolvers {
+		localResolversAddrPorts[i] = netip.AddrPortFrom(addr, defaultDNSPort)
+	}
+	localDNSMiddleware, err := localdns.New(localdns.Settings{
+		Resolvers: localResolversAddrPorts, // auto-detected at container start only
+		Logger:    logger,
+	})
+	if err != nil {
+		return server.Settings{}, fmt.Errorf("creating local DNS middleware: %w", err)
+	}
+	// Place after cache middleware, since we want to avoid caching for local
+	// hostnames that may change regularly.
+	// Place after filter middleware to avoid conflicts with the rebinding protection.
+	serverSettings.Middlewares = append(serverSettings.Middlewares, localDNSMiddleware)
+
 	return serverSettings, nil
 }

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.localResolvers, 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 {
@@ -37,6 +37,7 @@ func (l *Loop) updateFiles(ctx context.Context) (err error) {
 		IPPrefixes: result.BlockedIPPrefixes,
 	}
 	updateSettings.BlockHostnames(result.BlockedHostnames)
+	updateSettings.SetRebindingProtectionExempt(settings.Blacklist.RebindingProtectionExemptHostnames)
 	err = l.filter.Update(updateSettings)
 	if err != nil {
 		return fmt.Errorf("updating filter: %w", err)

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,

internal/firewall/list.go

@@ -22,7 +22,7 @@ type chainRule struct {
 	packets         uint64
 	bytes           uint64
 	target          string       // "ACCEPT", "DROP", "REJECT" or "REDIRECT"
-	protocol        string       // "tcp", "udp" or "" for all protocols.
+	protocol        string       // "icmp", "tcp", "udp" or "" for all protocols.
 	inputInterface  string       // input interface, for example "tun0" or "*""
 	outputInterface string       // output interface, for example "eth0" or "*""
 	source          netip.Prefix // source IP CIDR, for example 0.0.0.0/0. Must be valid.
@@ -323,10 +323,12 @@ var ErrProtocolUnknown = errors.New("unknown protocol")
 
 func parseProtocol(s string) (protocol string, err error) {
 	switch s {
-	case "0":
-	case "6":
+	case "0", "all":
+	case "1", "icmp":
+		protocol = "icmp"
+	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

@@ -56,7 +56,9 @@ num pkts bytes target     prot opt in     out     source               destinati
 num pkts bytes target     prot opt in     out     source               destination
 1   0     0 ACCEPT     17   --  tun0   *       0.0.0.0/0            0.0.0.0/0            udp dpt:55405
 2   0     0 ACCEPT     6    --  tun0   *       0.0.0.0/0            0.0.0.0/0            tcp dpt:55405
-3   0     0 DROP       0    --  tun0   *       1.2.3.4              0.0.0.0/0
+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",
@@ -92,6 +94,17 @@ num pkts bytes target     prot opt in     out     source               destinati
 						lineNumber:      3,
 						packets:         0,
 						bytes:           0,
+						target:          "ACCEPT",
+						protocol:        "icmp",
+						inputInterface:  "tun0",
+						outputInterface: "*",
+						source:          netip.MustParsePrefix("0.0.0.0/0"),
+						destination:     netip.MustParsePrefix("0.0.0.0/0"),
+					},
+					{
+						lineNumber:      4,
+						packets:         0,
+						bytes:           0,
 						target:          "DROP",
 						protocol:        "",
 						inputInterface:  "tun0",
@@ -99,6 +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/firewall/support.go

@@ -92,7 +92,7 @@ func testIptablesPath(ctx context.Context, path string,
 	// Set policy as the existing policy so no mutation is done.
 	// This is an extra check for some buggy kernels where setting the policy
 	// does not work.
-	cmd = exec.CommandContext(ctx, path, "-L", "INPUT")
+	cmd = exec.CommandContext(ctx, path, "-nL", "INPUT")
 	output, err = runner.Run(cmd)
 	if err != nil {
 		unsupportedMessage = fmt.Sprintf("%s (%s)", output, err)

