Merge branch 'master' into restrictednet

- default to weekly instead of daily
- check gluetun-servers daily
- check some Go modules only quartely since they are not important

.github/ISSUE_TEMPLATE/bug.yml

@@ -56,7 +56,6 @@ body:
         - IVPN
         - Mullvad
         - NordVPN
-        - OVPN
         - Privado
         - Private Internet Access
         - PrivateVPN

.github/dependabot.yml

@@ -4,12 +4,38 @@ updates:
   - package-ecosystem: "github-actions"
     directory: "/"
     schedule:
-      interval: "daily"
+      interval: "weekly"
   - package-ecosystem: docker
     directory: /
     schedule:
-      interval: "daily"
-  - package-ecosystem: gomod
-    directory: /
+      interval: "weekly"
+  - # Servers data dependency that should be updated as soon as
+    # possible when a new version is released, to have the latest
+    # servers available
+    package-ecosystem: "gomod"
+    directory: "/"
     schedule:
-      interval: "daily"
+      interval: "weekly"
+    ignore:
+      - # In particular avoid amneziawg-go which have v1.x.y versions available
+        # on the Go modules proxy, but are not in the Github repository tags
+        # and are not the latest releases either. Most likely a mistake from the
+        # maintainers, which is persisted on the Go proxy.
+        dependency-name: "github.com/amnezia-vpn/amneziawg-go"
+        versions: ["1.x"]
+    groups:
+      low-importance:
+        patterns:
+          - "github.com/breml/rootcerts"
+          - "github.com/fatih/color"
+          - "github.com/golang/mock"
+          - "github.com/klauspost/compress"
+          - "github.com/klauspost/pgzip"
+          - "github.com/pelletier/go-toml/v2"
+          - "github.com/qdm12/goshutdown"
+          - "github.com/qdm12/gosplash"
+          - "github.com/qdm12/gotree"
+          - "github.com/qdm12/log"
+          - "github.com/stretchr/testify"
+          - "github.com/ulikunitz/xz"
+          - "gopkg.in/ini.v1"

.github/labels.yml

@@ -64,8 +64,6 @@
   color: "cfe8d4"
 - name: "☁️ NordVPN"
   color: "cfe8d4"
-- name: "☁️ OVPN"
-  color: "cfe8d4"
 - name: "☁️ Perfect Privacy"
   color: "cfe8d4"
 - name: "☁️ PIA"

.github/pull_request_template.md

@@ -8,5 +8,4 @@
 
 # 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

@@ -28,6 +28,10 @@ on:
       - go.mod
       - go.sum
 
+concurrency:
+  group: ${{ github.workflow }}-${{ github.event.pull_request.number || github.ref }}
+  cancel-in-progress: true
+
 jobs:
   verify:
     runs-on: ubuntu-latest
@@ -44,7 +48,6 @@ jobs:
           locale: "US"
           level: error
           exclude: |
-            ./internal/storage/servers.json
             ./.golangci.yml
             *.md
 
@@ -64,6 +67,10 @@ jobs:
           -v "$(pwd)/coverage.txt:/tmp/gobuild/coverage.txt" \
           test-container
 
+      - name: Run integration tests in test container
+        run: |
+          docker run --rm --entrypoint go test-container test -tags=integration ./internal/restrictednet
+
       - name: Verify dev cross platform compatibility
         run: docker build --target xcompile .
 
@@ -98,7 +105,7 @@ 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 ]
+    needs: [verify]
     runs-on: ubuntu-latest
     environment: secrets
     steps:
@@ -120,7 +127,8 @@ jobs:
 
       - name: Run Gluetun container with ProtonVPN Wireguard and port forwarding
           configuration
-        run: echo -e "${{ secrets.PROTONVPN_WIREGUARD_PRIVATE_KEY }}" | ./ci/runner
+        run:
+          echo -e "${{ secrets.PROTONVPN_WIREGUARD_PRIVATE_KEY }}" | ./ci/runner
           protonvpn-wireguard-port-forwarding
 
       - name: Run Gluetun container with ProtonVPN OpenVPN and port forwarding
@@ -129,11 +137,12 @@ jobs:
           secrets.PROTONVPN_OPENVPN_PASSWORD }}" | ./ci/runner
           protonvpn-openvpn-port-forwarding
 
-      - name: Run Gluetun container with Private Internet Access OpenVPN and port
-          forwarding configuration
-        run: echo -e "${{ secrets.PRIVATEINTERNETACCESS_OPENVPN_USER }}\n${{
-          secrets.PRIVATEINTERNETACCESS_OPENVPN_PASSWORD }}" | ./ci/runner
-          private-internet-access-openvpn-port-forwarding
+      # - name:
+      #     Run Gluetun container with Private Internet Access OpenVPN and port
+      #     forwarding configuration
+      #   run: echo -e "${{ secrets.PRIVATEINTERNETACCESS_OPENVPN_USER }}\n${{
+      #     secrets.PRIVATEINTERNETACCESS_OPENVPN_PASSWORD }}" | ./ci/runner
+      #     private-internet-access-openvpn-port-forwarding
 
       - name: Run Gluetun container with AirVPN Wireguard configuration
         run: echo -e "${{ secrets.AIRVPN_WIREGUARD_PRIVATE_KEY }}\n${{
@@ -141,7 +150,8 @@ jobs:
           secrets.AIRVPN_WIREGUARD_ADDRESSES }}" | ./ci/runner airvpn-wireguard
 
       - name: Run Gluetun container with AirVPN OpenVPN configuration
-        run: echo -e "${{ secrets.AIRVPN_OPENVPN_KEY }}\n${{ secrets.AIRVPN_OPENVPN_CERT
+        run:
+          echo -e "${{ secrets.AIRVPN_OPENVPN_KEY }}\n${{ secrets.AIRVPN_OPENVPN_CERT
           }}" | ./ci/runner airvpn-openvpn
 
   codeql:
@@ -169,7 +179,7 @@ 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, verify-private, codeql ]
+    needs: [verify, verify-private, codeql]
     permissions:
       actions: read
       contents: read

.github/workflows/markdown.yml

@@ -11,6 +11,10 @@ on:
       - "**.md"
       - .github/workflows/markdown.yml
 
+concurrency:
+  group: ${{ github.workflow }}-${{ github.event.pull_request.number || github.ref }}
+  cancel-in-progress: true
+
 jobs:
   markdown:
     runs-on: ubuntu-latest

.github/workflows/update-servers-list.yml

@@ -1,98 +0,0 @@
-name: Update servers list
-on:
-  workflow_dispatch:
-    inputs:
-      provider:
-        description: "VPN Provider to update"
-        required: true
-        default: "all"
-        type: choice
-        options:
-          - all
-          - airvpn
-          - cyberghost
-          - expressvpn
-          - fastestvpn
-          - giganews
-          - hidemyass
-          - ipvanish
-          - ivpn
-          - mullvad
-          - nordvpn
-          - perfect privacy
-          - privado
-          - private internet access
-          - privatevpn
-          - protonvpn
-          - purevpn
-          - slickvpn
-          - surfshark
-          - torguard
-          - vpnsecure
-          - vpn unlimited
-          - vyprvpn
-          - windscribe
-  schedule:
-    - cron: "11 3 1 */2 *" # Run at 03:11 on the 1st of every 2nd month
-jobs:
-  update-servers-list:
-    if: github.repository == 'passteque/gluetun'
-    runs-on: ubuntu-latest
-    permissions:
-      actions: read
-      contents: write
-      pull-requests: write
-    steps:
-      - uses: actions/checkout@v6
-
-      - uses: actions/setup-go@v6
-        with:
-          go-version-file: go.mod
-
-      - name: Update servers list
-        run: |
-          SELECTED_PROVIDER="${{ github.event.inputs.provider || 'all' }}"
-
-          if [ "$SELECTED_PROVIDER" = "all" ]; then
-            FLAGS="-all"
-          else
-            FLAGS="-providers $SELECTED_PROVIDER"
-          fi
-
-          go run ./cmd/gluetun/main.go update $FLAGS \
-            -maintainer \
-            -proton-email "${{ secrets.PROTON_EMAIL }}" \
-            -proton-password "${{ secrets.PROTON_PASSWORD }}"
-
-      - name: Check for changes
-        run: |
-          if git diff --exit-code internal/storage/servers.json >/dev/null; then
-            echo "Error: internal/storage/servers.json was not modified."
-            exit 1
-          fi
-
-      - name: Check no other file changes
-        run: |
-          if ! git diff --exit-code --quiet ':!internal/storage/servers.json'; then
-            echo "Error: Unexpected changes detected in files other than servers.json"
-            git status --short
-            exit 1
-          fi
-
-      - name: Create Pull Request
-        id: createpr
-        uses: peter-evans/create-pull-request@v8
-        with:
-          branch-suffix: timestamp
-          branch: bot/update-servers-list
-          base: master
-          delete-branch: true
-          title: "feat(providers/${{ github.event.inputs.provider || 'all' }}): servers data update"
-          body: |
-            This PR was automatically generated by the [Update servers list](${{ github.server_url }}/${{ github.repository }}/actions/runs/${{ github.run_id }}) workflow run.
-
-      # - name: Merge Pull Request
-      #   env:
-      #     GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
-      #   run: |
-      #     gh pr merge ${{ steps.createpr.outputs.pull-request-number }} --auto -m -d

.golangci.yml

@@ -12,6 +12,10 @@ formatters:
       - builtin$
       - examples$
 
+run:
+  build-tags:
+    - integration
+
 linters:
   settings:
     misspell:

.vscode/settings.json

@@ -3,7 +3,7 @@
   // to develop this project.
   "files.eol": "\n",
   "editor.formatOnSave": true,
-  "go.buildTags": "linux",
+  "go.buildTags": "linux,integration",
   "go.toolsEnvVars": {
     "CGO_ENABLED": "0"
   },

AGENTS.md

@@ -50,6 +50,7 @@ Guidance for coding agents working in this repository.
 - Prefer splitting a code line only when it triggers the `lll` linter, do not split a command or arguments list for each element
 - Use `netip` types instead of `net` types whenever possible
 - Use constants instead of variables whenever possible, especially function-local inline constants.
+- Prefer using pure functions over methods when possible. Especially if the method does not need any fields from the receiving struct, it should be a pure function.
 - Do not use `time.Sleep`, prefer using a `time.Timer` with a `select` statement also listening on a context cancelation
 - `panic`:
   - should only be used when a programming error is encountered and you should NOT return errors for programming errors (such as passing nil objects)
@@ -115,6 +116,7 @@ Mocking works with the `go.uber.org/mock` library, and the `mockgen` tool.
   - **Never** use `.AnyTimes()` on mocks. Always define the number of times a certain mock call should be called, with `.Times(3)` for example.
   - **Always** set the `.Return(...)` on the mock if the function returns something.
   - Avoid using **mock helpers** functions, prefer a bit of repetition than tight coupling and dependency
+  - Always define the gomock controller `ctrl` in the subtest and not in the parent test, or a subtest mock failing will crash all the other subtests.
 
 ### main.go
 
@@ -127,6 +129,7 @@ The Go formatter used is gofumpt.
 ### Errors
 
 - Always prefer wrapping errors with some context with `fmt.Errorf("doing this: %w", err)`
+- Use `errors.New("error message")` when creating a 'bottom' constant string error without additional context, instead of `fmt.Errorf`
 - In rare cases, you can just use `return err` notably:
   - If the function is called **recursively**, since we don't wrap the wrapping multiple times for each recursion
   - If the current function only statement is the call to another function, for example:
@@ -179,6 +182,8 @@ The Go formatter used is gofumpt.
 
 - Do not use `http.DefaultClient`, use a custom `*http.Client` with a fixed timeout and share with dependency injections.
 - Do not check for injected dependencies being `nil`, prefer to just panic on a nil pointer. By default it's fine to panic if a developer injects a dependency `nil`. `nil` does not mean use a default.
+- Prefer using a `switch { case ...}` statement over multiple consecutive `if` statements to have shorter code.
+- Prefer using `[...]T` instead of `[]T` when the length is fixed and known at compile time, to avoid unnecessary allocations.
 
 ## Validation checklist
 

Dockerfile

@@ -186,14 +186,12 @@ ENV VPN_SERVICE_PROVIDER=pia \
     # # ProtonVPN only:
     SECURE_CORE_ONLY= \
     TOR_ONLY= \
-    # # Surfshark and ovpn only:
+    # # Surfshark only:
     MULTIHOP_ONLY= \
     # # VPN Secure only:
     PREMIUM_ONLY= \
     # # PIA and ProtonVPN only:
     PORT_FORWARD_ONLY= \
-    # # Ovpn only:
-    SERVER_DEDICATED=no \
     # Firewall
     FIREWALL_ENABLED_DISABLING_IT_SHOOTS_YOU_IN_YOUR_FOOT=on \
     FIREWALL_VPN_INPUT_PORTS= \
@@ -278,7 +276,7 @@ ENV VPN_SERVICE_PROVIDER=pia \
     PUID=1000 \
     PGID=1000
 ENTRYPOINT ["/gluetun-entrypoint"]
-EXPOSE 8000/tcp 8888/tcp 8388/tcp 8388/udp 1080/tcp
+EXPOSE 8000/tcp 8888/tcp 8388/tcp 8388/udp 1080/tcp 1080/udp
 HEALTHCHECK --interval=5s --timeout=5s --start-period=10s --retries=3 CMD /gluetun-entrypoint healthcheck
 ARG TARGETPLATFORM
 RUN apk add --no-cache --update -l wget && \

README.md

@@ -60,10 +60,10 @@ Lightweight swiss-army-knife-like VPN client to multiple VPN service providers
 ## Features
 
 - Based on Alpine 3.23 for a small Docker image of 43.1MB
-- Supports: **AirVPN**, **Cyberghost**, **ExpressVPN**, **FastestVPN**, **Giganews**, **HideMyAss**, **IPVanish**, **IVPN**, **Mullvad** (Wireguard only), **NordVPN**, **Ovpn**, **Perfect Privacy**, **Privado**, **Private Internet Access**, **PrivateVPN**, **ProtonVPN**, **PureVPN**,  **SlickVPN**, **Surfshark**, **TorGuard**, **VPNSecure.me**, **VPNUnlimited**, **Vyprvpn**, **Windscribe** servers
+- Supports: **AirVPN**, **Cyberghost**, **ExpressVPN**, **FastestVPN**, **Giganews**, **HideMyAss**, **IPVanish**, **IVPN**, **Mullvad** (Wireguard only), **NordVPN**, **Perfect Privacy**, **Privado**, **Private Internet Access**, **PrivateVPN**, **ProtonVPN**, **PureVPN**,  **SlickVPN**, **Surfshark**, **TorGuard**, **VPNSecure.me**, **VPNUnlimited**, **Vyprvpn**, **Windscribe** servers
 - Supports OpenVPN for all providers listed
 - Supports Wireguard both kernelspace and userspace
-  - For **AirVPN**, **FastestVPN**, **Ivpn**, **Mullvad**, **NordVPN**, **Ovpn**, **Perfect privacy**, **ProtonVPN**, **Surfshark** and **Windscribe**
+  - For **AirVPN**, **FastestVPN**, **Ivpn**, **Mullvad**, **NordVPN**, **Perfect privacy**, **ProtonVPN**, **Surfshark** and **Windscribe**
   - For **Cyberghost**, **Private Internet Access**, **PrivateVPN**, **PureVPN**, **Torguard**, **VPN Unlimited** and **VyprVPN** using [the custom provider](https://github.com/qdm12/gluetun-wiki/blob/main/setup/providers/custom.md)
   - For custom Wireguard configurations using [the custom provider](https://github.com/qdm12/gluetun-wiki/blob/main/setup/providers/custom.md)
   - More in progress, see [#134](https://github.com/passteque/gluetun/issues/134)
@@ -73,7 +73,7 @@ Lightweight swiss-army-knife-like VPN client to multiple VPN service providers
 - Choose the vpn network protocol, `udp` or `tcp`
 - Built in firewall kill switch to allow traffic only with needed the VPN servers and LAN devices
 - Built in Shadowsocks proxy server (protocol based on SOCKS5 with an encryption layer, tunnels TCP+UDP)
-- Built in Socks5 proxy server (tunnels TCP) - partial credits to @angelakis and @adjscent
+- Built in Socks5 proxy server (tunnels TCP+UDP) - partial credits to @angelakis and @adjscent
 - Built in HTTP proxy (tunnels HTTP and HTTPS through TCP)
 - [Connect other containers to it](https://github.com/qdm12/gluetun-wiki/blob/main/setup/connect-a-container-to-gluetun.md)
 - [Connect LAN devices to it](https://github.com/qdm12/gluetun-wiki/blob/main/setup/connect-a-lan-device-to-gluetun.md)

go.mod

@@ -15,7 +15,7 @@ require (
 	github.com/mdlayher/netlink v1.9.0
 	github.com/pelletier/go-toml/v2 v2.2.4
 	github.com/qdm12/dns/v2 v2.0.0-rc9.0.20260421173011-9de8e7fdbe3a
-	github.com/qdm12/gluetun-servers v0.1.1-0.20260522005421-14277e92ce82
+	github.com/qdm12/gluetun-servers v0.1.0
 	github.com/qdm12/goservices v0.1.1-0.20251104135713-6bee97bd4978
 	github.com/qdm12/gosettings v0.4.4
 	github.com/qdm12/goshutdown v0.3.0
@@ -27,10 +27,9 @@ require (
 	github.com/ti-mo/netfilter v0.5.3
 	github.com/ulikunitz/xz v0.5.15
 	github.com/youmark/pkcs8 v0.0.0-20201027041543-1326539a0a0a
-	golang.org/x/exp v0.0.0-20241009180824-f66d83c29e7c
-	golang.org/x/net v0.51.0
-	golang.org/x/sys v0.42.0
-	golang.org/x/text v0.35.0
+	golang.org/x/net v0.55.0
+	golang.org/x/sys v0.45.0
+	golang.org/x/text v0.37.0
 	golang.zx2c4.com/wireguard v0.0.0-20231211153847-12269c276173
 	golang.zx2c4.com/wireguard/wgctrl v0.0.0-20230429144221-925a1e7659e6
 	gopkg.in/ini.v1 v1.67.1
@@ -57,10 +56,11 @@ require (
 	github.com/prometheus/common v0.60.1 // indirect
 	github.com/prometheus/procfs v0.15.1 // indirect
 	github.com/riobard/go-bloom v0.0.0-20200614022211-cdc8013cb5b3 // indirect
-	golang.org/x/crypto v0.48.0 // indirect
-	golang.org/x/mod v0.33.0 // indirect
+	golang.org/x/crypto v0.51.0 // indirect
+	golang.org/x/exp v0.0.0-20241009180824-f66d83c29e7c // indirect
+	golang.org/x/mod v0.35.0 // indirect
 	golang.org/x/sync v0.20.0 // indirect
-	golang.org/x/tools v0.42.0 // indirect
+	golang.org/x/tools v0.44.0 // 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