internal/firewall/support_test.go

@@ -24,7 +24,7 @@ func newDeleteTestRuleMatcher(path string) *cmdMatcher {
 
 func newListInputRulesMatcher(path string) *cmdMatcher {
 	return newCmdMatcher(path,
-		"^-L$", "^INPUT$")
+		"^-nL$", "^INPUT$")
 }
 
 func newSetPolicyMatcher(path, inputPolicy string) *cmdMatcher { //nolint:unparam

internal/healthcheck/checker.go

@@ -0,0 +1,326 @@
+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 {
+	tlsDialAddrs   []string
+	dialer         *net.Dialer
+	echoer         *icmp.Echoer
+	dnsClient      *dns.Client
+	logger         Logger
+	icmpTargetIPs  []netip.Addr
+	smallCheckType string
+	configMutex    sync.Mutex
+
+	icmpNotPermitted bool
+
+	// 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 addresses, the ICMP echo IP address
+// to target and the desired small check type (dns or icmp).
+// This function MUST be called before calling [Checker.Start].
+func (c *Checker) SetConfig(tlsDialAddrs []string, icmpTargets []netip.Addr,
+	smallCheckType string,
+) {
+	c.configMutex.Lock()
+	defer c.configMutex.Unlock()
+	c.tlsDialAddrs = tlsDialAddrs
+	c.icmpTargetIPs = icmpTargets
+	c.smallCheckType = smallCheckType
+}
+
+// Start starts the checker by first running a blocking 6s-timed TCP+TLS check,
+// and, on success, starts the periodic checks in a separate goroutine:
+// - a "small" ICMP echo check every minute
+// - 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 len(c.tlsDialAddrs) == 0 || len(c.icmpTargetIPs) == 0 || c.smallCheckType == "" {
+		panic("call Checker.SetConfig with non empty values before Checker.Start")
+	}
+
+	if c.icmpNotPermitted {
+		// restore forced check type to dns if icmp was found to be not permitted
+		c.smallCheckType = smallCheckDNS
+	}
+
+	err = c.startupCheck(ctx)
+	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
+	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.tlsDialAddrs = nil
+	c.icmpTargetIPs = nil
+	c.smallCheckType = ""
+	return nil
+}
+
+func (c *Checker) smallPeriodicCheck(ctx context.Context) error {
+	c.configMutex.Lock()
+	icmpTargetIPs := make([]netip.Addr, len(c.icmpTargetIPs))
+	copy(icmpTargetIPs, c.icmpTargetIPs)
+	c.configMutex.Unlock()
+	tryTimeouts := []time.Duration{
+		5 * time.Second,
+		5 * time.Second,
+		5 * time.Second,
+		10 * time.Second,
+		10 * time.Second,
+		10 * time.Second,
+		15 * time.Second,
+		15 * time.Second,
+		15 * time.Second,
+		30 * time.Second,
+	}
+	check := func(ctx context.Context, try int) error {
+		if c.smallCheckType == smallCheckDNS {
+			return c.dnsClient.Check(ctx)
+		}
+		ip := icmpTargetIPs[try%len(icmpTargetIPs)]
+		err := c.echoer.Echo(ctx, ip)
+		if errors.Is(err, icmp.ErrNotPermitted) {
+			c.icmpNotPermitted = true
+			c.smallCheckType = smallCheckDNS
+			c.logger.Infof("%s; permanently falling back to %s checks",
+				smallCheckTypeToString(c.smallCheckType), err)
+			return c.dnsClient.Check(ctx)
+		}
+		return err
+	}
+	return withRetries(ctx, tryTimeouts, c.logger, smallCheckTypeToString(c.smallCheckType), check)