@@ -76,8 +76,8 @@ github.com/prometheus/procfs v0.15.1 h1:YagwOFzUgYfKKHX6Dr+sHT7km/hxC76UB0leargg
 github.com/prometheus/procfs v0.15.1/go.mod h1:fB45yRUv8NstnjriLhBQLuOUt+WW4BsoGhij/e3PBqk=
 github.com/qdm12/dns/v2 v2.0.0-rc9.0.20260421173011-9de8e7fdbe3a h1:TE157yPQmAbVruH0MWCQzs0vTT/6t96DkoWUXd6PVuc=
 github.com/qdm12/dns/v2 v2.0.0-rc9.0.20260421173011-9de8e7fdbe3a/go.mod h1:98foWgXJZ+g8gJIuO+fdO+oWpFei5WShMFTeN4Im2lE=
-github.com/qdm12/gluetun-servers v0.1.1-0.20260522005421-14277e92ce82 h1:tE44IEW7o9yPQaO8HBeoO9RxtTTxqhboIypegrQlVt8=
-github.com/qdm12/gluetun-servers v0.1.1-0.20260522005421-14277e92ce82/go.mod h1:acttuyHyoFDu6GTbf3kAV+QXeiX8oJeh0MBic67/9z8=
+github.com/qdm12/gluetun-servers v0.1.0 h1:w9JLghKZwI0Gzpp9p5rNANgEYUUZ1dxdxsG6NKIojaY=
+github.com/qdm12/gluetun-servers v0.1.0/go.mod h1:acttuyHyoFDu6GTbf3kAV+QXeiX8oJeh0MBic67/9z8=
 github.com/qdm12/goservices v0.1.1-0.20251104135713-6bee97bd4978 h1:TRGpCU1l0lNwtogEUSs5U+RFceYxkAJUmrGabno7J5c=
 github.com/qdm12/goservices v0.1.1-0.20251104135713-6bee97bd4978/go.mod h1:D1Po4CRQLYjccnAR2JsVlN1sBMgQrcNLONbvyuzcdTg=
 github.com/qdm12/gosettings v0.4.4 h1:SM6tOZDf6k8qbjWU8KWyBF4mWIixfsKCfh9DGRLHlj4=
@@ -120,15 +120,15 @@ golang.org/x/crypto v0.0.0-20191011191535-87dc89f01550/go.mod h1:yigFU9vqHzYiE8U
 golang.org/x/crypto v0.0.0-20200302210943-78000ba7a073/go.mod h1:LzIPMQfyMNhhGPhUkYOs5KpL4U8rLKemX1yGLhDgUto=
 golang.org/x/crypto v0.0.0-20210921155107-089bfa567519/go.mod h1:GvvjBRRGRdwPK5ydBHafDWAxML/pGHZbMvKqRZ5+Abc=
 golang.org/x/crypto v0.7.0/go.mod h1:pYwdfH91IfpZVANVyUOhSIPZaFoJGxTFbZhFTx+dXZU=
-golang.org/x/crypto v0.48.0 h1:/VRzVqiRSggnhY7gNRxPauEQ5Drw9haKdM0jqfcCFts=
-golang.org/x/crypto v0.48.0/go.mod h1:r0kV5h3qnFPlQnBSrULhlsRfryS2pmewsg+XfMgkVos=
+golang.org/x/crypto v0.51.0 h1:IBPXwPfKxY7cWQZ38ZCIRPI50YLeevDLlLnyC5wRGTI=
+golang.org/x/crypto v0.51.0/go.mod h1:8AdwkbraGNABw2kOX6YFPs3WM22XqI4EXEd8g+x7Oc8=
 golang.org/x/exp v0.0.0-20241009180824-f66d83c29e7c h1:7dEasQXItcW1xKJ2+gg5VOiBnqWrJc+rq0DPKyvvdbY=
 golang.org/x/exp v0.0.0-20241009180824-f66d83c29e7c/go.mod h1:NQtJDoLvd6faHhE7m4T/1IY708gDefGGjR/iUW8yQQ8=
 golang.org/x/mod v0.4.2/go.mod h1:s0Qsj1ACt9ePp/hMypM3fl4fZqREWJwdYDEqhRiZZUA=
 golang.org/x/mod v0.6.0-dev.0.20220419223038-86c51ed26bb4/go.mod h1:jJ57K6gSWd91VN4djpZkiMVwK6gcyfeH4XE8wZrZaV4=
 golang.org/x/mod v0.8.0/go.mod h1:iBbtSCu2XBx23ZKBPSOrRkjjQPZFPuis4dIYUhu/chs=
-golang.org/x/mod v0.33.0 h1:tHFzIWbBifEmbwtGz65eaWyGiGZatSrT9prnU8DbVL8=
-golang.org/x/mod v0.33.0/go.mod h1:swjeQEj+6r7fODbD2cqrnje9PnziFuw4bmLbBZFrQ5w=
+golang.org/x/mod v0.35.0 h1:Ww1D637e6Pg+Zb2KrWfHQUnH2dQRLBQyAtpr/haaJeM=
+golang.org/x/mod v0.35.0/go.mod h1:+GwiRhIInF8wPm+4AoT6L0FA1QWAad3OMdTRx4tFYlU=
 golang.org/x/net v0.0.0-20190404232315-eb5bcb51f2a3/go.mod h1:t9HGtf8HONx5eT2rtn7q6eTqICYqUVnKs3thJo3Qplg=
 golang.org/x/net v0.0.0-20190620200207-3b0461eec859/go.mod h1:z5CRVTTTmAJ677TzLLGU+0bjPO0LkuOLi4/5GtJWs/s=
 golang.org/x/net v0.0.0-20210226172049-e18ecbb05110/go.mod h1:m0MpNAwzfU5UDzcl9v0D8zg8gWTRqZa9RBIspLL5mdg=
@@ -136,8 +136,8 @@ golang.org/x/net v0.0.0-20210405180319-a5a99cb37ef4/go.mod h1:p54w0d4576C0XHj96b
 golang.org/x/net v0.0.0-20220722155237-a158d28d115b/go.mod h1:XRhObCWvk6IyKnWLug+ECip1KBveYUHfp+8e9klMJ9c=
 golang.org/x/net v0.6.0/go.mod h1:2Tu9+aMcznHK/AK1HMvgo6xiTLG5rD5rZLDS+rp2Bjs=
 golang.org/x/net v0.8.0/go.mod h1:QVkue5JL9kW//ek3r6jTKnTFis1tRmNAW2P1shuFdJc=
-golang.org/x/net v0.51.0 h1:94R/GTO7mt3/4wIKpcR5gkGmRLOuE/2hNGeWq/GBIFo=
-golang.org/x/net v0.51.0/go.mod h1:aamm+2QF5ogm02fjy5Bb7CQ0WMt1/WVM7FtyaTLlA9Y=
+golang.org/x/net v0.55.0 h1:bcvxaJn3e1U6InsFWt1JUq1aSjnRxLzT2rtD2KfkDF8=
+golang.org/x/net v0.55.0/go.mod h1:L5U2KuzuOe1lY7Z+aWVIKK6qEeJXnXV9yzGA+WCHJww=
 golang.org/x/sync v0.0.0-20190423024810-112230192c58/go.mod h1:RxMgew5VJxzue5/jJTE5uejpjVlOe/izrB70Jof72aM=
 golang.org/x/sync v0.0.0-20210220032951-036812b2e83c/go.mod h1:RxMgew5VJxzue5/jJTE5uejpjVlOe/izrB70Jof72aM=
 golang.org/x/sync v0.0.0-20220722155255-886fb9371eb4/go.mod h1:RxMgew5VJxzue5/jJTE5uejpjVlOe/izrB70Jof72aM=
@@ -156,8 +156,8 @@ golang.org/x/sys v0.0.0-20220722155257-8c9f86f7a55f/go.mod h1:oPkhp1MJrh7nUepCBc
 golang.org/x/sys v0.0.0-20220811171246-fbc7d0a398ab/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
 golang.org/x/sys v0.5.0/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
 golang.org/x/sys v0.6.0/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
-golang.org/x/sys v0.42.0 h1:omrd2nAlyT5ESRdCLYdm3+fMfNFE/+Rf4bDIQImRJeo=
-golang.org/x/sys v0.42.0/go.mod h1:4GL1E5IUh+htKOUEOaiffhrAeqysfVGipDYzABqnCmw=
+golang.org/x/sys v0.45.0 h1:dO4czNzziLiiXplLQgBCEpCvXQ3dnkn0SdaZSYdQ+FY=
+golang.org/x/sys v0.45.0/go.mod h1:4GL1E5IUh+htKOUEOaiffhrAeqysfVGipDYzABqnCmw=
 golang.org/x/term v0.0.0-20201126162022-7de9c90e9dd1/go.mod h1:bj7SfCRtBDWHUb9snDiAeCFNEtKQo2Wmx5Cou7ajbmo=
 golang.org/x/term v0.0.0-20210927222741-03fcf44c2211/go.mod h1:jbD1KX2456YbFQfuXm/mYQcufACuNUgVhRMnK/tPxf8=
 golang.org/x/term v0.5.0/go.mod h1:jMB1sMXY+tzblOD4FWmEbocvup2/aLOaQEp7JmGp78k=
@@ -167,8 +167,8 @@ golang.org/x/text v0.3.3/go.mod h1:5Zoc/QRtKVWzQhOtBMvqHzDpF6irO9z98xDceosuGiQ=
 golang.org/x/text v0.3.7/go.mod h1:u+2+/6zg+i71rQMx5EYifcz6MCKuco9NR6JIITiCfzQ=
 golang.org/x/text v0.7.0/go.mod h1:mrYo+phRRbMaCq/xk9113O4dZlRixOauAjOtrjsXDZ8=
 golang.org/x/text v0.8.0/go.mod h1:e1OnstbJyHTd6l/uOt8jFFHp6TRDWZR/bV3emEE/zU8=
-golang.org/x/text v0.35.0 h1:JOVx6vVDFokkpaq1AEptVzLTpDe9KGpj5tR4/X+ybL8=
-golang.org/x/text v0.35.0/go.mod h1:khi/HExzZJ2pGnjenulevKNX1W67CUy0AsXcNubPGCA=
+golang.org/x/text v0.37.0 h1:Cqjiwd9eSg8e0QAkyCaQTNHFIIzWtidPahFWR83rTrc=
+golang.org/x/text v0.37.0/go.mod h1:a5sjxXGs9hsn/AJVwuElvCAo9v8QYLzvavO5z2PiM38=
 golang.org/x/time v0.9.0 h1:EsRrnYcQiGH+5FfbgvV4AP7qEZstoyrHB0DzarOQ4ZY=
 golang.org/x/time v0.9.0/go.mod h1:3BpzKBy/shNhVucY/MWOyx10tF3SFh9QdLuxbVysPQM=
 golang.org/x/tools v0.0.0-20180917221912-90fa682c2a6e/go.mod h1:n7NCudcB/nEzxVGmLbDWY5pfWTLqBcC2KZ6jyYvM4mQ=
@@ -176,8 +176,8 @@ golang.org/x/tools v0.0.0-20191119224855-298f0cb1881e/go.mod h1:b+2E5dAYhXwXZwtn
 golang.org/x/tools v0.1.1/go.mod h1:o0xws9oXOQQZyjljx8fwUC0k7L1pTE6eaCbjGeHmOkk=
 golang.org/x/tools v0.1.12/go.mod h1:hNGJHUnrk76NpqgfD5Aqm5Crs+Hm0VOH/i9J2+nxYbc=
 golang.org/x/tools v0.6.0/go.mod h1:Xwgl3UAJ/d3gWutnCtw505GrjyAbvKui8lOU390QaIU=
-golang.org/x/tools v0.42.0 h1:uNgphsn75Tdz5Ji2q36v/nsFSfR/9BRFvqhGBaJGd5k=
-golang.org/x/tools v0.42.0/go.mod h1:Ma6lCIwGZvHK6XtgbswSoWroEkhugApmsXyrUmBhfr0=
+golang.org/x/tools v0.44.0 h1:UP4ajHPIcuMjT1GqzDWRlalUEoY+uzoZKnhOjbIPD2c=
+golang.org/x/tools v0.44.0/go.mod h1:KA0AfVErSdxRZIsOVipbv3rQhVXTnlU6UhKxHd1seDI=
 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/update.go

@@ -5,6 +5,7 @@ import (
 	"errors"
 	"flag"
 	"fmt"
+	"net"
 	"net/http"
 	"slices"
 	"strings"
@@ -104,6 +105,10 @@ func (c *CLI) Update(ctx context.Context, args []string, logger UpdaterLogger) e
 	if err != nil {
 		return fmt.Errorf("creating DoH dialer: %w", err)
 	}
+	net.DefaultResolver = &net.Resolver{
+		PreferGo: true,
+		Dial:     dnsDialer.Dial,
+	}
 
 	const clientTimeout = 10 * time.Second
 	httpClient := &http.Client{Timeout: clientTimeout}

internal/command/start.go

@@ -9,8 +9,9 @@ import (
 )
 
 // Start launches a command and streams stdout and stderr to channels.
-// All the channels returned are ready only and won't be closed
-// if the command fails later.
+// stdoutLines and stderrLines channels will be closed when there is no more
+// output to read, in order for the caller to catch all lines even after the
+// command has finished. The waitError channel returned will never be closed.
 func (c *Cmder) Start(cmd *exec.Cmd) (
 	stdoutLines, stderrLines <-chan string,
 	waitError <-chan error, startErr error,
@@ -38,6 +39,7 @@ func start(cmd execCmd) (stdoutLines, stderrLines <-chan string,
 	if err != nil {
 		_ = stdout.Close()
 		<-stdoutDone
+		close(stdoutLinesCh)
 		return nil, nil, nil, err
 	}
 	go streamToChannel(stderrReady, stderrDone, stderr, stderrLinesCh)
@@ -45,9 +47,11 @@ func start(cmd execCmd) (stdoutLines, stderrLines <-chan string,
 	err = cmd.Start()
 	if err != nil {
 		_ = stdout.Close()
-		_ = stderr.Close()
 		<-stdoutDone
+		close(stdoutLinesCh)
+		_ = stderr.Close()
 		<-stderrDone
+		close(stderrLinesCh)
 		return nil, nil, nil, err
 	}
 
@@ -55,8 +59,10 @@ func start(cmd execCmd) (stdoutLines, stderrLines <-chan string,
 	go func() {
 		err := cmd.Wait()
 		<-stdoutDone
-		<-stderrDone
+		close(stdoutLinesCh)
 		_ = stdout.Close()
+		<-stderrDone
+		close(stderrLinesCh)
 		_ = stderr.Close()
 		waitErrorCh <- err
 	}()

internal/command/start_test.go

@@ -89,30 +89,48 @@ func Test_start(t *testing.T) {
 
 			require.NoError(t, err)
 
-			var stdoutIndex, stderrIndex int
-
-			done := false
-			for !done {
-				select {
-				case line := <-stdoutLines:
-					assert.Equal(t, testCase.stdout[stdoutIndex], line)
-					stdoutIndex++
-				case line := <-stderrLines:
-					assert.Equal(t, testCase.stderr[stderrIndex], line)
-					stderrIndex++
-				case err := <-waitError:
-					if testCase.waitErr != nil {
-						require.Error(t, err)
-						assert.Equal(t, testCase.waitErr.Error(), err.Error())
-					} else {
-						assert.NoError(t, err)
-					}
-					done = true
-				}
-			}
-
-			assert.Equal(t, len(testCase.stdout), stdoutIndex)
-			assert.Equal(t, len(testCase.stderr), stderrIndex)
+			collectAndCheckChannels(t, stdoutLines, stderrLines, waitError,
+				testCase.stdout, testCase.stderr, testCase.waitErr)
 		})
 	}
 }
+
+func collectAndCheckChannels(t *testing.T, stdoutLines, stderrLines <-chan string,
+	waitError <-chan error, expectedStdout, expectedStderr []string, expectedWaitErr error,
+) {
+	t.Helper()
+
+	stdoutIndex := 0
+	stderrIndex := 0
+
+	done := false
+	for !done {
+		select {
+		case line, ok := <-stdoutLines:
+			if !ok {
+				stdoutLines = nil
+				continue
+			}
+			assert.Equal(t, expectedStdout[stdoutIndex], line)
+			stdoutIndex++
+		case line, ok := <-stderrLines:
+			if !ok {
+				stderrLines = nil
+				continue
+			}
+			assert.Equal(t, expectedStderr[stderrIndex], line)
+			stderrIndex++
+		case err := <-waitError:
+			if expectedWaitErr != nil {
+				require.Error(t, err)
+				assert.Equal(t, expectedWaitErr.Error(), err.Error())
+			} else {
+				assert.NoError(t, err)
+			}
+			done = true
+		}
+	}
+
+	assert.Equal(t, len(expectedStdout), stdoutIndex)
+	assert.Equal(t, len(expectedStderr), stderrIndex)
+}

internal/command/startnlog.go

@@ -18,31 +18,37 @@ func (c *Cmder) RunAndLog(ctx context.Context, command string, logger Logger) (e
 		return err
 	}
 
-	streamCtx, streamCancel := context.WithCancel(context.Background())
 	streamDone := make(chan struct{})
-	go streamLines(streamCtx, streamDone, logger, stdout, stderr)
+	go streamLines(streamDone, logger, stdout, stderr)
 
 	err = <-waitError
-	streamCancel()
 	<-streamDone
 	return err
 }
 
-func streamLines(ctx context.Context, done chan<- struct{},
-	logger Logger, stdout, stderr <-chan string,
+func streamLines(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)
+		case line, ok := <-stdout:
+			if ok {
+				logger.Info(line)
+			}
+			if stderr == nil {
+				return
+			}
+			stdout = nil
+		case line, ok := <-stderr:
+			if ok {
+				logger.Error(line)
+			}
+			if stdout == nil {
+				return
+			}
+			stderr = nil
 		}
 	}
 }

internal/configuration/settings/deprecated.go

@@ -1,10 +1,10 @@
 package settings
 
 import (
+	"maps"
 	"slices"
 
 	"github.com/qdm12/gosettings/reader"
-	"golang.org/x/exp/maps"
 )
 
 func readObsolete(r *reader.Reader) (warnings []string) {
@@ -17,7 +17,7 @@ func readObsolete(r *reader.Reader) (warnings []string) {
 		"DNS_KEEP_NAMESERVER": "DNS_KEEP_NAMESERVER is obsolete because you should use the built-in server which now " +
 			"forwards local names to private DNS resolvers found in /etc/resolv.conf at container start",
 	}
-	sortedKeys := maps.Keys(keyToMessage)
+	sortedKeys := slices.Collect(maps.Keys(keyToMessage))
 	slices.Sort(sortedKeys)
 	warnings = make([]string, 0, len(keyToMessage))
 	for _, key := range sortedKeys {

internal/configuration/settings/openvpnselection.go

@@ -70,7 +70,7 @@ func (o OpenVPNSelection) validate(vpnProvider string) (err error) {
 		switch vpnProvider {
 		// no restriction on port
 		case providers.Custom, providers.Cyberghost, providers.HideMyAss,
-			providers.Ovpn, providers.Privatevpn, providers.Torguard:
+			providers.Privatevpn, providers.Torguard:
 		// no custom port allowed
 		case providers.Expressvpn, providers.Fastestvpn,
 			providers.Giganews, providers.Ipvanish,

internal/configuration/settings/portforward.go

@@ -95,7 +95,7 @@ func (p PortForwarding) Validate(vpnProvider string) (err error) {
 			return errors.New("port forwarding password is empty")
 		}
 	case providers.Protonvpn:
-		const maxPortsCount = 4
+		const maxPortsCount = 5
 		if p.PortsCount > maxPortsCount {
 			return fmt.Errorf("ports count too high: %d > %d", p.PortsCount, maxPortsCount)
 		}

internal/configuration/settings/provider.go

@@ -49,7 +49,6 @@ func (p *Provider) validate(vpnType string, filterChoicesGetter FilterChoicesGet
 			providers.Ivpn,
 			providers.Mullvad,
 			providers.Nordvpn,
-			providers.Ovpn,
 			providers.Protonvpn,
 			providers.Surfshark,
 			providers.Windscribe,

internal/configuration/settings/serverselection.go

@@ -63,9 +63,6 @@ type ServerSelection struct {
 	// TorOnly is true if VPN servers without tor should
 	// be filtered. This is used with ProtonVPN.
 	TorOnly *bool `json:"tor_only"`
-	// Dedicated is true if dedicated VPN servers should be chosen only.
-	// This is used with OVPN.
-	Dedicated *bool `json:"dedicated"`
 	// OpenVPN contains settings to select OpenVPN servers
 	// and the final connection.
 	OpenVPN OpenVPNSelection `json:"openvpn"`
@@ -275,8 +272,6 @@ func validateFeatureFilters(settings ServerSelection, vpnServiceProvider string)
 		return errors.New("secure core only filter is not supported")
 	case *settings.TorOnly && vpnServiceProvider != providers.Protonvpn:
 		return errors.New("tor only filter is not supported")
-	case *settings.Dedicated && vpnServiceProvider != providers.Ovpn:
-		return errors.New("dedicated filter is not supported")
 	default:
 		return nil
 	}
@@ -301,7 +296,6 @@ func (ss *ServerSelection) copy() (copied ServerSelection) {
 		TorOnly:         gosettings.CopyPointer(ss.TorOnly),
 		PortForwardOnly: gosettings.CopyPointer(ss.PortForwardOnly),
 		MultiHopOnly:    gosettings.CopyPointer(ss.MultiHopOnly),
-		Dedicated:       gosettings.CopyPointer(ss.Dedicated),
 		OpenVPN:         ss.OpenVPN.copy(),
 		Wireguard:       ss.Wireguard.copy(),
 	}
@@ -325,7 +319,6 @@ func (ss *ServerSelection) overrideWith(other ServerSelection) {
 	ss.TorOnly = gosettings.OverrideWithPointer(ss.TorOnly, other.TorOnly)
 	ss.MultiHopOnly = gosettings.OverrideWithPointer(ss.MultiHopOnly, other.MultiHopOnly)
 	ss.PortForwardOnly = gosettings.OverrideWithPointer(ss.PortForwardOnly, other.PortForwardOnly)
-	ss.Dedicated = gosettings.OverrideWithPointer(ss.Dedicated, other.Dedicated)
 	ss.OpenVPN.overrideWith(other.OpenVPN)
 	ss.Wireguard.overrideWith(other.Wireguard)
 }
@@ -342,7 +335,6 @@ func (ss *ServerSelection) setDefaults(vpnProvider string, portForwardingEnabled
 	defaultPortForwardOnly := portForwardingEnabled &&
 		helpers.IsOneOf(vpnProvider, providers.PrivateInternetAccess, providers.Protonvpn)
 	ss.PortForwardOnly = gosettings.DefaultPointer(ss.PortForwardOnly, defaultPortForwardOnly)
-	ss.Dedicated = gosettings.DefaultPointer(ss.Dedicated, false)
 	ss.OpenVPN.setDefaults(vpnProvider)
 	ss.Wireguard.setDefaults()
 }
@@ -418,10 +410,6 @@ func (ss ServerSelection) toLinesNode() (node *gotree.Node) {
 		node.Appendf("Multi-hop only servers: yes")
 	}
 
-	if *ss.Dedicated {
-		node.Appendf("Dedicated servers: yes")
-	}
-
 	if *ss.PortForwardOnly {
 		node.Appendf("Port forwarding only servers: yes")
 	}
@@ -513,12 +501,6 @@ func (ss *ServerSelection) read(r *reader.Reader,
 		return err
 	}
 
-	// Ovpn only
-	ss.Dedicated, err = r.BoolPtr("SERVER_DEDICATED")
-	if err != nil {
-		return err
-	}
-
 	err = ss.OpenVPN.read(r)
 	if err != nil {
 		return err

internal/configuration/settings/wireguardselection.go

@@ -5,7 +5,6 @@ import (
 	"fmt"
 	"net/netip"
 
-	"github.com/qdm12/gluetun/internal/configuration/settings/helpers"
 	"github.com/qdm12/gluetun/internal/constants/providers"
 	"github.com/qdm12/gosettings"
 	"github.com/qdm12/gosettings/reader"
@@ -23,7 +22,7 @@ type WireguardSelection struct {
 	// 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, Ovpn, Surfshark
+	// It is optional for VPN providers IVPN, Mullvad, Surfshark
 	// and Windscribe, and compulsory for the others.
 	// When optional, it can be set to 0 to indicate not use
 	// a custom endpoint port. It cannot be nil in the internal
@@ -41,9 +40,8 @@ func (w WireguardSelection) validate(vpnProvider string) (err error) {
 	// Validate EndpointIP
 	switch vpnProvider {
 	case providers.Airvpn, providers.Fastestvpn, providers.Ivpn,
-		providers.Mullvad, providers.Nordvpn, providers.Ovpn,
-		providers.Protonvpn, providers.Surfshark,
-		providers.Windscribe:
+		providers.Mullvad, providers.Nordvpn, providers.Protonvpn,
+		providers.Surfshark, providers.Windscribe:
 		// endpoint IP addresses are baked in
 	case providers.Custom:
 		if !w.EndpointIP.IsValid() || w.EndpointIP.IsUnspecified() {
@@ -65,16 +63,12 @@ func (w WireguardSelection) validate(vpnProvider string) (err error) {
 		if *w.EndpointPort != 0 {
 			return errors.New("endpoint port is set")
 		}
-	case providers.Airvpn, providers.Ivpn, providers.Mullvad,
-		providers.Ovpn, providers.Windscribe:
+	case providers.Airvpn, providers.Ivpn, providers.Mullvad, providers.Windscribe:
 		// EndpointPort is optional and can be 0
 		if *w.EndpointPort == 0 {
 			break // no custom endpoint port set
 		}
-		if helpers.IsOneOf(vpnProvider,
-			providers.Mullvad,
-			providers.Ovpn,
-		) {
+		if vpnProvider == providers.Mullvad {
 			break // no restriction on custom endpoint port value
 		}
 		var allowed []uint16
@@ -98,7 +92,7 @@ func (w WireguardSelection) validate(vpnProvider string) (err error) {
 	// Validate PublicKey
 	switch vpnProvider {
 	case providers.Fastestvpn, providers.Ivpn, providers.Mullvad,
-		providers.Ovpn, providers.Surfshark, providers.Windscribe:
+		providers.Surfshark, providers.Windscribe:
 		// public keys are baked in
 	case providers.Custom:
 		if w.PublicKey == "" {

internal/constants/providers/providers.go

@@ -15,7 +15,6 @@ const (
 	Ivpn                  = "ivpn"
 	Mullvad               = "mullvad"
 	Nordvpn               = "nordvpn"
-	Ovpn                  = "ovpn"
 	Perfectprivacy        = "perfect privacy"
 	Privado               = "privado"
 	PrivateInternetAccess = "private internet access"
@@ -44,7 +43,6 @@ func All() []string {
 		Ivpn,
 		Mullvad,
 		Nordvpn,
-		Ovpn,
 		Perfectprivacy,
 		Privado,
 		PrivateInternetAccess,

internal/firewall/interfaces.go

@@ -28,6 +28,8 @@ type firewallImpl interface { //nolint:interfacebloat
 	AcceptIpv6MulticastOutput(ctx context.Context, intf string) error
 	AcceptOutput(ctx context.Context, protocol, intf string,
 		ip netip.Addr, port uint16, remove bool) error
+	AcceptOutputFromIPPortToIPPort(ctx context.Context, protocol, intf string,
+		source, destination netip.AddrPort, remove bool) error
 	AcceptOutputFromIPToSubnet(ctx context.Context, intf string, assignedIP netip.Addr,
 		subnet netip.Prefix, remove bool) error
 	AcceptOutputThroughInterface(ctx context.Context, intf string, remove bool) error

internal/firewall/iptables/atomic.go

@@ -1,7 +1,6 @@
 package iptables
 
 import (
-	"bufio"
 	"context"
 	"fmt"
 	"os/exec"
@@ -97,25 +96,24 @@ func saveData(ctx context.Context, binary string) (data string, err error) {
 		}
 		return "", fmt.Errorf("running %s-save: %w", binary, err)
 	}
-	err = checkData(string(output))
-	if err != nil {
-		return "", fmt.Errorf("checking saved data: %w", err)
-	}
-	return string(output), nil
+	return filterData(output)
 }
 
-func checkData(data string) error {
-	scanner := bufio.NewScanner(strings.NewReader(data))
-	i := 0
-	for scanner.Scan() {
-		line := scanner.Text()
-		if strings.HasPrefix(line, "[unsupported") {
-			return fmt.Errorf("unsupported revision marker found in line %d: %s", i+1, line)
+func filterData(cmdOutput []byte) (filtered string, err error) {
+	lines := strings.Split(string(cmdOutput), "\n")
+	filteredLines := make([]string, 0, len(lines))
+	for _, line := range lines {
+		switch {
+		case strings.HasPrefix(line, ":DOCKER_OUTPUT"),
+			strings.HasPrefix(line, ":DOCKER_POSTROUTING"),
+			strings.HasPrefix(line, "-A DOCKER_OUTPUT"),
+			strings.HasPrefix(line, "-A DOCKER_POSTROUTING"):
+			// Do not touch (aka save and restore) NAT rules added by Docker
+			continue
+		case strings.Contains(line, "[unsupported revision]"):
+			return "", fmt.Errorf("mismatch container iptables-save and kernel: %s", line)
 		}
-		i++
+		filteredLines = append(filteredLines, line)
 	}
-	if scanner.Err() != nil {
-		return fmt.Errorf("scanning data: %w", scanner.Err())
-	}
-	return nil
+	return strings.Join(filteredLines, "\n"), nil
 }

internal/firewall/iptables/iptables.go

@@ -2,6 +2,7 @@ package iptables
 
 import (
 	"context"
+	"errors"
 	"fmt"
 	"io"
 	"net/netip"
@@ -177,6 +178,29 @@ func (c *Config) AcceptOutput(ctx context.Context,
 	return c.runIP6tablesInstruction(ctx, instruction)
 }
 
+func (c *Config) AcceptOutputFromIPPortToIPPort(ctx context.Context,
+	protocol, intf string, source, destination netip.AddrPort, remove bool,
+) error {
+	if source.Addr().BitLen() != destination.Addr().BitLen() {
+		return errors.New("source and destination address families do not match")
+	}
+
+	interfaceFlag := "-o " + intf
+	if intf == "*" { // all interfaces
+		interfaceFlag = ""
+	}
+
+	instruction := fmt.Sprintf("%s OUTPUT %s -s %s -d %s -p %s -m %s --sport %d --dport %d -j ACCEPT",
+		appendOrDelete(remove), interfaceFlag, source.Addr(), destination.Addr(),
+		protocol, protocol, source.Port(), destination.Port())
+	if destination.Addr().Is4() {
+		return c.runIptablesInstruction(ctx, instruction)
+	} else if c.ip6Tables == "" {
+		return fmt.Errorf("accept output from %s to %s: %s", source, destination, needIP6Tables)
+	}
+	return c.runIP6tablesInstruction(ctx, instruction)
+}
+
 // AcceptOutputFromIPToSubnet accepts outgoing traffic from sourceIP to destinationSubnet
 // on the interface intf. If intf is empty, it is set to "*" which means all interfaces.
 // If remove is true, the rule is removed instead of added.
@@ -278,7 +302,6 @@ func (c *Config) RedirectPort(ctx context.Context, intf string,
 			appendOrDelete(remove), interfaceFlag, destinationPort),
 	})
 	if err != nil {
-		restore(ctx) // just in case
 		errMessage := err.Error()
 		if strings.Contains(errMessage, "can't initialize ip6tables table `nat': Table does not exist") {
 			if !remove {
@@ -286,6 +309,7 @@ func (c *Config) RedirectPort(ctx context.Context, intf string,
 			}
 			return nil
 		}
+		restore(ctx)
 		return fmt.Errorf("redirecting IPv6 source port %d to destination port %d on interface %s: %w",
 			sourcePort, destinationPort, intf, err)
 	}

internal/firewall/wrappers.go

@@ -25,3 +25,10 @@ func (c *Config) AcceptOutput(ctx context.Context, protocol, intf string,
 ) error {
 	return c.impl.AcceptOutput(ctx, protocol, intf, ip, port, remove)
 }
+
+func (c *Config) AcceptOutputFromIPPortToIPPort(ctx context.Context,
+	protocol, intf string, source, destination netip.AddrPort, remove bool,
+) error {
+	return c.impl.AcceptOutputFromIPPortToIPPort(ctx, protocol, intf,
+		source, destination, remove)
+}

internal/models/server.go

@@ -34,11 +34,8 @@ type Server struct {
 	SecureCore  bool         `json:"secure_core,omitempty"`
 	Tor         bool         `json:"tor,omitempty"`
 	PortForward bool         `json:"port_forward,omitempty"`
-	Dedicated   bool         `json:"dedicated,omitempty"`
 	Keep        bool         `json:"keep,omitempty"`
 	IPs         []netip.Addr `json:"ips,omitempty"`
-	PortsTCP    []uint16     `json:"ports_tcp,omitempty"`
-	PortsUDP    []uint16     `json:"ports_udp,omitempty"`
 }
 
 func (s *Server) HasMinimumInformation() (err error) {

internal/openvpn/run.go

@@ -29,19 +29,16 @@ func (r *Runner) Run(ctx context.Context, errCh chan<- error, ready chan<- struc
 		return
 	}
 
-	streamCtx, streamCancel := context.WithCancel(context.Background())
 	streamDone := make(chan struct{})
-	go streamLines(streamCtx, streamDone, r.logger,
+	go streamLines(streamDone, r.logger,
 		stdoutLines, stderrLines, ready)
 
 	select {
 	case <-ctx.Done():
 		<-waitError
-		streamCancel()
 		<-streamDone
 		errCh <- ctx.Err()
 	case err := <-waitError:
-		streamCancel()
 		<-streamDone
 		errCh <- err
 	}

internal/openvpn/stream.go

@@ -1,26 +1,37 @@
 package openvpn
 
 import (
-	"context"
 	"strings"
 )
 
-func streamLines(ctx context.Context, done chan<- struct{},
+func streamLines(done chan<- struct{},
 	logger Logger, stdout, stderr <-chan string,
 	tunnelReady chan<- struct{},
 ) {
 	defer close(done)
 
-	var line string
-
 	for {
+		var line string
+		var ok bool
 		errLine := false
 		select {
-		case <-ctx.Done():
-			return
-		case line = <-stdout:
-		case line = <-stderr:
-			errLine = true
+		case line, ok = <-stdout:
+			if ok {
+				break
+			}
+			if stderr == nil {
+				return
+			}
+			stdout = nil
+		case line, ok = <-stderr:
+			if ok {
+				errLine = true
+				break
+			}
+			if stdout == nil {
+				return
+			}
+			stderr = nil
 		}
 		line, level := processLogLine(line)
 		if line == "" {

internal/portforward/service/command.go

@@ -15,7 +15,11 @@ func runCommand(ctx context.Context, cmder Cmder, logger Logger,
 	}
 	portsString := strings.Join(portStrings, ",")
 	commandString := strings.ReplaceAll(commandTemplate, "{{PORTS}}", portsString)
-	commandString = strings.ReplaceAll(commandString, "{{PORT}}", portStrings[0])
+	var firstPort string
+	if len(portStrings) > 0 {
+		firstPort = portStrings[0]
+	}
+	commandString = strings.ReplaceAll(commandString, "{{PORT}}", firstPort)
 	commandString = strings.ReplaceAll(commandString, "{{VPN_INTERFACE}}", vpnInterface)
 	return cmder.RunAndLog(ctx, commandString, logger)
 }

internal/portforward/service/service.go

@@ -2,6 +2,7 @@ package service
 
 import (
 	"context"
+	"errors"
 	"fmt"
 	"net/http"
 	"slices"
@@ -59,6 +60,10 @@ func (s *Service) SetPortsForwarded(ctx context.Context, ports []uint16) (err er
 	s.portMutex.Lock()
 	defer s.portMutex.Unlock()
 
+	if s.settings.PortForwarder != nil {
+		return errors.New("setting port forwarded at runtime is not supported with internally running port forwarding code")
+	}
+
 	slices.Sort(ports)
 	if slices.Equal(s.ports, ports) {
 		return nil
@@ -78,7 +83,5 @@ func (s *Service) SetPortsForwarded(ctx context.Context, ports []uint16) (err er
 		return fmt.Errorf("handling new ports: %w", err)
 	}
 
-	s.logger.Info("updated: " + portsToString(s.ports))
-
 	return nil
 }

internal/portforward/service/settings.go

@@ -88,7 +88,7 @@ func (s *Settings) Validate(forStartup bool) (err error) {
 			return errors.New("password not set")
 		}
 	case providers.Protonvpn:
-		const maxPortsCount = 4
+		const maxPortsCount = 5
 		if s.PortsCount > maxPortsCount {
 			return fmt.Errorf("ports count too high: %d > %d", s.PortsCount, maxPortsCount)
 		}

internal/portforward/service/start.go

@@ -92,13 +92,9 @@ func (s *Service) onNewPorts(ctx context.Context, internalToExternalPorts map[ui
 	s.logger.Info(portPairsToString(internalToExternalPorts))
 
 	externalPorts := slices.Collect(maps.Values(internalToExternalPorts))
-	autoRedirectionNeeded := false
 	externalToInternalPorts := make(map[uint16]uint16, len(internalToExternalPorts))
 	for internal, external := range internalToExternalPorts {
 		externalToInternalPorts[external] = internal
-		if internal != external {
-			autoRedirectionNeeded = true
-		}
 	}
 	slices.Sort(externalPorts)
 	userRedirectionEnabled := !slices.Equal(s.settings.ListeningPorts, []uint16{0})
@@ -109,23 +105,21 @@ func (s *Service) onNewPorts(ctx context.Context, internalToExternalPorts map[ui
 			return fmt.Errorf("allowing port in firewall: %w", err)
 		}
 
-		var sourcePort, destinationPort uint16
+		var destinationPort uint16
 		switch {
 		case userRedirectionEnabled: // precedence over auto redirection
-			sourcePort = externalToInternalPorts[port]
 			destinationPort = s.settings.ListeningPorts[i]
-		case autoRedirectionNeeded:
-			sourcePort = externalToInternalPorts[port]
+		case port != internalPort: // auto redirection needed, source and destination ports differ
 			destinationPort = port
 		default:
 			// No redirection needed, source and destination ports are the same.
 			continue
 		}
 
-		err = s.portAllower.RedirectPort(ctx, s.settings.Interface, sourcePort, destinationPort)
+		err = s.portAllower.RedirectPort(ctx, s.settings.Interface, internalPort, destinationPort)
 		if err != nil {
 			return fmt.Errorf("redirecting port %d to %d in firewall: %w",
-				sourcePort, destinationPort, err)
+				internalPort, destinationPort, err)
 		}
 	}
 

internal/provider/custom/openvpnconf.go

@@ -6,6 +6,7 @@ import (
 	"strings"
 
 	"github.com/qdm12/gluetun/internal/configuration/settings"
+	"github.com/qdm12/gluetun/internal/constants"
 	"github.com/qdm12/gluetun/internal/constants/openvpn"
 	"github.com/qdm12/gluetun/internal/models"
 	"github.com/qdm12/gluetun/internal/provider/utils"
@@ -65,7 +66,11 @@ func modifyConfig(lines []string, connection models.Connection,
 	}
 
 	// Add values
-	modified = append(modified, "proto "+connection.Protocol)
+	protocol := connection.Protocol
+	if protocol == constants.TCP {
+		protocol = "tcp-client"
+	}
+	modified = append(modified, "proto "+protocol)
 	modified = append(modified, fmt.Sprintf("remote %s %d", connection.IP, connection.Port))
 	modified = append(modified, "dev "+settings.Interface)
 	modified = append(modified, "mute-replay-warnings")

internal/provider/ovpn/connection.go

@@ -1,15 +0,0 @@
-package ovpn
-
-import (
-	"github.com/qdm12/gluetun/internal/configuration/settings"
-	"github.com/qdm12/gluetun/internal/models"
-	"github.com/qdm12/gluetun/internal/provider/utils"
-)
-
-func (p *Provider) GetConnection(selection settings.ServerSelection, ipv6Supported bool) (
-	connection models.Connection, err error,
-) {
-	defaults := utils.NewConnectionDefaults(443, 1194, 9929) //nolint:mnd
-	return utils.GetConnection(p.Name(),
-		p.storage, selection, defaults, ipv6Supported, p.connPicker)
-}

internal/provider/ovpn/connection_test.go

@@ -1,126 +0,0 @@
-package ovpn
-
-import (
-	"errors"
-	"net/http"
-	"net/netip"
-	"testing"
-
-	"github.com/golang/mock/gomock"
-	"github.com/qdm12/gluetun/internal/configuration/settings"
-	"github.com/qdm12/gluetun/internal/constants"
-	"github.com/qdm12/gluetun/internal/constants/providers"
-	"github.com/qdm12/gluetun/internal/constants/vpn"
-	"github.com/qdm12/gluetun/internal/models"
-	"github.com/qdm12/gluetun/internal/provider/common"
-	"github.com/stretchr/testify/assert"
-)
-
-func Test_Provider_GetConnection(t *testing.T) {
-	t.Parallel()
-
-	const provider = providers.Ovpn
-
-	errTest := errors.New("test error")
-
-	testCases := map[string]struct {
-		filteredServers []models.Server
-		storageErr      error
-		selection       settings.ServerSelection
-		ipv6Supported   bool
-		connection      models.Connection
-		errWrapped      error
-		errMessage      string
-	}{
-		"error": {
-			storageErr: errTest,
-			errWrapped: errTest,
-			errMessage: "filtering servers: test error",
-		},
-		"default_openvpn_tcp_port": {
-			filteredServers: []models.Server{
-				{IPs: []netip.Addr{netip.AddrFrom4([4]byte{1, 1, 1, 1})}},
-			},
-			selection: settings.ServerSelection{
-				OpenVPN: settings.OpenVPNSelection{
-					Protocol: constants.TCP,
-				},
-			}.WithDefaults(provider),
-			connection: models.Connection{
-				Type:     vpn.OpenVPN,
-				IP:       netip.AddrFrom4([4]byte{1, 1, 1, 1}),
-				Port:     443,
-				Protocol: constants.TCP,
-			},
-		},
-		"default_openvpn_udp_port": {
-			filteredServers: []models.Server{
-				{IPs: []netip.Addr{netip.AddrFrom4([4]byte{1, 1, 1, 1})}},
-			},
-			selection: settings.ServerSelection{
-				OpenVPN: settings.OpenVPNSelection{
-					Protocol: constants.UDP,
-				},
-			}.WithDefaults(provider),
-			connection: models.Connection{
-				Type:     vpn.OpenVPN,
-				IP:       netip.AddrFrom4([4]byte{1, 1, 1, 1}),
-				Port:     1194,
-				Protocol: constants.UDP,
-			},
-		},
-		"default_wireguard_port": {
-			filteredServers: []models.Server{
-				{IPs: []netip.Addr{netip.AddrFrom4([4]byte{1, 1, 1, 1})}, WgPubKey: "x"},
-			},
-			selection: settings.ServerSelection{
-				VPN: vpn.Wireguard,
-			}.WithDefaults(provider),
-			connection: models.Connection{
-				Type:     vpn.Wireguard,
-				IP:       netip.AddrFrom4([4]byte{1, 1, 1, 1}),
-				Port:     9929,
-				Protocol: constants.UDP,
-				PubKey:   "x",
-			},
-		},
-		"default_multihop_port": {
-			filteredServers: []models.Server{
-				{IPs: []netip.Addr{netip.AddrFrom4([4]byte{1, 1, 1, 1})}, WgPubKey: "x", PortsUDP: []uint16{30044}},
-			},
-			selection: settings.ServerSelection{
-				VPN: vpn.Wireguard,
-			}.WithDefaults(provider),
-			connection: models.Connection{
-				Type:     vpn.Wireguard,
-				IP:       netip.AddrFrom4([4]byte{1, 1, 1, 1}),
-				Port:     30044,
-				Protocol: constants.UDP,
-				PubKey:   "x",
-			},
-		},
-	}
-
-	for name, testCase := range testCases {
-		t.Run(name, func(t *testing.T) {
-			t.Parallel()
-			ctrl := gomock.NewController(t)
-
-			storage := common.NewMockStorage(ctrl)
-			storage.EXPECT().FilterServers(provider, testCase.selection).
-				Return(testCase.filteredServers, testCase.storageErr)
-
-			client := (*http.Client)(nil)
-			provider := New(storage, client)
-
-			connection, err := provider.GetConnection(testCase.selection, testCase.ipv6Supported)
-
-			assert.ErrorIs(t, err, testCase.errWrapped)
-			if testCase.errWrapped != nil {
-				assert.EqualError(t, err, testCase.errMessage)
-			}
-
-			assert.Equal(t, testCase.connection, connection)
-		})
-	}
-}

internal/provider/ovpn/openvpnconf.go

@@ -1,38 +0,0 @@
-package ovpn
-
-import (
-	"strings"
-
-	"github.com/qdm12/gluetun/internal/configuration/settings"
-	"github.com/qdm12/gluetun/internal/constants/openvpn"
-	"github.com/qdm12/gluetun/internal/models"
-	"github.com/qdm12/gluetun/internal/provider/utils"
-)
-
-func (p *Provider) OpenVPNConfig(connection models.Connection,
-	settings settings.OpenVPN, ipv6Supported bool,
-) (lines []string) {
-	providerSettings := utils.OpenVPNProviderSettings{
-		AuthUserPass:  true,
-		RemoteCertTLS: true,
-		Ciphers: []string{
-			openvpn.AES256gcm,
-			openvpn.AES256cbc,
-			openvpn.AES128gcm,
-			openvpn.Chacha20Poly1305,
-		},
-		CAs: []string{
-			"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", //nolint:lll
-		},
-		TLSAuth:      "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", //nolint:lll
-		KeyDirection: "1",
-	}
-
-	if strings.HasSuffix(connection.Hostname, "singapore.ovpn.com") {
-		providerSettings.TLSCrypt = providerSettings.TLSAuth
-		providerSettings.TLSAuth = ""
-		providerSettings.KeyDirection = ""
-	}
-
-	return utils.OpenVPNConfig(providerSettings, connection, settings, ipv6Supported)
-}

internal/provider/ovpn/provider.go

@@ -1,28 +0,0 @@
-package ovpn
-
-import (
-	"net/http"
-
-	"github.com/qdm12/gluetun/internal/constants/providers"
-	"github.com/qdm12/gluetun/internal/provider/common"
-	"github.com/qdm12/gluetun/internal/provider/ovpn/updater"
-	"github.com/qdm12/gluetun/internal/provider/utils"
-)
-
-type Provider struct {
-	storage    common.Storage
-	connPicker *utils.ConnectionPicker
-	common.Fetcher
-}
-
-func New(storage common.Storage, client *http.Client) *Provider {
-	return &Provider{
-		storage:    storage,
-		connPicker: utils.NewConnectionPicker(),
-		Fetcher:    updater.New(client),
-	}
-}
-
-func (p *Provider) Name() string {
-	return providers.Ovpn
-}