+}
+
+func (c *Checker) fullPeriodicCheck(ctx context.Context) error {
+	// 20s timeout in case the connection is under stress
+	// See https://github.com/qdm12/gluetun/issues/2270
+	tryTimeouts := []time.Duration{10 * time.Second, 15 * time.Second, 30 * time.Second}
+	check := func(ctx context.Context, try int) error {
+		tlsDialAddr := c.tlsDialAddrs[try%len(c.tlsDialAddrs)]
+		return tcpTLSCheck(ctx, c.dialer, tlsDialAddr)
+	}
+	return withRetries(ctx, tryTimeouts, 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, tryTimeouts []time.Duration,
+	logger Logger, checkName string, check func(ctx context.Context, try int) error,
+) error {
+	maxTries := len(tryTimeouts)
+	type errData struct {
+		err        error
+		durationMS int64
+	}
+	errs := make([]errData, maxTries)
+	for i, timeout := range tryTimeouts {
+		start := time.Now()
+		checkCtx, cancel := context.WithTimeout(ctx, timeout)
+		err := check(checkCtx, i)
+		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, i+1, maxTries, err)
+		errs[i].err = err
+		errs[i].durationMS = time.Since(start).Round(time.Millisecond).Milliseconds()
+	}
+
+	errStrings := make([]string, len(errs))
+	for i, err := range errs {
+		errStrings[i] = fmt.Sprintf("attempt %d (%dms): %s", i+1, err.durationMS, err.err)
+	}
+	return fmt.Errorf("%w: %s", ErrAllCheckTriesFailed, strings.Join(errStrings, ", "))
+}
+
+func (c *Checker) startupCheck(ctx context.Context) error {
+	// 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. However, since the addresses to dial
+	// may be multiple, we run the check in parallel. If any succeeds, the check passes.
+	// This is to prevent false negatives at startup, if one of the addresses is down
+	// for external reasons.
+	const timeout = 6 * time.Second
+	ctx, cancel := context.WithTimeout(ctx, timeout)
+	defer cancel()
+	errCh := make(chan error)
+
+	for _, address := range c.tlsDialAddrs {
+		go func(addr string) {
+			err := tcpTLSCheck(ctx, c.dialer, addr)
+			errCh <- err
+		}(address)
+	}
+
+	errs := make([]error, 0, len(c.tlsDialAddrs))
+	success := false
+	for range c.tlsDialAddrs {
+		err := <-errCh
+		if err == nil {
+			success = true
+			cancel()
+			continue
+		} else if success {
+			continue // ignore canceled errors after success
+		}
+
+		c.logger.Debugf("startup check parallel attempt failed: %s", err)
+		errs = append(errs, err)
+	}
+	if success {
+		return nil
+	}
+
+	errStrings := make([]string, len(errs))
+	for i, err := range errs {
+		errStrings[i] = fmt.Sprintf("parallel attempt %d/%d failed: %s", i+1, len(errs), err)
+	}
+	return fmt.Errorf("%w: %s", ErrAllCheckTriesFailed, strings.Join(errStrings, ", "))
+}
+
+const (
+	smallCheckDNS  = "dns"
+	smallCheckICMP = "icmp"
+)
+
+func smallCheckTypeToString(smallCheckType string) string {
+	switch smallCheckType {
+	case smallCheckICMP:
+		return "ICMP echo"
+	case smallCheckDNS:
+		return "plain DNS over UDP"
+	default:
+		panic("unknown small check type: " + smallCheckType)
+	}
+}