internal/provider/ovpn/updater/api.go

@@ -1,153 +0,0 @@
-package updater
-
-import (
-	"context"
-	"encoding/json"
-	"errors"
-	"fmt"
-	"net/http"
-	"net/netip"
-	"strings"
-)
-
-type apiData struct {
-	Success     bool            `json:"success"`
-	DataCenters []apiDataCenter `json:"datacenters"`
-}
-
-type apiDataCenter struct {
-	City        string      `json:"city"`
-	CountryName string      `json:"country_name"`
-	Servers     []apiServer `json:"servers"`
-}
-
-type apiServer struct {
-	IP     netip.Addr `json:"ip"`
-	Ptr    string     `json:"ptr"` // hostname
-	Online bool       `json:"online"`
-	// PublicKey is for the Standard Shared Entry Point
-	PublicKey string `json:"public_key"`
-	// PublicKeyIPv4 is for the Public / Dedicated IP Entry Point
-	PublicKeyIPv4         string   `json:"public_key_ipv4"`
-	WireguardPorts        []uint16 `json:"wireguard_ports"`
-	MultiHopOpenvpnPort   uint16   `json:"multihop_openvpn_port"`
-	MultiHopWireguardPort uint16   `json:"multihop_wireguard_port"`
-}
-
-func fetchAPI(ctx context.Context, client *http.Client) (
-	data apiData, err error,
-) {
-	const url = "https://www.ovpn.com/v2/api/client/entry"
-
-	request, err := http.NewRequestWithContext(ctx, http.MethodGet, url, nil)
-	if err != nil {
-		return data, err
-	}
-
-	response, err := client.Do(request)
-	if err != nil {
-		return data, err
-	}
-
-	if response.StatusCode != http.StatusOK {
-		_ = response.Body.Close()
-		return data, fmt.Errorf("HTTP response status code is not OK: %d %s",
-			response.StatusCode, response.Status)
-	}
-
-	decoder := json.NewDecoder(response.Body)
-	err = decoder.Decode(&data)
-	if err != nil {
-		_ = response.Body.Close()
-		return data, fmt.Errorf("decoding response body: %w", err)
-	}
-
-	err = response.Body.Close()
-	if err != nil {
-		return data, fmt.Errorf("closing response body: %w", err)
-	}
-
-	return data, nil
-}
-
-func (a *apiDataCenter) validate() (err error) {
-	conditionalErrors := []conditionalError{
-		{err: "city is not set", condition: a.City == ""},
-		{err: "country name is not set", condition: a.CountryName == ""},
-		{err: "servers array is not set", condition: len(a.Servers) == 0},
-	}
-	err = collectErrors(conditionalErrors)
-	if err != nil {
-		var dataCenterSetFields []string
-		if a.CountryName != "" {
-			dataCenterSetFields = append(dataCenterSetFields, a.CountryName)
-		}
-		if a.City != "" {
-			dataCenterSetFields = append(dataCenterSetFields, a.City)
-		}
-		if len(dataCenterSetFields) == 0 {
-			return err
-		}
-		return fmt.Errorf("data center %s: %w",
-			strings.Join(dataCenterSetFields, ", "), err)
-	}
-
-	for i, server := range a.Servers {
-		err = server.validate()
-		if err != nil {
-			return fmt.Errorf("datacenter %s, %s: server %d of %d: %w",
-				a.CountryName, a.City, i+1, len(a.Servers), err)
-		}
-	}
-
-	return nil
-}
-
-func (a *apiServer) validate() (err error) {
-	const defaultWireguardPort = 9929
-	conditionalErrors := []conditionalError{
-		{err: "ip address is not set", condition: !a.IP.IsValid()},
-		{err: "hostname field is not set", condition: a.Ptr == ""},
-		{err: "public key field is not set", condition: a.PublicKey == ""},
-		{err: "public key IPv4 field is not set", condition: a.PublicKeyIPv4 == ""},
-		{err: "wireguard ports array is not set", condition: len(a.WireguardPorts) == 0},
-		{
-			err:       "wireguard port is not the default 9929",
-			condition: len(a.WireguardPorts) != 1 || a.WireguardPorts[0] != defaultWireguardPort,
-		},
-		{err: "multihop OpenVPN port is not set", condition: a.MultiHopOpenvpnPort == 0},
-		{err: "multihop WireGuard port is not set", condition: a.MultiHopWireguardPort == 0},
-	}
-	err = collectErrors(conditionalErrors)
-	switch {
-	case err == nil:
-		return nil
-	case a.Ptr != "":
-		return fmt.Errorf("server %s: %w", a.Ptr, err)
-	case a.IP.IsValid():
-		return fmt.Errorf("server %s: %w", a.IP.String(), err)
-	default:
-		return err
-	}
-}
-
-type conditionalError struct {
-	err       string
-	condition bool
-}
-
-func collectErrors(conditionalErrors []conditionalError) (err error) {
-	errs := make([]string, 0, len(conditionalErrors))
-	for _, conditionalError := range conditionalErrors {
-		if !conditionalError.condition {
-			continue
-		}
-		errs = append(errs, conditionalError.err)
-	}
-
-	if len(errs) == 0 {
-		return nil
-	}
-
-	return errors.New(strings.Join(errs, "; "))
-}

internal/provider/ovpn/updater/api_test.go

@@ -1,118 +0,0 @@
-package updater
-
-import (
-	"context"
-	"errors"
-	"io"
-	"net/http"
-	"net/netip"
-	"strings"
-	"testing"
-
-	"github.com/stretchr/testify/assert"
-	"github.com/stretchr/testify/require"
-)
-
-func Test_fetchAPI(t *testing.T) {
-	t.Parallel()
-
-	testCases := map[string]struct {
-		responseStatus int
-		responseBody   io.ReadCloser
-		data           apiData
-		err            error
-	}{
-		"http response status not ok": {
-			responseStatus: http.StatusNoContent,
-			err:            errors.New("HTTP response status code is not OK: 204 No Content"),
-		},
-		"nil body": {
-			responseStatus: http.StatusOK,
-			err:            errors.New("decoding response body: EOF"),
-		},
-		"no server": {
-			responseStatus: http.StatusOK,
-			responseBody:   io.NopCloser(strings.NewReader(`{}`)),
-		},
-		"success": {
-			responseStatus: http.StatusOK,
-			responseBody: io.NopCloser(strings.NewReader(`{
-		  "success": true,
-		  "datacenters": [
-		    {
-		      "slug": "vienna",
-		      "city": "Vienna",
-		      "country": "AT",
-		      "country_name": "Austria",
-		      "pools": [
-		        "pool-1.prd.at.vienna.ovpn.com"
-		      ],
-		      "ping_address": "37.120.212.227",
-		      "servers": [
-		        {
-		          "ip": "37.120.212.227",
-		          "ptr": "vpn44.prd.vienna.ovpn.com",
-		          "name": "VPN44 - Vienna",
-		          "online": true,
-		          "load": 8,
-		          "public_key": "r83LIc0Q2F8s3dY9x5y17Yz8wTADJc7giW1t5eSmoXc=",
-		          "public_key_ipv4": "wFbSRyjSXBmkjJodlqz7DoYn3WNDPYFUIXyIUS2QU2A=",
-		          "wireguard_ports": [
-		            9929
-		          ],
-		          "multihop_openvpn_port": 20044,
-		          "multihop_wireguard_port": 30044
-		        }
-		      ]
-		    }
-		  ]
-		}`)),
-			data: apiData{
-				Success: true,
-				DataCenters: []apiDataCenter{
-					{CountryName: "Austria", City: "Vienna", Servers: []apiServer{
-						{
-							IP:                    netip.MustParseAddr("37.120.212.227"),
-							Ptr:                   "vpn44.prd.vienna.ovpn.com",
-							Online:                true,
-							PublicKey:             "r83LIc0Q2F8s3dY9x5y17Yz8wTADJc7giW1t5eSmoXc=",
-							PublicKeyIPv4:         "wFbSRyjSXBmkjJodlqz7DoYn3WNDPYFUIXyIUS2QU2A=",
-							WireguardPorts:        []uint16{9929},
-							MultiHopOpenvpnPort:   20044,
-							MultiHopWireguardPort: 30044,
-						},
-					}},
-				},
-			},
-		},
-	}
-	for name, testCase := range testCases {
-		t.Run(name, func(t *testing.T) {
-			t.Parallel()
-
-			ctx := context.Background()
-
-			client := &http.Client{
-				Transport: roundTripFunc(func(r *http.Request) (*http.Response, error) {
-					assert.Equal(t, http.MethodGet, r.Method)
-					assert.Equal(t, r.URL.String(), "https://www.ovpn.com/v2/api/client/entry")
-					return &http.Response{
-						StatusCode: testCase.responseStatus,
-						Status:     http.StatusText(testCase.responseStatus),
-						Body:       testCase.responseBody,
-					}, nil
-				}),
-			}
-
-			data, err := fetchAPI(ctx, client)
-
-			assert.Equal(t, testCase.data, data)
-			if testCase.err != nil {
-				require.Error(t, err)
-				assert.Equal(t, testCase.err.Error(), err.Error())
-			} else {
-				assert.NoError(t, err)
-			}
-		})
-	}
-}

internal/provider/ovpn/updater/roundtrip_test.go

@@ -1,9 +0,0 @@
-package updater
-
-import "net/http"
-
-type roundTripFunc func(r *http.Request) (*http.Response, error)
-
-func (f roundTripFunc) RoundTrip(r *http.Request) (*http.Response, error) {
-	return f(r)
-}

internal/provider/ovpn/updater/servers.go

@@ -1,82 +0,0 @@
-package updater
-
-import (
-	"context"
-	"errors"
-	"fmt"
-	"net/netip"
-	"sort"
-
-	"github.com/qdm12/gluetun/internal/constants/vpn"
-	"github.com/qdm12/gluetun/internal/models"
-	"github.com/qdm12/gluetun/internal/provider/common"
-)
-
-func (u *Updater) FetchServers(ctx context.Context, minServers int) (
-	servers []models.Server, err error,
-) {
-	data, err := fetchAPI(ctx, u.client)
-	if err != nil {
-		return nil, fmt.Errorf("fetching API: %w", err)
-	} else if !data.Success {
-		return nil, errors.New("response success field is false")
-	}
-
-	for dataCenterIndex, dataCenter := range data.DataCenters {
-		err = dataCenter.validate()
-		if err != nil {
-			return nil, fmt.Errorf("validating data center %d of %d: %w",
-				dataCenterIndex+1, len(data.DataCenters), err)
-		}
-
-		for _, apiServer := range dataCenter.Servers {
-			if !apiServer.Online {
-				continue
-			}
-
-			baseServer := models.Server{
-				Country:  dataCenter.CountryName,
-				City:     dataCenter.City,
-				Hostname: apiServer.Ptr,
-				IPs:      []netip.Addr{apiServer.IP},
-			}
-			openVPNServer := baseServer
-			openVPNServer.VPN = vpn.OpenVPN
-			openVPNServer.TCP = true
-			openVPNServer.UDP = true
-			multiHopOpenVPNServer := openVPNServer
-			multiHopOpenVPNServer.MultiHop = true
-			multiHopOpenVPNServer.PortsTCP = []uint16{apiServer.MultiHopOpenvpnPort}
-			multiHopOpenVPNServer.PortsUDP = []uint16{apiServer.MultiHopOpenvpnPort}
-			servers = append(servers, openVPNServer, multiHopOpenVPNServer)
-
-			wireguardServer := baseServer
-			wireguardServer.VPN = vpn.Wireguard
-			wireguardServer.WgPubKey = apiServer.PublicKey
-			multiHopWireguardServer := wireguardServer
-			multiHopWireguardServer.MultiHop = true
-			multiHopWireguardServer.PortsUDP = []uint16{apiServer.MultiHopWireguardPort}
-			dedicatedWireguardServer := wireguardServer
-			dedicatedWireguardServer.WgPubKey = apiServer.PublicKeyIPv4
-			dedicatedWireguardServer.Dedicated = true
-			dedicatedMultiHopWireguardServer := multiHopWireguardServer
-			dedicatedMultiHopWireguardServer.WgPubKey = apiServer.PublicKeyIPv4
-			dedicatedMultiHopWireguardServer.Dedicated = true
-			servers = append(servers,
-				wireguardServer,
-				multiHopWireguardServer,
-				dedicatedWireguardServer,
-				dedicatedMultiHopWireguardServer,
-			)
-		}
-	}
-
-	if len(servers) < minServers {
-		return nil, fmt.Errorf("%w: %d and expected at least %d",
-			common.ErrNotEnoughServers, len(servers), minServers)
-	}
-
-	sort.Sort(models.SortableServers(servers))
-
-	return servers, nil
-}

internal/provider/ovpn/updater/servers_test.go

@@ -1,228 +0,0 @@
-package updater
-
-import (
-	"context"
-	"io"
-	"net/http"
-	"net/netip"
-	"strings"
-	"testing"
-
-	"github.com/qdm12/gluetun/internal/constants/vpn"
-	"github.com/qdm12/gluetun/internal/models"
-	"github.com/qdm12/gluetun/internal/provider/common"
-	"github.com/stretchr/testify/assert"
-)
-
-func Test_Updater_FetchServers(t *testing.T) {
-	t.Parallel()
-
-	testCases := map[string]struct {
-		// Inputs
-		minServers int
-
-		// From API
-		responseStatus int
-		responseBody   string
-
-		// Output
-		servers    []models.Server
-		errWrapped error
-		errMessage string
-	}{
-		"http_response_error": {
-			responseStatus: http.StatusNoContent,
-			errMessage:     "fetching API: HTTP response status code is not OK: 204 No Content",
-		},
-		"success_field_false": {
-			responseStatus: http.StatusOK,
-			responseBody:   `{"success": false}`,
-			errMessage:     "response success field is false",
-		},
-		"validation_failed": {
-			responseStatus: http.StatusOK,
-			responseBody: `{
-  "success": true,
-  "datacenters": [
-    {
-      "city": "Vienna",
-      "servers": [
-        {}
-      ]
-    }
-  ]
-}`,
-			errMessage: "validating data center 1 of 1: data center Vienna: country name is not set",
-		},
-		"not_enough_servers": {
-			minServers:     7,
-			responseStatus: http.StatusOK,
-			responseBody: `{
-  "success": true,
-  "datacenters": [
-    {
-      "city": "Vienna",
-      "country_name": "Austria",
-      "servers": [
-        {
-          "ip": "37.120.212.227",
-          "ptr": "vpn44.prd.vienna.ovpn.com",
-          "online": true,
-          "public_key": "r83LIc0Q2F8s3dY9x5y17Yz8wTADJc7giW1t5eSmoXc=",
-					"public_key_ipv4": "wFbSRyjSXBmkjJodlqz7DoYn3WNDPYFUIXyIUS2QU2A=",
-          "wireguard_ports": [9929],
-          "multihop_openvpn_port": 20044,
-          "multihop_wireguard_port": 30044
-        }
-      ]
-    }
-  ]
-}`,
-			errWrapped: common.ErrNotEnoughServers,
-			// Wireguard + dedicated Wireguard + Wireguard multi-hop +
-			// dedicated Wireguard multi-hop + OpenVPN + OpenVPN multi-hop
-			errMessage: "not enough servers found: 6 and expected at least 7",
-		},
-		"success": {
-			minServers: 4,
-			responseBody: `{
-  "success": true,
-  "datacenters": [
-    {
-      "slug": "vienna",
-      "city": "Vienna",
-      "country": "AT",
-      "country_name": "Austria",
-      "pools": [
-        "pool-1.prd.at.vienna.ovpn.com"
-      ],
-      "ping_address": "37.120.212.227",
-      "servers": [
-        {
-          "ip": "37.120.212.227",
-          "ptr": "vpn44.prd.vienna.ovpn.com",
-          "name": "VPN44 - Vienna",
-          "online": true,
-          "load": 8,
-          "public_key": "r83LIc0Q2F8s3dY9x5y17Yz8wTADJc7giW1t5eSmoXc=",
-          "public_key_ipv4": "wFbSRyjSXBmkjJodlqz7DoYn3WNDPYFUIXyIUS2QU2A=",
-          "wireguard_ports": [
-            9929
-          ],
-          "multihop_openvpn_port": 20044,
-          "multihop_wireguard_port": 30044
-        },
-        {
-          "ip": "37.120.212.228",
-          "ptr": "vpn45.prd.vienna.ovpn.com",
-          "online": false,
-          "public_key": "r93LIc0Q2F8s3dY9x5y17Yz8wTADJc7giW1t5eSmoXc=",
-					"public_key_ipv4": "wGbSRyjSXBmkjJodlqz7DoYn3WNDPYFUIXyIUS2QU2A=",
-          "wireguard_ports": [9929],
-          "multihop_openvpn_port": 20045,
-          "multihop_wireguard_port": 30045
-        }
-      ]
-    }
-  ]
-}`,
-			responseStatus: http.StatusOK,
-			servers: []models.Server{
-				{
-					Country:  "Austria",
-					City:     "Vienna",
-					Hostname: "vpn44.prd.vienna.ovpn.com",
-					IPs:      []netip.Addr{netip.MustParseAddr("37.120.212.227")},
-					VPN:      vpn.OpenVPN,
-					UDP:      true,
-					TCP:      true,
-				},
-				{
-					Country:  "Austria",
-					City:     "Vienna",
-					Hostname: "vpn44.prd.vienna.ovpn.com",
-					IPs:      []netip.Addr{netip.MustParseAddr("37.120.212.227")},
-					VPN:      vpn.OpenVPN,
-					UDP:      true,
-					TCP:      true,
-					MultiHop: true,
-					PortsTCP: []uint16{20044},
-					PortsUDP: []uint16{20044},
-				},
-				{
-					Country:  "Austria",
-					City:     "Vienna",
-					Hostname: "vpn44.prd.vienna.ovpn.com",
-					IPs:      []netip.Addr{netip.MustParseAddr("37.120.212.227")},
-					VPN:      vpn.Wireguard,
-					WgPubKey: "r83LIc0Q2F8s3dY9x5y17Yz8wTADJc7giW1t5eSmoXc=",
-				},
-				{
-					Country:  "Austria",
-					City:     "Vienna",
-					Hostname: "vpn44.prd.vienna.ovpn.com",
-					IPs:      []netip.Addr{netip.MustParseAddr("37.120.212.227")},
-					VPN:      vpn.Wireguard,
-					WgPubKey: "r83LIc0Q2F8s3dY9x5y17Yz8wTADJc7giW1t5eSmoXc=",
-					MultiHop: true,
-					PortsUDP: []uint16{30044},
-				},
-				{
-					Country:   "Austria",
-					City:      "Vienna",
-					Hostname:  "vpn44.prd.vienna.ovpn.com",
-					IPs:       []netip.Addr{netip.MustParseAddr("37.120.212.227")},
-					VPN:       vpn.Wireguard,
-					WgPubKey:  "wFbSRyjSXBmkjJodlqz7DoYn3WNDPYFUIXyIUS2QU2A=",
-					Dedicated: true,
-				},
-				{
-					Country:   "Austria",
-					City:      "Vienna",
-					Hostname:  "vpn44.prd.vienna.ovpn.com",
-					IPs:       []netip.Addr{netip.MustParseAddr("37.120.212.227")},
-					VPN:       vpn.Wireguard,
-					WgPubKey:  "wFbSRyjSXBmkjJodlqz7DoYn3WNDPYFUIXyIUS2QU2A=",
-					MultiHop:  true,
-					Dedicated: true,
-					PortsUDP:  []uint16{30044},
-				},
-			},
-		},
-	}
-	for name, testCase := range testCases {
-		t.Run(name, func(t *testing.T) {
-			t.Parallel()
-
-			ctx := context.Background()
-
-			client := &http.Client{
-				Transport: roundTripFunc(func(r *http.Request) (*http.Response, error) {
-					assert.Equal(t, http.MethodGet, r.Method)
-					assert.Equal(t, r.URL.String(), "https://www.ovpn.com/v2/api/client/entry")
-					return &http.Response{
-						StatusCode: testCase.responseStatus,
-						Status:     http.StatusText(testCase.responseStatus),
-						Body:       io.NopCloser(strings.NewReader(testCase.responseBody)),
-					}, nil
-				}),
-			}
-
-			updater := &Updater{
-				client: client,
-			}
-
-			servers, err := updater.FetchServers(ctx, testCase.minServers)
-
-			assert.Equal(t, testCase.servers, servers)
-			if testCase.errMessage == "" {
-				assert.NoError(t, err)
-			} else {
-				assert.Contains(t, err.Error(), testCase.errMessage)
-			}
-			if testCase.errWrapped != nil {
-				assert.ErrorIs(t, err, testCase.errWrapped)
-			}
-		})
-	}
-}

internal/provider/ovpn/updater/updater.go

@@ -1,15 +0,0 @@
-package updater
-
-import (
-	"net/http"
-)
-
-type Updater struct {
-	client *http.Client
-}
-
-func New(client *http.Client) *Updater {
-	return &Updater{
-		client: client,
-	}
-}

internal/provider/protonvpn/portforward.go

@@ -5,6 +5,7 @@ import (
 	"errors"
 	"fmt"
 	"maps"
+	"net/netip"
 	"strings"
 	"time"
 
@@ -12,14 +13,14 @@ import (
 	"github.com/qdm12/gluetun/internal/provider/utils"
 )
 
-const nonSymmetricPortStart uint16 = 56789
-
 // PortForward obtains a VPN server side port forwarded from ProtonVPN gateway.
 func (p *Provider) PortForward(ctx context.Context, objects utils.PortForwardObjects) (
 	internalToExternalPorts map[uint16]uint16, err error,
 ) {
 	if !objects.CanPortForward {
 		return nil, errors.New("server does not support port forwarding")
+	} else if objects.PortsCount == 0 {
+		return nil, nil //nolint:nilnil
 	}
 
 	client := natpmp.New()
@@ -39,38 +40,75 @@ func (p *Provider) PortForward(ctx context.Context, objects utils.PortForwardObj
 	logger := objects.Logger
 
 	logger.Debug("gateway external IPv4 address is " + externalIPv4Address.String())
-	const externalPort = 0
-	const lifetime = 60 * time.Second
 
 	p.internalToExternalPorts = make(map[uint16]uint16, objects.PortsCount)
-	for i := range objects.PortsCount {
-		internalPort := nonSymmetricPortStart + i
-		protoToInternalPort := map[string]uint16{
-			"udp": 0,
-			"tcp": 0,
-		}
-		protoToExternalPort := maps.Clone(protoToInternalPort)
-		for protocol := range protoToExternalPort {
-			_, assignedInternalPort, assignedExternalPort, assignedLifetime, err := client.AddPortMapping(
-				ctx, objects.Gateway, protocol, internalPort, externalPort, lifetime)
-			if err != nil {
-				return nil, fmt.Errorf("adding %d/%d %s port mapping: %w",
-					i+1, objects.PortsCount, strings.ToUpper(protocol), err)
-			}
-			checkLifetime(logger, strings.ToUpper(protocol), lifetime, assignedLifetime)
-			checkInternalPort(logger, internalPort, assignedInternalPort)
-			protoToInternalPort[protocol] = assignedInternalPort
-			protoToExternalPort[protocol] = assignedExternalPort
-		}
+	const lifetime = 60 * time.Second
 
-		checkInternalPorts(logger, protoToInternalPort["udp"], protoToInternalPort["tcp"])
-		checkExternalPorts(logger, protoToExternalPort["udp"], protoToExternalPort["tcp"])
-		p.internalToExternalPorts[protoToInternalPort["tcp"]] = protoToExternalPort["tcp"]
+	// Only one port can be a symmetric mapping
+	const internalPort, externalPort = 0, 1
+	_, assignedExternalPort, err := addPortMappingTCPUDP(ctx,
+		client, logger, objects.Gateway, internalPort, externalPort, lifetime)
+	// Note the returned assignedInternalPort is always 0 in this case
+	if err != nil {
+		return nil, fmt.Errorf("adding first port mapping: %w", err)
+	}
+	p.internalToExternalPorts[assignedExternalPort] = assignedExternalPort
+
+	// Extra ports must be non-symmetric, meaning that the internal port is
+	// different from the external port.
+	const nonSymmetricPortStart = uint16(56789)
+	nonSymmetricPortStartMinusOne := nonSymmetricPortStart - 1
+	if _, ok := p.internalToExternalPorts[nonSymmetricPortStart]; ok {
+		nonSymmetricPortStartMinusOne++
+	}
+	for i := uint16(1); i < objects.PortsCount; i++ {
+		internalPort := nonSymmetricPortStartMinusOne + i
+		const externalPort = 0
+		assignedInternalPort, assignedExternalPort, err := addPortMappingTCPUDP(ctx,
+			client, logger, objects.Gateway, internalPort, externalPort, lifetime)
+		if err != nil {
+			return nil, fmt.Errorf("adding %d/%d port mapping: %w", i+1, objects.PortsCount, err)
+		}
+		p.internalToExternalPorts[assignedInternalPort] = assignedExternalPort
 	}
 
 	return maps.Clone(p.internalToExternalPorts), nil
 }
 
+func addPortMappingTCPUDP(ctx context.Context, client *natpmp.Client, logger utils.Logger,
+	gateway netip.Addr, internalPort, externalPort uint16, lifetime time.Duration,
+) (assignedInternalPort, assignedExternalPort uint16, err error) {
+	var assignedLifetime time.Duration
+	protocolToExternalPort := map[string]uint16{
+		"tcp": 0,
+		"udp": 0,
+	}
+	for _, protocol := range [...]string{"udp", "tcp"} {
+		protocolStr := strings.ToUpper(protocol)
+		_, assignedInternalPort, assignedExternalPort, assignedLifetime, err = client.AddPortMapping(
+			ctx, gateway, protocol, internalPort, externalPort, lifetime)
+		if err != nil {
+			return 0, 0, fmt.Errorf("adding %s port mapping: %w", protocolStr, err)
+		}
+		protocolToExternalPort[protocol] = assignedExternalPort
+		checkLifetime(logger, protocolStr, lifetime, assignedLifetime)
+		if internalPort != assignedInternalPort {
+			return 0, 0, fmt.Errorf("%s internal port requested as %d but received %d",
+				protocolStr, internalPort, assignedInternalPort)
+		} else if externalPort != 0 && externalPort != 1 && externalPort != assignedExternalPort {
+			return 0, 0, fmt.Errorf("%s external port requested as %d but received %d",
+				protocolStr, externalPort, assignedExternalPort)
+		}
+	}
+
+	if protocolToExternalPort["tcp"] != protocolToExternalPort["udp"] {
+		return 0, 0, fmt.Errorf("TCP and UDP external ports differ: %d and %d",
+			protocolToExternalPort["tcp"], protocolToExternalPort["udp"])
+	}
+
+	return assignedInternalPort, assignedExternalPort, nil
+}
+
 func checkLifetime(logger utils.Logger, protocol string,
 	requested, actual time.Duration,
 ) {
@@ -81,27 +119,6 @@ func checkLifetime(logger utils.Logger, protocol string,
 	}
 }
 
-func checkInternalPort(logger utils.Logger, sent, received uint16) {
-	if sent != received {
-		logger.Warn(fmt.Sprintf("internal port assigned %d differs from requested internal port %d",
-			sent, received))
-	}
-}
-
-func checkInternalPorts(logger utils.Logger, udpPort, tcpPort uint16) {
-	if udpPort != tcpPort {
-		logger.Warn(fmt.Sprintf("UDP internal port %d differs from TCP internal port %d",
-			udpPort, tcpPort))
-	}
-}
-
-func checkExternalPorts(logger utils.Logger, udpPort, tcpPort uint16) {
-	if udpPort != tcpPort {
-		logger.Warn(fmt.Sprintf("UDP external port %d differs from TCP external port %d",
-			udpPort, tcpPort))
-	}
-}
-
 func (p *Provider) KeepPortForward(ctx context.Context,
 	objects utils.PortForwardObjects,
 ) (err error) {
@@ -117,22 +134,12 @@ func (p *Provider) KeepPortForward(ctx context.Context,
 		}
 
 		objects.Logger.Debug("refreshing forwarded ports since 45 seconds have elapsed")
-		networkProtocols := [...]string{"udp", "tcp"}
 		const lifetime = 60 * time.Second
 		for internalPort, externalPort := range p.internalToExternalPorts {
-			for _, networkProtocol := range networkProtocols {
-				_, assignedInternalPort, assignedExternalPort, assignedLiftetime, err := client.AddPortMapping(
-					ctx, objects.Gateway, networkProtocol, internalPort, externalPort, lifetime)
-				if err != nil {
-					return fmt.Errorf("adding port mapping: %w", err)
-				}
-				checkLifetime(logger, networkProtocol, lifetime, assignedLiftetime)
-				if externalPort != assignedExternalPort {
-					return fmt.Errorf("external port changed from %d to %d", externalPort, assignedExternalPort)
-				} else if internalPort != assignedInternalPort {
-					return fmt.Errorf("internal port changed from %d (for external port %d) to %d",
-						internalPort, externalPort, assignedInternalPort)
-				}
+			_, _, err := addPortMappingTCPUDP(ctx, client, logger, objects.Gateway, internalPort, externalPort, lifetime)
+			if err != nil {
+				return fmt.Errorf("refreshing port mapping for internal port %d and external port %d: %w",
+					internalPort, externalPort, err)
 			}
 			objects.Logger.Debug(fmt.Sprintf("port forwarded %d maintained", externalPort))
 		}

internal/provider/providers.go

@@ -20,7 +20,6 @@ import (
 	"github.com/qdm12/gluetun/internal/provider/ivpn"
 	"github.com/qdm12/gluetun/internal/provider/mullvad"
 	"github.com/qdm12/gluetun/internal/provider/nordvpn"
-	"github.com/qdm12/gluetun/internal/provider/ovpn"
 	"github.com/qdm12/gluetun/internal/provider/perfectprivacy"
 	"github.com/qdm12/gluetun/internal/provider/privado"
 	"github.com/qdm12/gluetun/internal/provider/privateinternetaccess"
@@ -68,7 +67,6 @@ func NewProviders(storage Storage, timeNow func() time.Time,
 		providers.Ivpn:                  ivpn.New(storage, client, updaterWarner, parallelResolver),
 		providers.Mullvad:               mullvad.New(storage, client),
 		providers.Nordvpn:               nordvpn.New(storage, client, updaterWarner),
-		providers.Ovpn:                  ovpn.New(storage, client),
 		providers.Perfectprivacy:        perfectprivacy.New(storage, unzipper, updaterWarner),
 		providers.Privado:               privado.New(storage, client, updaterWarner),
 		providers.PrivateInternetAccess: privateinternetaccess.New(storage, timeNow, client),

internal/provider/utils/connection.go

@@ -52,6 +52,8 @@ func GetConnection(provider string,
 	})
 
 	protocol := getProtocol(selection)
+	port := getPort(selection, defaults.OpenVPNTCPPort,
+		defaults.OpenVPNUDPPort, defaults.WireguardPort)
 
 	connections := make([]models.Connection, 0, len(servers))
 	for _, server := range servers {
@@ -67,9 +69,6 @@ func GetConnection(provider string,
 				hostname = server.OvpnX509
 			}
 
-			port := getPort(selection, server, defaults.OpenVPNTCPPort,
-				defaults.OpenVPNUDPPort, defaults.WireguardPort)
-
 			connection := models.Connection{
 				Type:        selection.VPN,
 				IP:          ip,

internal/provider/utils/port.go

@@ -6,44 +6,29 @@ import (
 	"github.com/qdm12/gluetun/internal/configuration/settings"
 	"github.com/qdm12/gluetun/internal/constants"
 	"github.com/qdm12/gluetun/internal/constants/vpn"
-	"github.com/qdm12/gluetun/internal/models"
 )
 
-func getPort(selection settings.ServerSelection, server models.Server,
+func getPort(selection settings.ServerSelection,
 	defaultOpenVPNTCP, defaultOpenVPNUDP, defaultWireguard uint16,
 ) (port uint16) {
 	switch selection.VPN {
 	case vpn.Wireguard:
 		customPort := *selection.Wireguard.EndpointPort
 		if customPort > 0 {
-			// Note: servers filtering ensures the custom port is within the
-			// server ports defined if any is set.
 			return customPort
 		}
-
-		if len(server.PortsUDP) > 0 {
-			defaultWireguard = server.PortsUDP[0]
-		}
 		checkDefined("Wireguard", defaultWireguard)
 		return defaultWireguard
 	default: // OpenVPN
 		customPort := *selection.OpenVPN.CustomPort
 		if customPort > 0 {
-			// Note: servers filtering ensures the custom port is within the
-			// server ports defined if any is set.
 			return customPort
 		}
 		if selection.OpenVPN.Protocol == constants.TCP {
-			if len(server.PortsTCP) > 0 {
-				defaultOpenVPNTCP = server.PortsTCP[0]
-			}
 			checkDefined("OpenVPN TCP", defaultOpenVPNTCP)
 			return defaultOpenVPNTCP
 		}
 
-		if len(server.PortsUDP) > 0 {
-			defaultOpenVPNUDP = server.PortsUDP[0]
-		}
 		checkDefined("OpenVPN UDP", defaultOpenVPNUDP)
 		return defaultOpenVPNUDP
 	}

internal/provider/utils/port_test.go

@@ -6,7 +6,6 @@ import (
 	"github.com/qdm12/gluetun/internal/configuration/settings"
 	"github.com/qdm12/gluetun/internal/constants"
 	"github.com/qdm12/gluetun/internal/constants/vpn"
-	"github.com/qdm12/gluetun/internal/models"
 	"github.com/stretchr/testify/assert"
 )
 
@@ -23,7 +22,6 @@ func Test_GetPort(t *testing.T) {
 
 	testCases := map[string]struct {
 		selection         settings.ServerSelection
-		server            models.Server
 		defaultOpenVPNTCP uint16
 		defaultOpenVPNUDP uint16
 		defaultWireguard  uint16
@@ -50,20 +48,6 @@ func Test_GetPort(t *testing.T) {
 			defaultWireguard:  defaultWireguard,
 			port:              defaultOpenVPNUDP,
 		},
-		"OpenVPN_server_port_udp": {
-			selection: settings.ServerSelection{
-				VPN: vpn.OpenVPN,
-				OpenVPN: settings.OpenVPNSelection{
-					CustomPort: uint16Ptr(0),
-					Protocol:   constants.UDP,
-				},
-			},
-			server: models.Server{
-				PortsUDP: []uint16{1234},
-			},
-			defaultOpenVPNUDP: defaultOpenVPNUDP,
-			port:              1234,
-		},
 		"OpenVPN UDP no default port defined": {
 			selection: settings.ServerSelection{
 				VPN: vpn.OpenVPN,
@@ -104,20 +88,6 @@ func Test_GetPort(t *testing.T) {
 			},
 			port: 1234,
 		},
-		"OpenVPN_server_port_tcp": {
-			selection: settings.ServerSelection{
-				VPN: vpn.OpenVPN,
-				OpenVPN: settings.OpenVPNSelection{
-					CustomPort: uint16Ptr(0),
-					Protocol:   constants.TCP,
-				},
-			},
-			server: models.Server{
-				PortsTCP: []uint16{1234},
-			},
-			defaultOpenVPNTCP: defaultOpenVPNTCP,
-			port:              1234,
-		},
 		"Wireguard": {
 			selection: settings.ServerSelection{
 				VPN: vpn.Wireguard,
@@ -135,19 +105,6 @@ func Test_GetPort(t *testing.T) {
 			defaultWireguard: defaultWireguard,
 			port:             1234,
 		},
-		"Wireguard_server_port": {
-			selection: settings.ServerSelection{
-				VPN: vpn.Wireguard,
-				Wireguard: settings.WireguardSelection{
-					EndpointPort: uint16Ptr(0),
-				},
-			},
-			server: models.Server{
-				PortsUDP: []uint16{1234},
-			},
-			defaultWireguard: defaultWireguard,
-			port:             1234,
-		},
 		"Wireguard no default port defined": {
 			selection: settings.ServerSelection{
 				VPN: vpn.Wireguard,
@@ -163,7 +120,6 @@ func Test_GetPort(t *testing.T) {
 			if testCase.panics != "" {
 				assert.PanicsWithValue(t, testCase.panics, func() {
 					_ = getPort(testCase.selection,
-						testCase.server,
 						testCase.defaultOpenVPNTCP,
 						testCase.defaultOpenVPNUDP,
 						testCase.defaultWireguard)
@@ -172,7 +128,6 @@ func Test_GetPort(t *testing.T) {
 			}
 
 			port := getPort(testCase.selection,
-				testCase.server,
 				testCase.defaultOpenVPNTCP,
 				testCase.defaultOpenVPNUDP,
 				testCase.defaultWireguard)

internal/restrictednet/client.go

@@ -0,0 +1,82 @@
+package restrictednet
+
+import (
+	"context"
+	"errors"
+	"fmt"
+	"net"
+	"net/http"
+	"net/netip"
+	"strconv"
+
+	"github.com/qdm12/dns/v2/pkg/provider"
+)
+
+// Client is a client for making restricted network requests,
+// such as opening temporary firewall rules for HTTPS connections.
+// It is not meant to be high performance, although it can be used for
+// multiple requests and concurrently.
+type Client struct {
+	outboundInterface string
+	ipv6Supported     bool
+	firewall          Firewall
+	dohServers        []provider.DoHServer
+}
+
+func New(settings Settings) *Client {
+	if err := settings.validate(); err != nil {
+		panic(fmt.Sprintf("invalid settings: %v", err)) // programming error
+	}
+	dohServers := make([]provider.DoHServer, len(settings.UpstreamResolvers))
+	for i, upstreamResolver := range settings.UpstreamResolvers {
+		dohServers[i] = upstreamResolver.DoH
+	}
+
+	return &Client{
+		outboundInterface: settings.DefaultInterface,
+		ipv6Supported:     *settings.IPv6Supported,
+		firewall:          settings.Firewall,
+		dohServers:        dohServers,
+	}
+}
+
+// OpenHTTPSByHostname opens an https connection through the firewall,
+// to the hostname which in the format `host:port`. The returned cleanup
+// function must be called to remove the temporary firewall rule and close connections.
+// It first resolves the domain in hostname using DNS over HTTPS and then opens
+// the restricted HTTPS connection to the resolved IP.
+func (c *Client) OpenHTTPSByHostname(ctx context.Context, hostname string) (
+	httpClient *http.Client, cleanup func() error, err error,
+) {
+	host, portStr, err := net.SplitHostPort(hostname)
+	if err != nil {
+		return nil, nil, fmt.Errorf("splitting host and port: %w", err)
+	}
+	resolvedIPs, err := c.ResolveName(ctx, host)
+	if err != nil {
+		return nil, nil, fmt.Errorf("resolving name: %w", err)
+	} else if len(resolvedIPs) == 0 {
+		return nil, nil, fmt.Errorf("no IP address found for name %q", host)
+	}
+
+	portUint, err := strconv.ParseUint(portStr, 10, 16)
+	if err != nil {
+		return nil, nil, fmt.Errorf("parsing port: %w", err)
+	} else if portUint == 0 {
+		return nil, nil, errors.New("destination port cannot be 0")
+	}
+	port := uint16(portUint)
+
+	errs := make([]error, 0, len(resolvedIPs))
+	for _, ip := range resolvedIPs {
+		addrPort := netip.AddrPortFrom(ip, port)
+		httpClient, cleanup, err := c.OpenHTTPS(ctx, host, addrPort)
+		if err != nil {
+			errs = append(errs, fmt.Errorf("for %s: %w", ip, err))
+			continue
+		}
+		return httpClient, cleanup, nil
+	}
+
+	return nil, nil, fmt.Errorf("opening HTTPS to %s: %w", hostname, errors.Join(errs...))
+}

internal/restrictednet/helpers_test.go

@@ -0,0 +1,7 @@
+//go:build integration
+
+package restrictednet
+
+func ptrTo[T any](value T) *T {
+	return &value
+}

internal/restrictednet/https.go

@@ -0,0 +1,202 @@
+package restrictednet
+
+import (
+	"context"
+	"crypto/tls"
+	"errors"
+	"fmt"
+	"net"
+	"net/http"
+	"net/netip"
+	"os"
+	"time"
+
+	"github.com/jsimonetti/rtnetlink"
+	"github.com/qdm12/gluetun/internal/pmtud/constants"
+)
+
+// OpenHTTPS opens temporary restrictive firewall output for one HTTPS destination.
+// The returned [*http.Client] must be used sequentially only, and each request must
+// have its response body fully read/discarded and then closed.
+// The returned cleanup function must be called to remove the temporary firewall rule and close connections.
+func (c *Client) OpenHTTPS(ctx context.Context, destinationTLSName string, destinationAddrPort netip.AddrPort,
+) (httpClient *http.Client, cleanup func() error, err error) {
+	fd, sourceAddrPort, err := bindSourceConnection(destinationAddrPort.Addr())
+	if err != nil {
+		return nil, nil, fmt.Errorf("binding source port: %w", err)
+	}
+
+	const remove = false
+	err = c.firewall.AcceptOutputFromIPPortToIPPort(ctx, "tcp", c.outboundInterface,
+		sourceAddrPort, destinationAddrPort, remove)
+	if err != nil {
+		closeFD(fd)
+		return nil, nil, fmt.Errorf("allowing output traffic through firewall: %w", err)
+	}
+
+	connection, err := connectSourceConnection(ctx, fd, destinationAddrPort)
+	if err != nil {
+		const remove = true
+		_ = c.firewall.AcceptOutputFromIPPortToIPPort(context.Background(), "tcp", c.outboundInterface,
+			sourceAddrPort, destinationAddrPort, remove)
+		return nil, nil, fmt.Errorf("connecting source socket: %w", err)
+	}
+
+	dial := makeDial(connection, destinationTLSName)
+	httpClient = newHTTPSClient(destinationTLSName, dial)
+	cleanup = func() error {
+		var errs []error
+		httpClient.CloseIdleConnections()
+		err := connection.Close()
+		if err != nil && !errors.Is(err, net.ErrClosed) {
+			errs = append(errs, fmt.Errorf("closing connection: %w", err))
+		}
+		const remove = true
+		err = c.firewall.AcceptOutputFromIPPortToIPPort(context.Background(), "tcp", c.outboundInterface,
+			sourceAddrPort, destinationAddrPort, remove)
+		if err != nil {
+			errs = append(errs, fmt.Errorf("removing output traffic rule: %w", err))
+		}
+		if len(errs) > 0 {
+			return errors.Join(errs...)
+		}
+		return nil
+	}
+	return httpClient, cleanup, nil
+}
+
+type dialFunc func(ctx context.Context, network, address string) (net.Conn, error)
+
+func newHTTPSClient(destinationTLSName string, dial dialFunc) *http.Client {
+	const timeout = 5 * time.Second
+	transport := &http.Transport{
+		MaxIdleConns:        1,
+		MaxIdleConnsPerHost: 1,
+		MaxConnsPerHost:     1,
+		TLSClientConfig: &tls.Config{
+			MinVersion: tls.VersionTLS12,
+			ServerName: destinationTLSName,
+		},
+		DialContext: dial,
+	}
+	return &http.Client{
+		Timeout:   timeout,
+		Transport: transport,
+	}
+}
+
+func makeDial(connection net.Conn, tlsName string) dialFunc {
+	_, destinationPort, err := net.SplitHostPort(connection.RemoteAddr().String())
+	if err != nil {
+		panic(err) // connection remote address should always be in the form "host:port"
+	}
+	expectedAddress := net.JoinHostPort(tlsName, destinationPort)
+	used := false
+	return func(_ context.Context, network, address string) (net.Conn, error) {
+		if used {
+			return nil, errors.New("dial function called more than once")
+		}
+		used = true
+		switch network {
+		case "tcp", "tcp4", "tcp6":
+		default:
+			return nil, fmt.Errorf("unexpected dial network %q", network)
+		}
+		if address != expectedAddress {
+			return nil, fmt.Errorf("unexpected dial address %q (expected %q)", address, expectedAddress)
+		}
+		return connection, nil
+	}
+}
+
+func bindSourceConnection(destinationIP netip.Addr) (fd int, sourceAddr netip.AddrPort, err error) {
+	sourceIP, err := sourceIPForDestination(destinationIP)
+	if err != nil {
+		return 0, netip.AddrPort{}, fmt.Errorf("finding source IP: %w", err)
+	}
+
+	family := constants.AF_INET
+	if sourceIP.Is6() {
+		family = constants.AF_INET6
+	}
+
+	fd, err = newTCPSockStream(family)
+	if err != nil {
+		return 0, netip.AddrPort{}, fmt.Errorf("creating socket: %w", err)
+	}
+
+	bindAddrPort := netip.AddrPortFrom(sourceIP, 0)
+	err = bindFD(fd, bindAddrPort)
+	if err != nil {
+		closeFD(fd)
+		return 0, netip.AddrPort{}, fmt.Errorf("binding socket: %w", err)
+	}
+
+	sourceAddr, err = fdToSourceAddr(fd)
+	if err != nil {
+		closeFD(fd)
+		return 0, netip.AddrPort{}, fmt.Errorf("getting source address: %w", err)
+	}
+
+	return fd, sourceAddr, nil
+}
+
+func connectSourceConnection(ctx context.Context, fd int, destinationAddrPort netip.AddrPort) (
+	connection net.Conn, err error,
+) {
+	err = connectFD(ctx, fd, destinationAddrPort)
+	if err != nil {
+		closeFD(fd)
+		return nil, fmt.Errorf("connecting socket: %w", err)
+	}
+
+	file := os.NewFile(uintptr(fd), "")
+	if file == nil {
+		closeFD(fd)
+		return nil, fmt.Errorf("creating socket file")
+	}
+	defer file.Close()
+
+	connection, err = net.FileConn(file)
+	if err != nil {
+		return nil, fmt.Errorf("wrapping socket connection: %w", err)
+	}
+
+	return connection, nil
+}
+
+func sourceIPForDestination(destinationIP netip.Addr) (srcIP netip.Addr, err error) {
+	conn, err := rtnetlink.Dial(nil)
+	if err != nil {
+		return netip.Addr{}, err
+	}
+	defer conn.Close()
+
+	family := uint8(constants.AF_INET)
+	if destinationIP.Is6() {
+		family = constants.AF_INET6
+	}
+
+	requestMessage := &rtnetlink.RouteMessage{
+		Family: family,
+		Attributes: rtnetlink.RouteAttributes{
+			Dst: destinationIP.AsSlice(),
+		},
+	}
+	messages, err := conn.Route.Get(requestMessage)
+	if err != nil {
+		return netip.Addr{}, fmt.Errorf("getting routes to %s: %w", destinationIP, err)
+	}
+
+	for _, message := range messages {
+		if message.Attributes.Src == nil {
+			continue
+		}
+		if message.Attributes.Src.To4() == nil {
+			return netip.AddrFrom16([16]byte(message.Attributes.Src)), nil
+		}
+		return netip.AddrFrom4([4]byte(message.Attributes.Src)), nil
+	}
+
+	return netip.Addr{}, fmt.Errorf("no route to %s", destinationIP)
+}