internal/healthcheck/checker_test.go

@@ -7,40 +7,41 @@ 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) {
 		t.Parallel()
 
 		dialer := &net.Dialer{}
-		const address = "cloudflare.com:443"
+		addresses := []string{"badaddress:9876", "cloudflare.com:443", "google.com:443"}
 
-		server := &Server{
-			dialer: dialer,
-			config: settings.Health{
-				TargetAddress: address,
-			},
+		checker := &Checker{
+			dialer:       dialer,
+			tlsDialAddrs: addresses,
 		}
 
 		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{
-			dialer: dialer,
-			config: settings.Health{
-				TargetAddress: listeningAddress.String(),
-			},
+		checker := &Checker{
+			dialer:       dialer,
+			tlsDialAddrs: []string{listeningAddress.String()},
 		}
 
-		const timeout = 100 * time.Millisecond
-		ctx, cancel := context.WithTimeout(context.Background(), timeout)
-		defer cancel()
-
-		err = server.healthCheck(ctx)
+		err = checker.fullPeriodicCheck(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].String()
+	resolver := &net.Resolver{
+		PreferGo: true,
+		Dial: func(ctx context.Context, _, _ string) (net.Conn, error) {
+			dialer := net.Dialer{}
+			return dialer.DialContext(ctx, "udp", dnsAddr)
+		},
+	}
+	ips, err := resolver.LookupIP(ctx, "ip", "github.com")
+	switch {
+	case err != nil:
+		c.dnsIPIndex = (c.dnsIPIndex + 1) % len(c.serverAddrs)
+		return fmt.Errorf("with DNS server %s: %w", dnsAddr, err)
+	case len(ips) == 0:
+		c.dnsIPIndex = (c.dnsIPIndex + 1) % len(c.serverAddrs)
+		return fmt.Errorf("with DNS server %s: %w", dnsAddr, 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 to %s: %w", ip, 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 from %s", ErrTimedOut, ip)
+		}
+		return fmt.Errorf("receiving ICMP echo reply from %s: %w", ip, err)
+	}
+
+	sentData := message.Body.(*icmp.Echo).Data //nolint:forcetypeassert
+	if !bytes.Equal(receivedData, sentData) {
+		return fmt.Errorf("%w: sent %x to %s and received %x", ErrICMPEchoDataMismatch, sentData, ip, 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

@@ -10,14 +10,13 @@ import (
 func (s *Server) Run(ctx context.Context, done chan<- struct{}) {
 	defer close(done)
 
-	loopDone := make(chan struct{})
-	go s.runHealthcheckLoop(ctx, loopDone)
-
+	const readHeaderTimeout = 100 * time.Millisecond
+	const readTimeout = 500 * time.Millisecond
 	server := http.Server{
 		Addr:              s.config.ServerAddress,
 		Handler:           s.handler,
-		ReadHeaderTimeout: s.config.ReadHeaderTimeout,
-		ReadTimeout:       s.config.ReadTimeout,
+		ReadHeaderTimeout: readHeaderTimeout,
+		ReadTimeout:       readTimeout,
 	}
 	serverDone := make(chan struct{})
 	go func() {
@@ -37,6 +36,5 @@ 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,
-	logger Logger, vpnLoop StatusApplier,
-) *Server {
+func NewServer(config settings.Health, logger Logger) *Server {
 	return &Server{
 		logger:  logger,
-		handler: newHandler(),
-		dialer: &net.Dialer{
-			Resolver: &net.Resolver{
-				PreferGo: true,
-			},
-		},
-		config: config,
-		vpn: vpnHealth{
-			loop:        vpnLoop,
-			healthyWait: *config.VPN.Initial,
-		},
+		handler: newHandler(logger),
+		config:  config,
 	}
 }
 
+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/natpmp/externaladdress_test.go

@@ -2,6 +2,7 @@ package natpmp
 
 import (
 	"context"
+	"net"
 	"net/netip"
 	"testing"
 	"time"
@@ -23,14 +24,15 @@ func Test_Client_ExternalAddress(t *testing.T) {
 		durationSinceStartOfEpoch time.Duration
 		externalIPv4Address       netip.Addr
 		err                       error
-		errMessage                string
+		errMessageRegex           string
 	}{
 		"failure": {
 			ctx:                 canceledCtx,
 			gateway:             netip.AddrFrom4([4]byte{127, 0, 0, 1}),
 			initialConnDuration: initialConnectionDuration,
-			err:                 context.Canceled,
-			errMessage:          "executing remote procedure call: reading from udp connection: context canceled",
+			err:                 net.ErrClosed,
+			errMessageRegex: "executing remote procedure call: setting connection deadline: " +
+				"set udp 127.0.0.1:[1-9][0-9]{1,4}: use of closed network connection",
 		},
 		"success": {
 			ctx:                 context.Background(),
@@ -60,7 +62,7 @@ func Test_Client_ExternalAddress(t *testing.T) {
 			durationSinceStartOfEpoch, externalIPv4Address, err := client.ExternalAddress(testCase.ctx, testCase.gateway)
 			assert.ErrorIs(t, err, testCase.err)
 			if testCase.err != nil {
-				assert.EqualError(t, err, testCase.errMessage)
+				assert.Regexp(t, testCase.errMessageRegex, err.Error())
 			}
 			assert.Equal(t, testCase.durationSinceStartOfEpoch, durationSinceStartOfEpoch)
 			assert.Equal(t, testCase.externalIPv4Address, externalIPv4Address)

internal/natpmp/rpc.go

@@ -45,8 +45,10 @@ func (c *Client) rpc(ctx context.Context, gateway netip.Addr,
 		cancel()
 		<-endGoroutineDone
 	}()
+	ctxListeningReady := make(chan struct{})
 	go func() {
 		defer close(endGoroutineDone)
+		close(ctxListeningReady)
 		// Context is canceled either by the parent context or
 		// when this function returns.
 		<-ctx.Done()
@@ -60,6 +62,7 @@ func (c *Client) rpc(ctx context.Context, gateway netip.Addr,
 		}
 		err = fmt.Errorf("%w; closing connection: %w", err, closeErr)
 	}()
+	<-ctxListeningReady // really to make unit testing reliable
 
 	const maxResponseSize = 16
 	response = make([]byte, maxResponseSize)

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/portforward/interfaces.go

@@ -3,6 +3,7 @@ package portforward
 import (
 	"context"
 	"net/netip"
+	"os/exec"
 )
 
 type Service interface {
@@ -29,3 +30,8 @@ type Logger interface {
 	Warn(s string)
 	Error(s string)
 }
+
+type Cmder interface {
+	Start(cmd *exec.Cmd) (stdoutLines, stderrLines <-chan string,
+		waitError <-chan error, startErr error)
+}

internal/portforward/loop.go

@@ -20,6 +20,7 @@ type Loop struct {
 	client      *http.Client
 	portAllower PortAllower
 	logger      Logger
+	cmder       Cmder
 	// Fixed parameters
 	uid, gid int
 	// Internal channels and locks
@@ -34,7 +35,7 @@ type Loop struct {
 
 func NewLoop(settings settings.PortForwarding, routing Routing,
 	client *http.Client, portAllower PortAllower,
-	logger Logger, uid, gid int,
+	logger Logger, cmder Cmder, uid, gid int,
 ) *Loop {
 	return &Loop{
 		settings: Settings{
@@ -42,6 +43,8 @@ func NewLoop(settings settings.PortForwarding, routing Routing,
 			Service: service.Settings{
 				Enabled:       settings.Enabled,
 				Filepath:      *settings.Filepath,
+				UpCommand:     *settings.UpCommand,
+				DownCommand:   *settings.DownCommand,
 				ListeningPort: *settings.ListeningPort,
 			},
 		},
@@ -49,6 +52,7 @@ func NewLoop(settings settings.PortForwarding, routing Routing,
 		client:      client,
 		portAllower: portAllower,
 		logger:      logger,
+		cmder:       cmder,
 		uid:         uid,
 		gid:         gid,
 	}
@@ -115,7 +119,7 @@ func (l *Loop) run(runCtx context.Context, runDone chan<- struct{},
 		*serviceSettings.Enabled = *serviceSettings.Enabled && *l.settings.VPNIsUp
 
 		l.service = service.New(serviceSettings, l.routing, l.client,
-			l.portAllower, l.logger, l.uid, l.gid)
+			l.portAllower, l.logger, l.cmder, l.uid, l.gid)
 
 		var err error
 		serviceRunError, err = l.service.Start(runCtx)