internal/restrictednet/https_integration_test.go

@@ -0,0 +1,117 @@
+//go:build integration
+
+package restrictednet
+
+import (
+	"context"
+	"fmt"
+	"io"
+	"net/http"
+	"net/netip"
+	"testing"
+
+	"github.com/golang/mock/gomock"
+	"github.com/qdm12/dns/v2/pkg/provider"
+	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
+)
+
+type listenAddrPortMatcher struct {
+	expected netip.AddrPort
+}
+
+func (m listenAddrPortMatcher) Matches(x any) bool {
+	ip, ok := x.(netip.AddrPort)
+	if !ok {
+		return false
+	}
+	if m.expected.IsValid() {
+		return ip == m.expected
+	}
+	return ip.IsValid() && ip.Addr().IsValid() && ip.Port() > 0
+}
+
+func (m listenAddrPortMatcher) String() string {
+	if m.expected.IsValid() {
+		return "is the same as " + m.expected.String()
+	}
+	return "is a valid netip.AddrPort with a valid IP and non-zero port"
+}
+
+type destinationAddrPortMatcher struct {
+	expected netip.AddrPort
+}
+
+func (m destinationAddrPortMatcher) Matches(x any) bool {
+	ip, ok := x.(netip.AddrPort)
+	if !ok {
+		return false
+	}
+	if m.expected.IsValid() {
+		return ip == m.expected
+	}
+	return ip.IsValid() && ip.Port() == m.expected.Port()
+}
+
+func (m destinationAddrPortMatcher) String() string {
+	if m.expected.IsValid() {
+		return "is the same as " + m.expected.String()
+	}
+	return "matches the port " + fmt.Sprint(m.expected.Port())
+}
+
+func Test_Client_OpenHTTPS(t *testing.T) {
+	t.Parallel()
+	ctx := t.Context()
+	ctrl := gomock.NewController(t)
+
+	const destinationTLSName = "one.one.one.one"
+	destinationAddrPort := netip.AddrPortFrom(netip.AddrFrom4([4]byte{1, 1, 1, 1}), 443)
+
+	firewall := NewMockFirewall(ctrl)
+	sourceMatcher := listenAddrPortMatcher{}
+	firewall.EXPECT().AcceptOutputFromIPPortToIPPort(
+		ctx, "tcp", "eth0", sourceMatcher, destinationAddrPort, false,
+	).DoAndReturn(func(_ context.Context,
+		_, _ string, source, _ netip.AddrPort, _ bool,
+	) error {
+		sourceMatcher.expected = source
+		return nil
+	})
+	firewall.EXPECT().AcceptOutputFromIPPortToIPPort(
+		context.Background(), "tcp", "eth0", sourceMatcher, destinationAddrPort, true,
+	).Return(nil)
+
+	const ipv6Supported = false
+	upstreamResolvers := []provider.Provider{provider.Google()}
+	settings := Settings{
+		Firewall:          firewall,
+		DefaultInterface:  "eth0",
+		IPv6Supported:     ptrTo(ipv6Supported),
+		UpstreamResolvers: upstreamResolvers,
+	}
+	client := New(settings)
+
+	httpClient, cleanup, err := client.OpenHTTPS(ctx, destinationTLSName, destinationAddrPort)
+	require.NoError(t, err)
+	require.NotNil(t, httpClient)
+	require.NotNil(t, cleanup)
+
+	const requests = 2
+
+	for range requests {
+		request, err := http.NewRequestWithContext(ctx, http.MethodGet, "https://"+destinationTLSName, nil)
+		require.NoError(t, err)
+
+		response, err := httpClient.Do(request)
+		require.NoError(t, err)
+		_, err = io.Copy(io.Discard, response.Body)
+		require.NoError(t, err)
+		err = response.Body.Close()
+		require.NoError(t, err)
+		assert.Equal(t, http.StatusOK, response.StatusCode)
+	}
+
+	err = cleanup()
+	require.NoError(t, err)
+}

internal/restrictednet/interfaces.go

@@ -0,0 +1,12 @@
+package restrictednet
+
+import (
+	"context"
+	"net/netip"
+)
+
+type Firewall interface {
+	AcceptOutputFromIPPortToIPPort(ctx context.Context,
+		protocol, intf string, source, destination netip.AddrPort, remove bool,
+	) error
+}

internal/restrictednet/mocks_generate_test.go

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

internal/restrictednet/mocks_test.go

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

internal/restrictednet/resolve.go

@@ -0,0 +1,205 @@
+package restrictednet
+
+import (
+	"bytes"
+	"context"
+	"errors"
+	"fmt"
+	"io"
+	"net/http"
+	"net/netip"
+	"net/url"
+	"strconv"
+
+	"github.com/miekg/dns"
+)
+
+// ResolveName resolves the given host name to IP addresses using DoH servers,
+// while opening temporary restrictive firewall rules for HTTPS traffic to DoH servers.
+// The host must be a single well-formed domain name, without port or path.
+func (c *Client) ResolveName(ctx context.Context, host string) (
+	resolvedAddresses []netip.Addr, err error,
+) {
+	const maxTypes = 2
+	questionTypes := make([]uint16, 0, maxTypes)
+	if c.ipv6Supported {
+		questionTypes = append(questionTypes, dns.TypeAAAA)
+	}
+	questionTypes = append(questionTypes, dns.TypeA)
+
+	var addresses []netip.Addr
+	errs := make([]error, 0, len(questionTypes))
+	for _, questionType := range questionTypes {
+		answerAddresses, err := c.resolveOneQuestionType(ctx, host, questionType)
+		if err != nil {
+			errs = append(errs, err)
+			continue
+		}
+		addresses = append(addresses, answerAddresses...)
+	}
+
+	switch {
+	case len(addresses) > 0:
+		return addresses, nil
+	case len(errs) == 0:
+		return nil, nil // no address found
+	default: // errors
+		return nil, fmt.Errorf("resolving host %q: %w", host, errors.Join(errs...))
+	}
+}
+
+func (c *Client) resolveOneQuestionType(ctx context.Context,
+	host string, questionType uint16,
+) (addresses []netip.Addr, err error) {
+	queryMessage := &dns.Msg{}
+	queryMessage.SetQuestion(dns.Fqdn(host), questionType)
+	queryWire, err := queryMessage.Pack()
+	if err != nil {
+		return nil, fmt.Errorf("packing DNS query: %w", err)
+	}
+
+	// Try every DoH server and every of each of their IP until we get a non-empty
+	// successful response.
+	errs := make([]error, 0)
+	for _, dohServer := range c.dohServers {
+		dohURL, err := url.Parse(dohServer.URL)
+		if err != nil {
+			errs = append(errs,
+				fmt.Errorf("parsing DoH server URL %s: %w", dohServer.URL, err))
+			continue
+		}
+
+		dohServerIPs := make([]netip.Addr, 0, len(dohServer.IPv4)+len(dohServer.IPv6))
+		if c.ipv6Supported {
+			// Prefer IPv6 addresses if IPv6 is supported
+			dohServerIPs = append(dohServerIPs, dohServer.IPv6...)
+		}
+		dohServerIPs = append(dohServerIPs, dohServer.IPv4...)
+
+		for _, dohServerIP := range dohServerIPs {
+			const defaultDoHPort uint16 = 443
+			port := defaultDoHPort
+			if portStr := dohURL.Port(); portStr != "" {
+				port, err = parseDestinationPort(portStr)
+				if err != nil {
+					errs = append(errs, fmt.Errorf("parsing DoH server port: %w", err))
+					continue
+				}
+			}
+			dohServerAddrPort := netip.AddrPortFrom(dohServerIP, port)
+			responseMessage, err := c.doHQuery(ctx, queryWire, dohURL, dohServerAddrPort)
+			switch {
+			case err != nil:
+				errs = append(errs, fmt.Errorf("querying DoH server %q (%s): %w",
+					dohServer.URL, dohServerAddrPort, err))
+				continue
+			case responseMessage.Rcode != dns.RcodeSuccess:
+				errs = append(errs, fmt.Errorf("querying DoH server %q (%s): DNS rcode %s",
+					dohServer.URL, dohServerAddrPort, dns.RcodeToString[responseMessage.Rcode]))
+				continue
+			}
+			addresses := answersToNetipAddrs(responseMessage)
+			if len(addresses) == 0 {
+				continue
+			}
+			return addresses, nil
+		}
+	}
+
+	if len(errs) == 0 {
+		return nil, nil
+	}
+
+	return nil, fmt.Errorf("resolving %s %s: %w",
+		dns.TypeToString[questionType], host, errors.Join(errs...))
+}
+
+func (c *Client) doHQuery(ctx context.Context, queryWire []byte,
+	dohURL *url.URL, dohServerAddrPort netip.AddrPort,
+) (responseMessage *dns.Msg, err error) {
+	httpClient, cleanup, err := c.OpenHTTPS(ctx, dohURL.Hostname(), dohServerAddrPort)
+	if err != nil {
+		return nil, fmt.Errorf("opening https connection: %w", err)
+	}
+	defer func() {
+		closeErr := cleanup()
+		if err == nil && closeErr != nil {
+			err = fmt.Errorf("cleaning up https connection: %w", closeErr)
+		}
+	}()
+
+	requestBody := bytes.NewReader(queryWire)
+	request, err := http.NewRequestWithContext(ctx, http.MethodPost, dohURL.String(), requestBody)
+	if err != nil {
+		return nil, fmt.Errorf("creating request: %w", err)
+	}
+	request.Header.Set("Content-Type", "application/dns-message")
+	request.Header.Set("Accept", "application/dns-message")
+
+	response, err := httpClient.Do(request)
+	if err != nil {
+		return nil, err
+	}
+
+	responseData, err := io.ReadAll(response.Body)
+	if err != nil {
+		_ = response.Body.Close()
+		return nil, fmt.Errorf("reading response body: %w", err)
+	}
+
+	err = response.Body.Close()
+	if err != nil {
+		return nil, fmt.Errorf("closing response body: %w", err)
+	}
+
+	if response.StatusCode != http.StatusOK {
+		return nil, fmt.Errorf("response status code is %s (data length %d)",
+			response.Status, len(responseData))
+	}
+
+	responseMessage = new(dns.Msg)
+	err = responseMessage.Unpack(responseData)
+	if err != nil {
+		return nil, fmt.Errorf("parsing DoH response: %w", err)
+	}
+
+	return responseMessage, nil
+}
+
+func answersToNetipAddrs(message *dns.Msg) (addresses []netip.Addr) {
+	if message == nil {
+		return nil
+	}
+	addresses = make([]netip.Addr, 0, len(message.Answer))
+	for _, answer := range message.Answer {
+		switch record := answer.(type) {
+		case *dns.A:
+			address, ok := netip.AddrFromSlice(record.A)
+			if ok {
+				addresses = append(addresses, address.Unmap())
+			}
+		case *dns.AAAA:
+			address, ok := netip.AddrFromSlice(record.AAAA)
+			if ok {
+				addresses = append(addresses, address)
+			}
+		}
+	}
+	return addresses
+}
+
+func parseDestinationPort(portStr string) (port uint16, err error) {
+	portUint, err := strconv.ParseUint(portStr, 10, 16)
+	if err != nil {
+		return 0, err
+	}
+
+	const maxPortUint = 65535
+	switch {
+	case portUint == 0:
+		return 0, errors.New("port cannot be 0")
+	case portUint > maxPortUint:
+		return 0, fmt.Errorf("port cannot be greater than %d", maxPortUint)
+	}
+	return uint16(portUint), nil
+}

internal/restrictednet/resolve_integration_test.go

@@ -0,0 +1,110 @@
+//go:build integration
+
+package restrictednet
+
+import (
+	"context"
+	"net"
+	"net/netip"
+	"testing"
+
+	"github.com/golang/mock/gomock"
+	"github.com/miekg/dns"
+	"github.com/qdm12/dns/v2/pkg/provider"
+	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
+)
+
+func Test_Client_ResolveName(t *testing.T) {
+	t.Parallel()
+	ctx := t.Context()
+	ctrl := gomock.NewController(t)
+
+	firewall := NewMockFirewall(ctrl)
+	sourceMatcher := listenAddrPortMatcher{}
+	destinationMatcher := destinationAddrPortMatcher{
+		expected: netip.AddrPortFrom(netip.Addr{}, 443),
+	}
+
+	// Add rule
+	firstCall := firewall.EXPECT().AcceptOutputFromIPPortToIPPort(
+		ctx, "tcp", "eth0", sourceMatcher, destinationMatcher, false,
+	).DoAndReturn(func(
+		_ context.Context, _, _ string, source, destination netip.AddrPort, _ bool,
+	) error {
+		sourceMatcher.expected = source
+		destinationMatcher.expected = destination
+		return nil
+	})
+
+	// Removal rule
+	firewall.EXPECT().AcceptOutputFromIPPortToIPPort(
+		context.Background(), "tcp", "eth0", sourceMatcher, destinationMatcher, true,
+	).Return(nil).After(firstCall)
+
+	settings := Settings{
+		DefaultInterface:  "eth0",
+		IPv6Supported:     ptrTo(false),
+		Firewall:          firewall,
+		UpstreamResolvers: []provider.Provider{provider.Cloudflare()},
+	}
+	client := New(settings)
+
+	addresses, err := client.ResolveName(ctx, "github.com")
+	require.NoError(t, err)
+	assert.NotEmpty(t, addresses)
+}
+
+func Test_answersToNetipAddrs(t *testing.T) {
+	t.Parallel()
+
+	testCases := map[string]struct {
+		message  *dns.Msg
+		expected []netip.Addr
+	}{
+		"nil_message": {},
+		"no_answers": {
+			message:  &dns.Msg{},
+			expected: []netip.Addr{},
+		},
+		"a_record": {
+			message: &dns.Msg{Answer: []dns.RR{
+				&dns.A{
+					Hdr: dns.RR_Header{Name: "example.com.", Rrtype: dns.TypeA, Class: dns.ClassINET},
+					A:   net.IP{1, 1, 1, 1},
+				},
+			}},
+			expected: []netip.Addr{netip.MustParseAddr("1.1.1.1")},
+		},
+		"aaaa_record": {
+			message: &dns.Msg{Answer: []dns.RR{
+				&dns.AAAA{
+					Hdr:  dns.RR_Header{Name: "example.com.", Rrtype: dns.TypeAAAA, Class: dns.ClassINET},
+					AAAA: net.IP{0x20, 0x01, 0x48, 0x60, 0x48, 0x60, 0, 0, 0, 0, 0, 0, 0, 0, 0x88, 0x88},
+				},
+			}},
+			expected: []netip.Addr{netip.MustParseAddr("2001:4860:4860::8888")},
+		},
+		"mixed_records": {
+			message: &dns.Msg{Answer: []dns.RR{
+				&dns.A{
+					Hdr: dns.RR_Header{Name: "example.com.", Rrtype: dns.TypeA, Class: dns.ClassINET},
+					A:   net.IP{1, 1, 1, 1},
+				},
+				&dns.AAAA{
+					Hdr:  dns.RR_Header{Name: "example.com.", Rrtype: dns.TypeAAAA, Class: dns.ClassINET},
+					AAAA: net.IP{0x20, 0x01, 0x48, 0x60, 0x48, 0x60, 0, 0, 0, 0, 0, 0, 0, 0, 0x88, 0x88},
+				},
+			}},
+			expected: []netip.Addr{netip.MustParseAddr("1.1.1.1"), netip.MustParseAddr("2001:4860:4860::8888")},
+		},
+	}
+
+	for testName, testCase := range testCases {
+		t.Run(testName, func(t *testing.T) {
+			t.Parallel()
+			addresses := answersToNetipAddrs(testCase.message)
+			assert.Equal(t, testCase.expected, addresses)
+		})
+	}
+}

internal/restrictednet/settings.go

@@ -0,0 +1,28 @@
+package restrictednet
+
+import (
+	"errors"
+
+	"github.com/qdm12/dns/v2/pkg/provider"
+)
+
+type Settings struct {
+	DefaultInterface  string
+	IPv6Supported     *bool
+	Firewall          Firewall
+	UpstreamResolvers []provider.Provider
+}
+
+func (s *Settings) validate() error {
+	switch {
+	case s.DefaultInterface == "":
+		return errors.New("default interface is not set")
+	case s.IPv6Supported == nil:
+		return errors.New("IPv6 support field is not set")
+	case s.Firewall == nil:
+		return errors.New("firewall is not set")
+	case len(s.UpstreamResolvers) == 0:
+		return errors.New("no upstream resolvers provided")
+	}
+	return nil
+}

internal/restrictednet/unix.go

@@ -0,0 +1,121 @@
+//go:build !windows
+
+package restrictednet
+
+import (
+	"context"
+	"errors"
+	"fmt"
+	"net/netip"
+	"time"
+
+	"golang.org/x/sys/unix"
+)
+
+func closeFD(fd int) {
+	unix.Close(fd)
+}
+
+func newTCPSockStream(family int) (fd int, err error) {
+	fd, err = unix.Socket(family, unix.SOCK_STREAM, unix.IPPROTO_TCP)
+	if err != nil {
+		return 0, err
+	}
+	err = unix.SetNonblock(fd, true)
+	if err != nil {
+		_ = unix.Close(fd)
+		return 0, err
+	}
+	return fd, nil
+}
+
+func bindFD(fd int, address netip.AddrPort) error {
+	bindAddr := makeSockAddr(address)
+	return unix.Bind(fd, bindAddr)
+}
+
+func connectFD(ctx context.Context, fd int, destination netip.AddrPort) error {
+	err := unix.Connect(fd, makeSockAddr(destination))
+	switch {
+	case err == nil:
+		return nil
+	case !errors.Is(err, unix.EINPROGRESS):
+		return err
+	}
+
+	for {
+		select {
+		case <-ctx.Done():
+			return ctx.Err()
+		default:
+			bitsIndex := fd / 64 //nolint:mnd
+			if bitsIndex >= len(unix.FdSet{}.Bits) {
+				return fmt.Errorf("fd %d exceeds unix.Select FdSet capacity", fd)
+			}
+			wset := &unix.FdSet{}
+			wset.Bits[bitsIndex] |= 1 << (uint64(fd) % 64) //nolint:gosec,mnd
+			eset := &unix.FdSet{}
+			eset.Bits[bitsIndex] |= 1 << (uint64(fd) % 64) //nolint:gosec,mnd
+			const selectTimeout = 50 * time.Millisecond
+			timeval := unix.NsecToTimeval(int64(selectTimeout))
+
+			// Wait for the FD to become writable or hit an error state
+			n, err := unix.Select(fd+1, nil, wset, eset, &timeval)
+			if err != nil {
+				if errors.Is(err, unix.EINTR) {
+					continue // Syscall interrupted, try again
+				}
+				return fmt.Errorf("select error: %w", err)
+			} else if n == 0 {
+				continue // no status change yet
+			}
+
+			// Check if the socket encountered an error
+			n, err = unix.GetsockoptInt(fd, unix.SOL_SOCKET, unix.SO_ERROR)
+			if err != nil {
+				return fmt.Errorf("getsockopt error: %w", err)
+			} else if n != 0 {
+				return fmt.Errorf("connect failed asynchronously: %w", unix.Errno(n))
+			}
+
+			return nil
+		}
+	}
+}
+
+func fdToSourceAddr(fd int) (sourceAddrPort netip.AddrPort, err error) {
+	sockAddr, err := unix.Getsockname(fd)
+	if err != nil {
+		return netip.AddrPort{}, fmt.Errorf("getting sockname: %w", err)
+	}
+
+	sourceAddrPort, err = sockAddrToAddrPort(sockAddr)
+	if err != nil {
+		return netip.AddrPort{}, err
+	}
+	return sourceAddrPort, nil
+}
+
+func makeSockAddr(addressPort netip.AddrPort) unix.Sockaddr {
+	if addressPort.Addr().Is4() {
+		return &unix.SockaddrInet4{
+			Port: int(addressPort.Port()),
+			Addr: addressPort.Addr().As4(),
+		}
+	}
+	return &unix.SockaddrInet6{
+		Port: int(addressPort.Port()),
+		Addr: addressPort.Addr().As16(),
+	}
+}
+
+func sockAddrToAddrPort(sockAddr unix.Sockaddr) (addrPort netip.AddrPort, err error) {
+	switch typedSockAddr := sockAddr.(type) {
+	case *unix.SockaddrInet4:
+		return netip.AddrPortFrom(netip.AddrFrom4(typedSockAddr.Addr), uint16(typedSockAddr.Port)), nil //nolint:gosec
+	case *unix.SockaddrInet6:
+		return netip.AddrPortFrom(netip.AddrFrom16(typedSockAddr.Addr), uint16(typedSockAddr.Port)), nil //nolint:gosec
+	default:
+		return netip.AddrPort{}, fmt.Errorf("unexpected socket address type %T", typedSockAddr)
+	}
+}

internal/restrictednet/windows.go

@@ -0,0 +1,28 @@
+//go:build windows
+
+package restrictednet
+
+import (
+	"context"
+	"net/netip"
+)
+
+func closeFD(fd int) {
+	panic("not implemented")
+}
+
+func newTCPSockStream(family int) (fd int, err error) {
+	panic("not implemented")
+}
+
+func bindFD(fd int, address netip.AddrPort) error {
+	panic("not implemented")
+}
+
+func connectFD(ctx context.Context, fd int, destination netip.AddrPort) error {
+	panic("not implemented")
+}
+
+func fdToSourceAddr(fd int) (sourceAddrPort netip.AddrPort, err error) {
+	panic("not implemented")
+}

internal/socks5/constants.go

@@ -43,7 +43,6 @@ type cmdType byte
 
 const (
 	connect      cmdType = 1
-	bind         cmdType = 2
 	udpAssociate cmdType = 3
 )
 