internal/portforward/service/command.go

@@ -0,0 +1,61 @@
+package service
+
+import (
+	"context"
+	"fmt"
+	"os/exec"
+	"strings"
+
+	"github.com/qdm12/gluetun/internal/command"
+)
+
+func runCommand(ctx context.Context, cmder Cmder, logger Logger,
+	commandTemplate string, ports []uint16, vpnInterface string,
+) (err error) {
+	portStrings := make([]string, len(ports))
+	for i, port := range ports {
+		portStrings[i] = fmt.Sprint(int(port))
+	}
+	portsString := strings.Join(portStrings, ",")
+	commandString := strings.ReplaceAll(commandTemplate, "{{PORTS}}", portsString)
+	commandString = strings.ReplaceAll(commandString, "{{PORT}}", portStrings[0])
+	commandString = strings.ReplaceAll(commandString, "{{VPN_INTERFACE}}", vpnInterface)
+	args, err := command.Split(commandString)
+	if err != nil {
+		return fmt.Errorf("parsing command: %w", err)
+	}
+
+	cmd := exec.CommandContext(ctx, args[0], args[1:]...) // #nosec G204
+	stdout, stderr, waitError, err := cmder.Start(cmd)
+	if err != nil {
+		return err
+	}
+
+	streamCtx, streamCancel := context.WithCancel(context.Background())
+	streamDone := make(chan struct{})
+	go streamLines(streamCtx, streamDone, logger, stdout, stderr)
+
+	err = <-waitError
+	streamCancel()
+	<-streamDone
+	return err
+}
+
+func streamLines(ctx context.Context, done chan<- struct{},
+	logger Logger, stdout, stderr <-chan string,
+) {
+	defer close(done)
+
+	var line string
+
+	for {
+		select {
+		case <-ctx.Done():
+			return
+		case line = <-stdout:
+			logger.Info(line)
+		case line = <-stderr:
+			logger.Error(line)
+		}
+	}
+}

internal/portforward/service/command_test.go

@@ -0,0 +1,29 @@
+//go:build linux
+
+package service
+
+import (
+	"context"
+	"testing"
+
+	gomock "github.com/golang/mock/gomock"
+	"github.com/qdm12/gluetun/internal/command"
+	"github.com/stretchr/testify/require"
+)
+
+func Test_Service_runCommand(t *testing.T) {
+	t.Parallel()
+	ctrl := gomock.NewController(t)
+
+	ctx := context.Background()
+	cmder := command.New()
+	const commandTemplate = `/bin/sh -c "echo {{PORTS}}-{{PORT}}-{{VPN_INTERFACE}}"`
+	ports := []uint16{1234, 5678}
+	const vpnInterface = "tun0"
+	logger := NewMockLogger(ctrl)
+	logger.EXPECT().Info("1234,5678-1234-tun0")
+
+	err := runCommand(ctx, cmder, logger, commandTemplate, ports, vpnInterface)
+
+	require.NoError(t, err)
+}

internal/portforward/service/fs.go

@@ -14,7 +14,11 @@ func (s *Service) writePortForwardedFile(ports []uint16) (err error) {
 	fileData := []byte(strings.Join(portStrings, "\n"))
 
 	filepath := s.settings.Filepath
-	s.logger.Info("writing port file " + filepath)
+	if len(ports) == 0 {
+		s.logger.Info("clearing port file " + filepath)
+	} else {
+		s.logger.Info("writing port file " + filepath)
+	}
 	const perms = os.FileMode(0o644)
 	err = os.WriteFile(filepath, fileData, perms)
 	if err != nil {

internal/portforward/service/interfaces.go

@@ -3,6 +3,7 @@ package service
 import (
 	"context"
 	"net/netip"
+	"os/exec"
 
 	"github.com/qdm12/gluetun/internal/provider/utils"
 )
@@ -32,3 +33,8 @@ type PortForwarder interface {
 		ports []uint16, err error)
 	KeepPortForward(ctx context.Context, objects utils.PortForwardObjects) (err error)
 }
+
+type Cmder interface {
+	Start(cmd *exec.Cmd) (stdoutLines, stderrLines <-chan string,
+		waitError <-chan error, startErr error)
+}