@@ -51,8 +50,6 @@ func (c cmdType) String() string {
 	switch c {
 	case connect:
 		return "connect"
-	case bind:
-		return "bind"
 	case udpAssociate:
 		return "UDP associate"
 	default:

internal/socks5/response.go

@@ -10,7 +10,7 @@ import (
 )
 
 // See https://datatracker.ietf.org/doc/html/rfc1928#section-6
-func (c *socksConn) encodeFailedResponse(writer io.Writer, socksVersion byte, reply replyCode) { //nolint:unparam
+func (c *socksConn) encodeFailedResponse(writer io.Writer, socksVersion byte, reply replyCode) {
 	_, err := writer.Write([]byte{
 		socksVersion,
 		byte(reply),

internal/socks5/server.go

@@ -2,6 +2,7 @@ package socks5
 
 import (
 	"context"
+	"errors"
 	"fmt"
 	"net"
 	"sync"
@@ -15,12 +16,13 @@ type server struct {
 	logger   Logger
 
 	// internal fields
-	listener        net.Listener
+	tcpListener     net.Listener
+	udpRouter       *udpRouter
 	listening       atomic.Bool
 	socksConnCtx    context.Context //nolint:containedctx
 	socksConnCancel context.CancelFunc
-	done            <-chan struct{}
-	stopping        atomic.Bool
+	done            <-chan error
+	stopCh          chan<- struct{}
 }
 
 func newServer(settings Settings) *server {
@@ -39,19 +41,28 @@ func (s *server) String() string {
 func (s *server) Start(ctx context.Context) (runErr <-chan error, err error) {
 	s.socksConnCtx, s.socksConnCancel = context.WithCancel(context.Background())
 	config := &net.ListenConfig{}
-	s.listener, err = config.Listen(ctx, "tcp", s.address)
+	s.tcpListener, err = config.Listen(ctx, "tcp", s.address)
 	if err != nil {
-		return nil, fmt.Errorf("listening on %s: %w", s.address, err)
+		return nil, fmt.Errorf("TCP listening on %s: %w", s.address, err)
+	}
+
+	s.udpRouter, err = newUDPRouter(ctx, s.address, s.logger)
+	if err != nil {
+		_ = s.tcpListener.Close()
+		return nil, fmt.Errorf("creating UDP router: %w", err)
 	}
 	s.listening.Store(true)
-	s.logger.Infof("SOCKS5 server listening on %s", s.listener.Addr())
+	s.logger.Infof("SOCKS5 TCP server listening on %s", s.tcpListener.Addr())
+	s.logger.Infof("SOCKS5 UDP server listening on %s", s.udpRouter.localAddress())
 
 	ready := make(chan struct{})
 	runErrCh := make(chan error)
 	runErr = runErrCh
-	done := make(chan struct{})
+	done := make(chan error)
 	s.done = done
-	go s.runServer(ready, runErrCh, done)
+	stop := make(chan struct{})
+	s.stopCh = stop
+	go s.runServer(ready, runErrCh, stop, done)
 	select {
 	case <-ready:
 	case <-ctx.Done():
@@ -62,61 +73,90 @@ func (s *server) Start(ctx context.Context) (runErr <-chan error, err error) {
 }
 
 func (s *server) runServer(ready chan<- struct{},
-	runErrCh chan<- error, done chan<- struct{},
+	runErrCh chan<- error, stop <-chan struct{}, done chan<- error,
 ) {
 	close(ready)
 	defer close(done)
-	wg := new(sync.WaitGroup)
-	defer wg.Wait()
 
-	dialer := &net.Dialer{}
-	for {
-		connection, err := s.listener.Accept()
-		if err != nil {
-			if !s.stopping.Load() {
-				_ = s.stop()
-				runErrCh <- fmt.Errorf("accepting connection: %w", err)
-			}
-			return
-		}
-		wg.Add(1)
-		go func(ctx context.Context, connection net.Conn,
-			dialer *net.Dialer, wg *sync.WaitGroup,
-		) {
-			defer wg.Done()
-			socksConn := &socksConn{
-				dialer:     dialer,
-				username:   s.username,
-				password:   s.password,
-				clientConn: connection,
-				logger:     s.logger,
-			}
-			err := socksConn.run(ctx)
+	udpErrCh := make(chan error)
+	go func() {
+		udpErrCh <- s.udpRouter.run(s.socksConnCtx)
+	}()
+
+	tcpErrCh := make(chan error)
+	go func() {
+		var wg sync.WaitGroup
+		defer wg.Wait()
+
+		dialer := &net.Dialer{}
+		for {
+			connection, err := s.tcpListener.Accept()
 			if err != nil {
-				s.logger.Infof("running socks connection: %s", err)
+				s.socksConnCancel() // stop ongoing TCP socks connections - no impact on UDP
+				tcpErrCh <- fmt.Errorf("accepting connection: %w", err)
+				return
 			}
-		}(s.socksConnCtx, connection, dialer, wg)
+			wg.Go(func() {
+				connection := connection // capture loop variable
+				socksConn := &socksConn{
+					dialer:     dialer,
+					username:   s.username,
+					password:   s.password,
+					clientConn: connection,
+					udpRouter:  s.udpRouter,
+					logger:     s.logger,
+				}
+				err := socksConn.run(s.socksConnCtx)
+				if err != nil {
+					s.logger.Infof("running socks connection: %s", err)
+				}
+			})
+		}
+	}()
+
+	select {
+	case <-stop:
+		s.listening.Store(false)
+		var errs []error
+		err := s.tcpListener.Close()
+		if err != nil {
+			errs = append(errs, fmt.Errorf("closing TCP listener: %w", err))
+		}
+		// stop ongoing TCP socks connections. This impacts the udpRouter run error when it is being closed.
+		s.socksConnCancel()
+		<-tcpErrCh // wait for TCP server to stop
+		err = s.udpRouter.close()
+		if err != nil {
+			errs = append(errs, fmt.Errorf("closing UDP router: %w", err))
+		}
+		<-udpErrCh // wait for UDP router to stop
+		if len(errs) > 0 {
+			// Only write to the done channel if the [server.Stop] method is waiting to read from it
+			done <- errors.Join(errs...)
+		}
+		// If no error, the done channel is closed so the error is effectively `nil`
+		// Note: do NOT write an error the runError channel, since we are stopping the server gracefully.
+	case err := <-udpErrCh:
+		_ = s.tcpListener.Close() // stop accepting new TCP connections
+		s.socksConnCancel()       // stop ongoing TCP socks connections
+		<-tcpErrCh                // wait for TCP server to stop
+		runErrCh <- fmt.Errorf("running UDP router: %w", err)
+	case err := <-tcpErrCh:
+		s.socksConnCancel()
+		_ = s.udpRouter.close() // stop UDP router
+		<-udpErrCh              // wait for UDP router to stop
+		runErrCh <- fmt.Errorf("running TCP server: %w", err)
 	}
 }
 
 func (s *server) Stop() (err error) {
-	s.stopping.Store(true)
-	err = s.stop()
-	<-s.done // wait for run goroutine to finish
-	s.stopping.Store(false)
-	return err
-}
-
-func (s *server) stop() error {
-	s.listening.Store(false)
-	err := s.listener.Close()
-	s.socksConnCancel() // stop ongoing socks connections
-	return err
+	close(s.stopCh)
+	return <-s.done
 }
 
 func (s *server) listeningAddress() net.Addr {
 	if s.listening.Load() {
-		return s.listener.Addr()
+		return s.tcpListener.Addr()
 	}
 	return nil
 }

internal/socks5/socks5.go

@@ -10,6 +10,7 @@ import (
 	"net/netip"
 	"strconv"
 	"strings"
+	"sync"
 )
 
 var (
@@ -23,6 +24,7 @@ type socksConn struct {
 	username   string
 	password   string
 	clientConn net.Conn
+	udpRouter  *udpRouter
 	logger     Logger
 }
 
@@ -109,11 +111,29 @@ func (c *socksConn) handleRequest(ctx context.Context) error {
 		c.encodeFailedResponse(c.clientConn, socksVersion, generalServerFailure)
 		return err
 	}
-	if request.command != connect {
+
+	switch request.command {
+	case connect:
+		err = c.handleConnectRequest(ctx, socksVersion, request)
+		if err != nil {
+			return fmt.Errorf("handling %s request: %w", request.command, err)
+		}
+		return nil
+	case udpAssociate:
+		err = c.handleUDPAssociateRequest(ctx, socksVersion, request)
+		if err != nil {
+			return fmt.Errorf("handling %s request: %w", request.command, err)
+		}
+		return nil
+	default:
 		c.encodeFailedResponse(c.clientConn, socksVersion, commandNotSupported)
 		return fmt.Errorf("command %s is not supported", request.command)
 	}
+}
 
+func (c *socksConn) handleConnectRequest(ctx context.Context,
+	socksVersion byte, request request,
+) error {
 	destinationAddress := net.JoinHostPort(request.destination, fmt.Sprint(request.port))
 	destinationConn, err := c.dialer.DialContext(ctx, "tcp", destinationAddress)
 	if err != nil {
@@ -176,6 +196,234 @@ func (c *socksConn) handleRequest(ctx context.Context) error {
 	}
 }
 
+func (c *socksConn) handleUDPAssociateRequest(ctx context.Context,
+	socksVersion byte, request request,
+) error {
+	expectedAddrPort, err := udpAssociateExpectedClientEndpoint(request)
+	if err != nil {
+		c.encodeFailedResponse(c.clientConn, socksVersion, addressTypeNotSupported)
+		return fmt.Errorf("deriving expected client address and port from request: %w", err)
+	}
+
+	bindAddress, bindPort, bindAddrType, err := c.udpAssociationAddresses()
+	if err != nil {
+		c.encodeFailedResponse(c.clientConn, socksVersion, generalServerFailure)
+		return fmt.Errorf("getting udp association addresses: %w", err)
+	}
+
+	association, err := c.udpRouter.registerAssociation(c.clientConn, expectedAddrPort)
+	if err != nil {
+		c.encodeFailedResponse(c.clientConn, socksVersion, generalServerFailure)
+		return fmt.Errorf("registering udp association: %w", err)
+	}
+	defer c.udpRouter.unregisterAssociation(association)
+
+	err = c.encodeSuccessResponse(c.clientConn, socksVersion, succeeded,
+		bindAddrType, bindAddress, bindPort)
+	if err != nil {
+		c.encodeFailedResponse(c.clientConn, socksVersion, generalServerFailure)
+		return fmt.Errorf("writing successful %s response: %w", udpAssociate, err)
+	}
+
+	associationCtx, associationCancel := context.WithCancel(ctx)
+	defer associationCancel()
+
+	var wg sync.WaitGroup
+
+	wg.Go(func() {
+		c.udpRouter.runAssociationHandler(associationCtx, association)
+	})
+
+	wg.Go(func() {
+		_, _ = io.Copy(io.Discard, c.clientConn)
+		associationCancel()
+	})
+	<-associationCtx.Done()
+	wg.Wait()
+	return nil
+}
+
+func udpAssociateExpectedClientEndpoint(request request) (expectedAddrPort netip.AddrPort, err error) {
+	switch request.addressType {
+	case ipv4, ipv6:
+		expectedClientAddress, parseErr := netip.ParseAddr(request.destination)
+		if parseErr != nil {
+			return netip.AddrPort{}, fmt.Errorf("parsing destination address: %w", parseErr)
+		}
+		expectedClientAddress = expectedClientAddress.Unmap()
+		if !expectedClientAddress.IsUnspecified() {
+			return netip.AddrPortFrom(expectedClientAddress, request.port), nil
+		}
+		return netip.AddrPortFrom(netip.Addr{}, request.port), nil
+	case domainName:
+		// For UDP associate, client endpoint matching is based on observed UDP source
+		// address/port. A hostname is not directly matchable at this stage, so we
+		// ignore the domain name request destination entirely.
+		return netip.AddrPortFrom(netip.Addr{}, request.port), nil
+	default:
+		return netip.AddrPort{}, fmt.Errorf("address type %d is not supported", request.addressType)
+	}
+}
+
+func (c *socksConn) udpAssociationAddresses() (bindAddress string,
+	bindPort uint16, bindAddrType addrType, err error,
+) {
+	localAddress := c.udpRouter.localAddress().String()
+	host, portString, err := net.SplitHostPort(localAddress)
+	if err != nil {
+		return "", 0, 0, fmt.Errorf("splitting local address: %w", err)
+	}
+	port, err := strconv.ParseUint(portString, 10, 16)
+	if err != nil {
+		return "", 0, 0, fmt.Errorf("parsing local port: %w", err)
+	}
+	bindAddress = host
+	bindPort = uint16(port)
+	if isUnspecifiedIPAddress(bindAddress) {
+		controlLocalAddress := c.clientConn.LocalAddr().String()
+		controlLocalHost, _, splitErr := net.SplitHostPort(controlLocalAddress)
+		if splitErr != nil {
+			return "", 0, 0, fmt.Errorf("splitting control connection local address: %w", splitErr)
+		}
+		bindAddress = controlLocalHost
+	}
+
+	ipAddress := net.ParseIP(bindAddress)
+	if ipAddress == nil {
+		bindAddrType = domainName
+		return bindAddress, bindPort, bindAddrType, nil
+	}
+
+	if ipAddress.To4() != nil {
+		bindAddrType = ipv4
+	} else {
+		bindAddrType = ipv6
+	}
+
+	return bindAddress, bindPort, bindAddrType, nil
+}
+
+func isUnspecifiedIPAddress(address string) bool {
+	ipAddress, err := netip.ParseAddr(address)
+	if err != nil {
+		return false
+	}
+	return ipAddress.IsUnspecified()
+}
+
+func decodeUDPDatagram(packet []byte) (destination string, payload []byte, err error) {
+	const minimumPacketLength = 4
+	if len(packet) < minimumPacketLength {
+		return "", nil, fmt.Errorf("packet is too short: %d", len(packet))
+	}
+	if packet[0] != 0 || packet[1] != 0 {
+		return "", nil, fmt.Errorf("reserved bytes are invalid: %x %x", packet[0], packet[1])
+	}
+	if packet[2] != 0 {
+		return "", nil, fmt.Errorf("fragmentation is not supported")
+	}
+
+	offset := 3
+	addressType := addrType(packet[offset])
+	offset++
+
+	switch addressType {
+	case ipv4:
+		const ipv4Length = 4
+		if len(packet) < offset+ipv4Length+2 {
+			return "", nil, fmt.Errorf("packet is too short for IPv4 address")
+		}
+		var ip [ipv4Length]byte
+		copy(ip[:], packet[offset:offset+ipv4Length])
+		destination = netip.AddrFrom4(ip).String()
+		offset += ipv4Length
+	case ipv6:
+		const ipv6Length = 16
+		if len(packet) < offset+ipv6Length+2 {
+			return "", nil, fmt.Errorf("packet is too short for IPv6 address")
+		}
+		var ip [ipv6Length]byte
+		copy(ip[:], packet[offset:offset+ipv6Length])
+		destination = netip.AddrFrom16(ip).String()
+		offset += ipv6Length
+	case domainName:
+		if len(packet) < offset+1 {
+			return "", nil, fmt.Errorf("packet is too short for domain name length")
+		}
+		domainNameLength := int(packet[offset])
+		offset++
+		if len(packet) < offset+domainNameLength+2 {
+			return "", nil, fmt.Errorf("packet is too short for domain name")
+		}
+		destination = string(packet[offset : offset+domainNameLength])
+		offset += domainNameLength
+	default:
+		return "", nil, fmt.Errorf("address type is not supported: %d", addressType)
+	}
+
+	port := binary.BigEndian.Uint16(packet[offset : offset+2])
+	destination = net.JoinHostPort(destination, fmt.Sprint(port))
+	offset += 2
+	payload = packet[offset:]
+
+	return destination, payload, nil
+}
+
+func encodeUDPDatagramToBuffer(writer io.Writer, sourceAddrPort netip.AddrPort,
+	payload []byte,
+) error {
+	address := sourceAddrPort.Addr()
+	if !address.IsValid() {
+		return errors.New("source address is not valid")
+	}
+
+	err := writeUDPDatagramSourceAddress(writer, address)
+	if err != nil {
+		return fmt.Errorf("writing source address: %w", err)
+	}
+
+	var portBytes [2]byte
+	binary.BigEndian.PutUint16(portBytes[:], sourceAddrPort.Port())
+	_, err = writer.Write(portBytes[:])
+	if err != nil {
+		return fmt.Errorf("writing destination port: %w", err)
+	}
+
+	_, err = writer.Write(payload)
+	if err != nil {
+		return fmt.Errorf("writing payload: %w", err)
+	}
+
+	return nil
+}
+
+func writeUDPDatagramSourceAddress(writer io.Writer, address netip.Addr) error {
+	var addrType addrType
+	var addressBytes []byte
+	switch {
+	case address.Is4():
+		addrType = ipv4
+		array := address.As4()
+		addressBytes = array[:]
+	case address.Is6():
+		addrType = ipv6
+		array := address.As16()
+		addressBytes = array[:]
+	default:
+		return fmt.Errorf("address type is not supported: %v", address)
+	}
+
+	_, err := writer.Write([]byte{0, 0, 0, byte(addrType)})
+	if err != nil {
+		return fmt.Errorf("writing header: %w", err)
+	}
+	_, err = writer.Write(addressBytes)
+	if err != nil {
+		return fmt.Errorf("writing IP address: %w", err)
+	}
+	return nil
+}
+
 // See https://datatracker.ietf.org/doc/html/rfc1928#section-3
 func verifyFirstNegotiation(reader io.Reader, requiredMethod authMethod) error {
 	const headerLength = 2 // version + nMethods bytes

internal/socks5/socks5_test.go

@@ -2,9 +2,13 @@ package socks5
 
 import (
 	"bytes"
+	"context"
 	"encoding/binary"
+	"errors"
+	"fmt"
 	"io"
 	"net"
+	"net/netip"
 	"strconv"
 	"strings"
 	"testing"
@@ -96,6 +100,178 @@ func TestServerProxy(t *testing.T) {
 	}
 }
 
+func TestServerProxyTCPAndUDPParallel(t *testing.T) {
+	t.Parallel()
+	testCases := map[string]struct {
+		username string
+		password string
+	}{
+		"no_auth": {},
+		"with_auth": {
+			username: "user",
+			password: "pass",
+		},
+	}
+
+	for name, testCase := range testCases {
+		t.Run(name, func(t *testing.T) {
+			t.Parallel()
+
+			backendTCPListener, err := (&net.ListenConfig{}).Listen(t.Context(), "tcp", "127.0.0.1:0")
+			require.NoError(t, err)
+
+			backendTCPConnChannel := make(chan net.Conn, 1)
+			go func() {
+				connection, err := backendTCPListener.Accept()
+				if err != nil {
+					return
+				}
+				backendTCPConnChannel <- connection
+			}()
+
+			backendUDPPacketConn, err := (&net.ListenConfig{}).ListenPacket(t.Context(), "udp", "127.0.0.1:0")
+			require.NoError(t, err)
+
+			server := newServer(Settings{
+				Username: testCase.username,
+				Password: testCase.password,
+				Address:  "127.0.0.1:0",
+				Logger:   noopLogger{},
+			})
+			_, err = server.Start(t.Context())
+			require.NoError(t, err)
+			t.Cleanup(func() {
+				_ = server.Stop()
+				_ = backendTCPListener.Close()
+				_ = backendUDPPacketConn.Close()
+			})
+
+			clientTCPConn := dialSOCKS5(t, server.listeningAddress().String(),
+				backendTCPListener.Addr().String(), testCase.username, testCase.password)
+			defer clientTCPConn.Close()
+
+			backendTCPConn := <-backendTCPConnChannel
+			defer backendTCPConn.Close()
+
+			udpControlConn, clientUDPConn := dialSOCKS5UDPAssociate(t,
+				server.listeningAddress().String(), testCase.username, testCase.password)
+			defer udpControlConn.Close()
+			defer clientUDPConn.Close()
+
+			tcpErrCh := make(chan error, 1)
+			go func() {
+				tcpErrCh <- runTCPProxyRoundTrip(clientTCPConn, backendTCPConn)
+			}()
+
+			udpErrCh := make(chan error, 1)
+			go func() {
+				udpErrCh <- runUDPProxyRoundTrip(t.Context(), clientUDPConn, backendUDPPacketConn)
+			}()
+
+			err = <-tcpErrCh
+			require.NoError(t, err)
+			err = <-udpErrCh
+			require.NoError(t, err)
+		})
+	}
+}
+
+func runTCPProxyRoundTrip(clientTCPConn net.Conn, backendTCPConn net.Conn) error {
+	clientMessage := []byte("hello from client")
+	_, err := clientTCPConn.Write(clientMessage)
+	if err != nil {
+		return err
+	}
+
+	received := make([]byte, len(clientMessage))
+	_, err = io.ReadFull(backendTCPConn, received)
+	if err != nil {
+		return err
+	}
+	if !bytes.Equal(clientMessage, received) {
+		return errors.New("backend did not receive expected TCP payload")
+	}
+
+	backendMessage := []byte("hello from backend")
+	_, err = backendTCPConn.Write(backendMessage)
+	if err != nil {
+		return err
+	}
+
+	receivedByClient := make([]byte, len(backendMessage))
+	_, err = io.ReadFull(clientTCPConn, receivedByClient)
+	if err != nil {
+		return err
+	}
+	if !bytes.Equal(backendMessage, receivedByClient) {
+		return errors.New("client did not receive expected TCP payload")
+	}
+
+	return nil
+}
+
+func runUDPProxyRoundTrip(ctx context.Context, clientUDPConn *net.UDPConn, backendUDPPacketConn net.PacketConn) error {
+	udpPayload := []byte("hello from udp client")
+	udpRequest, err := makeSOCKS5UDPDatagram(backendUDPPacketConn.LocalAddr().String(), udpPayload)
+	if err != nil {
+		return err
+	}
+
+	_, err = clientUDPConn.Write(udpRequest)
+	if err != nil {
+		return err
+	}
+
+	deadline, hasDeadline := ctx.Deadline()
+	if hasDeadline {
+		err = backendUDPPacketConn.SetReadDeadline(deadline)
+		if err != nil {
+			return fmt.Errorf("setting read deadline on backend connection: %w", err)
+		}
+	}
+	const bufferSize = 512
+	backendReadBuffer := make([]byte, bufferSize)
+	packetLength, proxyAddress, err := backendUDPPacketConn.ReadFrom(backendReadBuffer)
+	if err != nil {
+		return err
+	}
+	if !bytes.Equal(udpPayload, backendReadBuffer[:packetLength]) {
+		return errors.New("backend did not receive expected UDP payload")
+	}
+
+	backendUDPReply := []byte("hello from udp backend")
+	_, err = backendUDPPacketConn.WriteTo(backendUDPReply, proxyAddress)
+	if err != nil {
+		return err
+	}
+
+	if hasDeadline {
+		err = clientUDPConn.SetReadDeadline(deadline)
+		if err != nil {
+			return fmt.Errorf("setting read deadline on client connection: %w", err)
+		}
+	}
+	udpResponseBuffer := make([]byte, 1024)
+	responseLength, err := clientUDPConn.Read(udpResponseBuffer)
+	if err != nil {
+		return err
+	}
+
+	destinationAddress, udpResponsePayload, err := parseSOCKS5UDPDatagram(udpResponseBuffer[:responseLength])
+	if err != nil {
+		return err
+	}
+
+	if !bytes.Equal(backendUDPReply, udpResponsePayload) {
+		return errors.New("client did not receive expected UDP payload")
+	}
+	if destinationAddress != backendUDPPacketConn.LocalAddr().String() {
+		return errors.New("udp response destination address mismatch")
+	}
+
+	return nil
+}
+
 // dialSOCKS5 performs the full SOCKS5 handshake (with optional username/password
 // subnegotiation) and returns a connected net.Conn ready for data exchange.
 func dialSOCKS5(t *testing.T, proxyAddr, targetAddr, username, password string) net.Conn {
@@ -109,6 +285,55 @@ func dialSOCKS5(t *testing.T, proxyAddr, targetAddr, username, password string)
 	conn, err := (&net.Dialer{}).DialContext(t.Context(), "tcp", proxyAddr)
 	require.NoError(t, err)
 