internal/portforward/service/mocks_generate_test.go

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

internal/portforward/service/mocks_test.go

@@ -0,0 +1,82 @@
+// Code generated by MockGen. DO NOT EDIT.
+// Source: github.com/qdm12/gluetun/internal/portforward/service (interfaces: Logger)
+
+// Package service is a generated GoMock package.
+package service
+
+import (
+	reflect "reflect"
+
+	gomock "github.com/golang/mock/gomock"
+)
+
+// MockLogger is a mock of Logger interface.
+type MockLogger struct {
+	ctrl     *gomock.Controller
+	recorder *MockLoggerMockRecorder
+}
+
+// MockLoggerMockRecorder is the mock recorder for MockLogger.
+type MockLoggerMockRecorder struct {
+	mock *MockLogger
+}
+
+// NewMockLogger creates a new mock instance.
+func NewMockLogger(ctrl *gomock.Controller) *MockLogger {
+	mock := &MockLogger{ctrl: ctrl}
+	mock.recorder = &MockLoggerMockRecorder{mock}
+	return mock
+}
+
+// EXPECT returns an object that allows the caller to indicate expected use.
+func (m *MockLogger) EXPECT() *MockLoggerMockRecorder {
+	return m.recorder
+}
+
+// Debug mocks base method.
+func (m *MockLogger) Debug(arg0 string) {
+	m.ctrl.T.Helper()
+	m.ctrl.Call(m, "Debug", arg0)
+}
+
+// Debug indicates an expected call of Debug.
+func (mr *MockLoggerMockRecorder) Debug(arg0 interface{}) *gomock.Call {
+	mr.mock.ctrl.T.Helper()
+	return mr.mock.ctrl.RecordCallWithMethodType(mr.mock, "Debug", reflect.TypeOf((*MockLogger)(nil).Debug), arg0)
+}
+
+// Error mocks base method.
+func (m *MockLogger) Error(arg0 string) {
+	m.ctrl.T.Helper()
+	m.ctrl.Call(m, "Error", arg0)
+}
+
+// Error indicates an expected call of Error.
+func (mr *MockLoggerMockRecorder) Error(arg0 interface{}) *gomock.Call {
+	mr.mock.ctrl.T.Helper()
+	return mr.mock.ctrl.RecordCallWithMethodType(mr.mock, "Error", reflect.TypeOf((*MockLogger)(nil).Error), arg0)
+}
+
+// Info mocks base method.
+func (m *MockLogger) Info(arg0 string) {
+	m.ctrl.T.Helper()
+	m.ctrl.Call(m, "Info", arg0)
+}
+
+// Info indicates an expected call of Info.
+func (mr *MockLoggerMockRecorder) Info(arg0 interface{}) *gomock.Call {
+	mr.mock.ctrl.T.Helper()
+	return mr.mock.ctrl.RecordCallWithMethodType(mr.mock, "Info", reflect.TypeOf((*MockLogger)(nil).Info), arg0)
+}
+
+// Warn mocks base method.
+func (m *MockLogger) Warn(arg0 string) {
+	m.ctrl.T.Helper()
+	m.ctrl.Call(m, "Warn", arg0)
+}
+
+// Warn indicates an expected call of Warn.
+func (mr *MockLoggerMockRecorder) Warn(arg0 interface{}) *gomock.Call {
+	mr.mock.ctrl.T.Helper()
+	return mr.mock.ctrl.RecordCallWithMethodType(mr.mock, "Warn", reflect.TypeOf((*MockLogger)(nil).Warn), arg0)
+}

internal/portforward/service/service.go

@@ -19,6 +19,7 @@ type Service struct {
 	client      *http.Client
 	portAllower PortAllower
 	logger      Logger
+	cmder       Cmder
 	// Internal channels and locks
 	startStopMutex sync.Mutex
 	keepPortCancel context.CancelFunc
@@ -26,7 +27,7 @@ type Service struct {
 }
 
 func New(settings Settings, routing Routing, client *http.Client,
-	portAllower PortAllower, logger Logger, puid, pgid int,
+	portAllower PortAllower, logger Logger, cmder Cmder, puid, pgid int,
 ) *Service {
 	return &Service{
 		// Fixed parameters
@@ -38,6 +39,7 @@ func New(settings Settings, routing Routing, client *http.Client,
 		client:      client,
 		portAllower: portAllower,
 		logger:      logger,
+		cmder:       cmder,
 	}
 }
 

internal/portforward/service/settings.go

@@ -12,6 +12,8 @@ type Settings struct {
 	Enabled        *bool
 	PortForwarder  PortForwarder
 	Filepath       string
+	UpCommand      string
+	DownCommand    string
 	Interface      string // needed for PIA, PrivateVPN and ProtonVPN, tun0 for example
 	ServerName     string // needed for PIA
 	CanPortForward bool   // needed for PIA
@@ -24,6 +26,8 @@ func (s Settings) Copy() (copied Settings) {
 	copied.Enabled = gosettings.CopyPointer(s.Enabled)
 	copied.PortForwarder = s.PortForwarder
 	copied.Filepath = s.Filepath
+	copied.UpCommand = s.UpCommand
+	copied.DownCommand = s.DownCommand
 	copied.Interface = s.Interface
 	copied.ServerName = s.ServerName
 	copied.CanPortForward = s.CanPortForward
@@ -37,6 +41,8 @@ func (s *Settings) OverrideWith(update Settings) {
 	s.Enabled = gosettings.OverrideWithPointer(s.Enabled, update.Enabled)
 	s.PortForwarder = gosettings.OverrideWithComparable(s.PortForwarder, update.PortForwarder)
 	s.Filepath = gosettings.OverrideWithComparable(s.Filepath, update.Filepath)
+	s.UpCommand = gosettings.OverrideWithComparable(s.UpCommand, update.UpCommand)
+	s.DownCommand = gosettings.OverrideWithComparable(s.DownCommand, update.DownCommand)
 	s.Interface = gosettings.OverrideWithComparable(s.Interface, update.Interface)
 	s.ServerName = gosettings.OverrideWithComparable(s.ServerName, update.ServerName)
 	s.CanPortForward = gosettings.OverrideWithComparable(s.CanPortForward, update.CanPortForward)

internal/portforward/service/start.go

@@ -73,6 +73,14 @@ func (s *Service) Start(ctx context.Context) (runError <-chan error, err error)
 	s.ports = ports
 	s.portMutex.Unlock()
 
+	if s.settings.UpCommand != "" {
+		err = runCommand(ctx, s.cmder, s.logger, s.settings.UpCommand, ports, s.settings.Interface)
+		if err != nil {
+			err = fmt.Errorf("running up command: %w", err)
+			s.logger.Error(err.Error())
+		}
+	}
+
 	keepPortCtx, keepPortCancel := context.WithCancel(context.Background())
 	s.keepPortCancel = keepPortCancel
 	runErrorCh := make(chan error)

internal/portforward/service/stop.go

@@ -3,7 +3,7 @@ package service
 import (
 	"context"
 	"fmt"
-	"os"
+	"time"
 )
 
 func (s *Service) Stop() (err error) {
@@ -30,6 +30,17 @@ func (s *Service) cleanup() (err error) {
 	s.portMutex.Lock()
 	defer s.portMutex.Unlock()
 
+	if s.settings.DownCommand != "" {
+		const downTimeout = 60 * time.Second
+		ctx, cancel := context.WithTimeout(context.Background(), downTimeout)
+		defer cancel()
+		err = runCommand(ctx, s.cmder, s.logger, s.settings.DownCommand, s.ports, s.settings.Interface)
+		if err != nil {
+			err = fmt.Errorf("running down command: %w", err)
+			s.logger.Error(err.Error())
+		}
+	}
+
 	for _, port := range s.ports {
 		err = s.portAllower.RemoveAllowedPort(context.Background(), port)
 		if err != nil {
@@ -48,11 +59,9 @@ func (s *Service) cleanup() (err error) {
 
 	s.ports = nil
 
-	filepath := s.settings.Filepath
-	s.logger.Info("removing 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/common/updater.go

@@ -13,6 +13,7 @@ var (
 	ErrNotEnoughServers     = errors.New("not enough servers found")
 	ErrHTTPStatusCodeNotOK  = errors.New("HTTP status code not OK")
 	ErrIPFetcherUnsupported = errors.New("IP fetcher not supported")
+	ErrCredentialsMissing   = errors.New("credentials missing")
 )
 
 type Fetcher interface {

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,
 	}
 }