+	negotiateSOCKS5(t, conn, username, password)
+
+	var connectRequest []byte
+	if ip := net.ParseIP(host).To4(); ip != nil {
+		connectRequest = []byte{socks5Version, byte(connect), 0, byte(ipv4)}
+		connectRequest = append(connectRequest, ip...)
+	} else {
+		connectRequest = []byte{socks5Version, byte(connect), 0, byte(domainName), byte(len(host))}
+		connectRequest = append(connectRequest, []byte(host)...)
+	}
+	connectRequest = binary.BigEndian.AppendUint16(connectRequest, uint16(targetPort)) //nolint:gosec
+	_, err = conn.Write(connectRequest)
+	require.NoError(t, err)
+
+	_, err = readSOCKS5ResponseAddress(t, conn)
+	require.NoError(t, err)
+
+	return conn
+}
+
+func dialSOCKS5UDPAssociate(t *testing.T, proxyAddr, username, password string) (net.Conn, *net.UDPConn) {
+	t.Helper()
+
+	controlConn, err := (&net.Dialer{}).DialContext(t.Context(), "tcp", proxyAddr)
+	require.NoError(t, err)
+
+	negotiateSOCKS5(t, controlConn, username, password)
+
+	udpAssociateRequest := []byte{socks5Version, byte(udpAssociate), 0, byte(ipv4), 0, 0, 0, 0, 0, 0}
+	_, err = controlConn.Write(udpAssociateRequest)
+	require.NoError(t, err)
+
+	udpProxyAddress, err := readSOCKS5ResponseAddress(t, controlConn)
+	require.NoError(t, err)
+
+	udpProxyResolvedAddress, err := net.ResolveUDPAddr("udp", udpProxyAddress)
+	require.NoError(t, err)
+
+	udpConn, err := net.DialUDP("udp", nil, udpProxyResolvedAddress)
+	require.NoError(t, err)
+
+	return controlConn, udpConn
+}
+
+func negotiateSOCKS5(t *testing.T, conn net.Conn, username, password string) {
+	t.Helper()
+
+	var err error
+
 	var method authMethod
 	if username != "" || password != "" {
 		method = authUsernamePassword
@@ -138,45 +363,146 @@ func dialSOCKS5(t *testing.T, proxyAddr, targetAddr, username, password string)
 		require.Equal(t, authUsernamePasswordSubNegotiation1, subnegResp[0])
 		require.Equal(t, byte(0), subnegResp[1])
 	}
+}
 
-	var connectRequest []byte
-	if ip := net.ParseIP(host).To4(); ip != nil {
-		connectRequest = []byte{socks5Version, byte(connect), 0, byte(ipv4)}
-		connectRequest = append(connectRequest, ip...)
-	} else {
-		connectRequest = []byte{socks5Version, byte(connect), 0, byte(domainName), byte(len(host))}
-		connectRequest = append(connectRequest, []byte(host)...)
-	}
-	connectRequest = binary.BigEndian.AppendUint16(connectRequest, uint16(targetPort)) //nolint:gosec
-	_, err = conn.Write(connectRequest)
-	require.NoError(t, err)
+func readSOCKS5ResponseAddress(t *testing.T, conn net.Conn) (address string, err error) {
+	t.Helper()
 
 	var responseHeader [4]byte
 	_, err = io.ReadFull(conn, responseHeader[:])
-	require.NoError(t, err)
-	require.Equal(t, socks5Version, responseHeader[0])
-	require.Equal(t, byte(succeeded), responseHeader[1])
-
-	// Consume BND.ADDR and BND.PORT (their values are irrelevant to the caller).
-	switch addrType(responseHeader[3]) {
-	case ipv4:
-		var addrPort [net.IPv4len + 2]byte
-		_, err = io.ReadFull(conn, addrPort[:])
-		require.NoError(t, err)
-	case ipv6:
-		var addrPort [net.IPv6len + 2]byte
-		_, err = io.ReadFull(conn, addrPort[:])
-		require.NoError(t, err)
-	case domainName:
-		var lenBuf [1]byte
-		_, err = io.ReadFull(conn, lenBuf[:])
-		require.NoError(t, err)
-		addrPort := make([]byte, int(lenBuf[0])+2)
-		_, err = io.ReadFull(conn, addrPort)
-		require.NoError(t, err)
+	if err != nil {
+		return "", err
+	}
+	if responseHeader[0] != socks5Version {
+		return "", errors.New("version mismatch")
+	}
+	if responseHeader[1] != byte(succeeded) {
+		return "", errors.New("request was not successful")
 	}
 
-	return conn
+	var host string
+	switch addrType(responseHeader[3]) {
+	case ipv4:
+		addressAndPort := make([]byte, net.IPv4len+2)
+		_, err = io.ReadFull(conn, addressAndPort)
+		if err != nil {
+			return "", err
+		}
+		host = net.IP(addressAndPort[:net.IPv4len]).String()
+		port := binary.BigEndian.Uint16(addressAndPort[net.IPv4len:])
+		return net.JoinHostPort(host, strconv.FormatUint(uint64(port), 10)), nil
+	case ipv6:
+		addressAndPort := make([]byte, net.IPv6len+2)
+		_, err = io.ReadFull(conn, addressAndPort)
+		if err != nil {
+			return "", err
+		}
+		host = net.IP(addressAndPort[:net.IPv6len]).String()
+		port := binary.BigEndian.Uint16(addressAndPort[net.IPv6len:])
+		return net.JoinHostPort(host, strconv.FormatUint(uint64(port), 10)), nil
+	case domainName:
+		var lengthBuffer [1]byte
+		_, err = io.ReadFull(conn, lengthBuffer[:])
+		if err != nil {
+			return "", err
+		}
+		domainAndPort := make([]byte, int(lengthBuffer[0])+2)
+		_, err = io.ReadFull(conn, domainAndPort)
+		if err != nil {
+			return "", err
+		}
+		host = string(domainAndPort[:len(domainAndPort)-2])
+		port := binary.BigEndian.Uint16(domainAndPort[len(domainAndPort)-2:])
+		return net.JoinHostPort(host, strconv.FormatUint(uint64(port), 10)), nil
+	default:
+		return "", errors.New("unknown address type")
+	}
+}
+
+func makeSOCKS5UDPDatagram(targetAddress string, payload []byte) ([]byte, error) {
+	host, portString, err := net.SplitHostPort(targetAddress)
+	if err != nil {
+		return nil, err
+	}
+	port, err := strconv.ParseUint(portString, 10, 16)
+	if err != nil {
+		return nil, err
+	}
+
+	datagram := []byte{0, 0, 0}
+	ipAddress := net.ParseIP(host)
+	if ipAddress != nil {
+		if ipAddress.To4() != nil {
+			datagram = append(datagram, byte(ipv4))
+			datagram = append(datagram, ipAddress.To4()...)
+		} else {
+			datagram = append(datagram, byte(ipv6))
+			datagram = append(datagram, ipAddress.To16()...)
+		}
+	} else {
+		if len(host) > 255 {
+			return nil, errors.New("domain name too long")
+		}
+		datagram = append(datagram, byte(domainName), byte(len(host)))
+		datagram = append(datagram, []byte(host)...)
+	}
+	datagram = binary.BigEndian.AppendUint16(datagram, uint16(port))
+	datagram = append(datagram, payload...)
+
+	return datagram, nil
+}
+
+func parseSOCKS5UDPDatagram(datagram []byte) (destinationAddress string, payload []byte, err error) {
+	if len(datagram) < 4 {
+		return "", nil, errors.New("datagram too short")
+	}
+	if datagram[0] != 0 || datagram[1] != 0 {
+		return "", nil, errors.New("invalid reserved header")
+	}
+	if datagram[2] != 0 {
+		return "", nil, errors.New("fragments are not supported")
+	}
+
+	offset := 3
+	var host string
+	switch addrType(datagram[offset]) {
+	case ipv4:
+		offset++
+		if len(datagram) < offset+net.IPv4len+2 {
+			return "", nil, errors.New("datagram too short for IPv4")
+		}
+		host = net.IP(datagram[offset : offset+net.IPv4len]).String()
+		offset += net.IPv4len
+	case ipv6:
+		offset++
+		if len(datagram) < offset+net.IPv6len+2 {
+			return "", nil, errors.New("datagram too short for IPv6")
+		}
+		host = net.IP(datagram[offset : offset+net.IPv6len]).String()
+		offset += net.IPv6len
+	case domainName:
+		offset++
+		if len(datagram) < offset+1 {
+			return "", nil, errors.New("datagram too short for domain length")
+		}
+		domainLength := int(datagram[offset])
+		offset++
+		if len(datagram) < offset+domainLength+2 {
+			return "", nil, errors.New("datagram too short for domain")
+		}
+		host = string(datagram[offset : offset+domainLength])
+		offset += domainLength
+	default:
+		return "", nil, errors.New("unknown address type")
+	}
+
+	if len(datagram) < offset+2 {
+		return "", nil, errors.New("datagram too short for port")
+	}
+	port := binary.BigEndian.Uint16(datagram[offset : offset+2])
+	offset += 2
+
+	return net.JoinHostPort(host, strconv.FormatUint(uint64(port), 10)), datagram[offset:], nil
 }
 
 func Test_newServer(t *testing.T) {
@@ -224,7 +550,8 @@ func Test_Server_StartStop(t *testing.T) {
 	ctrl := gomock.NewController(t)
 
 	logger := NewMockLogger(ctrl)
-	logger.EXPECT().Infof("SOCKS5 server listening on %s", gomock.Any())
+	logger.EXPECT().Infof("SOCKS5 TCP server listening on %s", gomock.Any())
+	logger.EXPECT().Infof("SOCKS5 UDP server listening on %s", gomock.Any())
 
 	server := newServer(Settings{
 		Address: "127.0.0.1:0",
@@ -377,6 +704,70 @@ func Test_decodeRequest(t *testing.T) {
 	}
 }
 
+func Test_udpAssociateExpectedClientEndpoint(t *testing.T) {
+	t.Parallel()
+
+	testCases := map[string]struct {
+		request     request
+		expected    netip.AddrPort
+		expectedErr string
+	}{
+		"ipv4_endpoint": {
+			request: request{
+				addressType: ipv4,
+				destination: "192.0.2.10",
+				port:        5555,
+			},
+			expected: netip.MustParseAddrPort("192.0.2.10:5555"),
+		},
+		"ipv4_unspecified_address": {
+			request: request{
+				addressType: ipv4,
+				destination: "0.0.0.0",
+				port:        6000,
+			},
+			expected: netip.AddrPortFrom(netip.Addr{}, 6000),
+		},
+		"domain_name_with_port": {
+			request: request{
+				addressType: domainName,
+				destination: "client.example",
+				port:        7000,
+			},
+			expected: netip.AddrPortFrom(netip.Addr{}, 7000),
+		},
+		"domain_name_without_port": {
+			request: request{
+				addressType: domainName,
+				destination: "client.example",
+			},
+			expected: netip.AddrPort{},
+		},
+		"unsupported_address_type": {
+			request: request{
+				addressType: 255,
+			},
+			expectedErr: "address type 255 is not supported",
+		},
+	}
+
+	for name, testCase := range testCases {
+		t.Run(name, func(t *testing.T) {
+			t.Parallel()
+
+			result, err := udpAssociateExpectedClientEndpoint(testCase.request)
+
+			if testCase.expectedErr != "" {
+				assert.ErrorContains(t, err, testCase.expectedErr)
+				return
+			}
+
+			assert.NoError(t, err)
+			assert.Equal(t, testCase.expected, result)
+		})
+	}
+}
+
 func Test_verifyFirstNegotiation(t *testing.T) {
 	t.Parallel()
 	testCases := map[string]struct {
@@ -598,10 +989,6 @@ func Test_cmdType_String(t *testing.T) {
 			cmd:          connect,
 			expectedName: "connect",
 		},
-		"bind": {
-			cmd:          bind,
-			expectedName: "bind",
-		},
 		"udp_associate": {
 			cmd:          udpAssociate,
 			expectedName: "UDP associate",
@@ -620,3 +1007,80 @@ func Test_cmdType_String(t *testing.T) {
 		})
 	}
 }
+
+func Test_socksConn_udpAssociationAddresses(t *testing.T) {
+	t.Parallel()
+
+	testCases := map[string]struct {
+		routerAddress         string
+		expectAddressFromConn bool
+		expectedAddress       string
+	}{
+		"wildcard_router_address_uses_control_connection_local_ip": {
+			routerAddress:         ":0",
+			expectAddressFromConn: true,
+		},
+		"concrete_router_address_is_kept": {
+			routerAddress:   "127.0.0.1:0",
+			expectedAddress: "127.0.0.1",
+		},
+	}
+
+	for name, testCase := range testCases {
+		t.Run(name, func(t *testing.T) {
+			t.Parallel()
+
+			router, err := newUDPRouter(t.Context(), testCase.routerAddress, noopLogger{})
+			require.NoError(t, err)
+			t.Cleanup(func() {
+				err := router.close()
+				assert.NoError(t, err)
+			})
+
+			controlListener, err := (&net.ListenConfig{}).Listen(t.Context(), "tcp", "127.0.0.1:0")
+			require.NoError(t, err)
+			t.Cleanup(func() {
+				err := controlListener.Close()
+				assert.NoError(t, err)
+			})
+
+			acceptedConnCh := make(chan net.Conn, 1)
+			go func() {
+				acceptedConn, acceptErr := controlListener.Accept()
+				if acceptErr != nil {
+					return
+				}
+				acceptedConnCh <- acceptedConn
+			}()
+
+			clientControlConn, err := (&net.Dialer{}).DialContext(t.Context(), "tcp", controlListener.Addr().String())
+			require.NoError(t, err)
+			defer clientControlConn.Close()
+
+			serverControlConn := <-acceptedConnCh
+			defer serverControlConn.Close()
+
+			socksConnection := &socksConn{
+				clientConn: clientControlConn,
+				udpRouter:  router,
+			}
+			bindAddress, bindPort, bindAddrType, err := socksConnection.udpAssociationAddresses()
+			require.NoError(t, err)
+
+			if testCase.expectAddressFromConn {
+				clientLocalHost, _, err := net.SplitHostPort(clientControlConn.LocalAddr().String())
+				require.NoError(t, err)
+				assert.Equal(t, clientLocalHost, bindAddress)
+			} else {
+				assert.Equal(t, testCase.expectedAddress, bindAddress)
+			}
+
+			_, routerPortString, err := net.SplitHostPort(router.localAddress().String())
+			require.NoError(t, err)
+			routerPort, err := strconv.ParseUint(routerPortString, 10, 16)
+			require.NoError(t, err)
+			assert.Equal(t, uint16(routerPort), bindPort)
+			assert.Equal(t, ipv4, bindAddrType)
+		})
+	}
+}

internal/socks5/udp_router.go

@@ -0,0 +1,370 @@
+package socks5
+
+import (
+	"bytes"
+	"context"
+	"errors"
+	"fmt"
+	"net"
+	"net/netip"
+	"sync"
+)
+
+type udpAssociation struct {
+	id               uint64
+	clientAddrPort   netip.AddrPort
+	expectedAddrPort netip.AddrPort
+	controlConnAddr  netip.Addr
+	packetCh         chan *bytes.Buffer
+}
+
+type udpRouter struct {
+	logger Logger
+
+	listener                      net.PacketConn
+	mutex                         sync.Mutex
+	bufferPool                    sync.Pool
+	nextAssociationID             uint64
+	clientAddrPortToAssociation   map[netip.AddrPort]udpAssociation
+	clientIPToPendingAssociations map[netip.Addr][]udpAssociation
+	associationIDToClientAddrPort map[uint64]netip.AddrPort
+}
+
+const (
+	maxUDPPacketLength            = 65535
+	maxSOCKS5UDPDatagramOverhead  = 3 + 1 + 16 + 2
+	pooledUDPPacketBufferCapacity = maxUDPPacketLength + maxSOCKS5UDPDatagramOverhead
+)
+
+func newUDPRouter(ctx context.Context, address string, logger Logger) (router *udpRouter, err error) {
+	config := &net.ListenConfig{}
+	listener, err := config.ListenPacket(ctx, "udp", address)
+	if err != nil {
+		return nil, fmt.Errorf("UDP listening: %w", err)
+	}
+
+	return &udpRouter{
+		logger:   logger,
+		listener: listener,
+		bufferPool: sync.Pool{
+			New: func() any {
+				return bytes.NewBuffer(make([]byte, 0, pooledUDPPacketBufferCapacity))
+			},
+		},
+		nextAssociationID:             1,
+		clientAddrPortToAssociation:   make(map[netip.AddrPort]udpAssociation),
+		clientIPToPendingAssociations: make(map[netip.Addr][]udpAssociation),
+		associationIDToClientAddrPort: make(map[uint64]netip.AddrPort),
+	}, nil
+}
+
+func (r *udpRouter) localAddress() net.Addr {
+	return r.listener.LocalAddr()
+}
+
+func (r *udpRouter) close() error {
+	return r.listener.Close()
+}
+
+func (r *udpRouter) registerAssociation(controlConn net.Conn, expectedAddrPort netip.AddrPort) (udpAssociation, error) {
+	controlConnAddrPort, err := netip.ParseAddrPort(controlConn.RemoteAddr().String())
+	if err != nil {
+		return udpAssociation{}, fmt.Errorf("parsing control connection address: %w", err)
+	}
+	controlConnAddr := controlConnAddrPort.Addr().Unmap()
+
+	r.mutex.Lock()
+	defer r.mutex.Unlock()
+
+	const udpPacketChannelBuffer = 2
+	associationID := r.nextAssociationID
+	r.nextAssociationID++
+
+	association := udpAssociation{
+		id:               associationID,
+		expectedAddrPort: expectedAddrPort,
+		controlConnAddr:  controlConnAddr,
+		packetCh:         make(chan *bytes.Buffer, udpPacketChannelBuffer),
+	}
+
+	if expectedAddrPort.Addr().IsValid() && expectedAddrPort.Port() != 0 {
+		association.clientAddrPort = expectedAddrPort
+		r.clientAddrPortToAssociation[association.clientAddrPort] = association
+		r.associationIDToClientAddrPort[association.id] = association.clientAddrPort
+		return association, nil
+	}
+
+	pendingAssociations := r.clientIPToPendingAssociations[controlConnAddr]
+	pendingAssociations = append(pendingAssociations, association)
+	r.clientIPToPendingAssociations[controlConnAddr] = pendingAssociations
+
+	return association, nil
+}
+
+func (r *udpRouter) unregisterAssociation(association udpAssociation) {
+	r.mutex.Lock()
+	defer r.mutex.Unlock()
+
+	clientAddrPort, hasClientAddress := r.associationIDToClientAddrPort[association.id]
+	if hasClientAddress {
+		delete(r.associationIDToClientAddrPort, association.id)
+		delete(r.clientAddrPortToAssociation, clientAddrPort)
+	}
+
+	pendingAssociations := r.clientIPToPendingAssociations[association.controlConnAddr]
+	for i, pendingAssociation := range pendingAssociations {
+		if pendingAssociation.id == association.id {
+			pendingAssociations = append(pendingAssociations[:i], pendingAssociations[i+1:]...)
+			break
+		}
+	}
+	if len(pendingAssociations) == 0 {
+		delete(r.clientIPToPendingAssociations, association.controlConnAddr)
+	} else {
+		r.clientIPToPendingAssociations[association.controlConnAddr] = pendingAssociations
+	}
+}
+
+func (r *udpRouter) run(ctx context.Context) error {
+	packetBuffer := make([]byte, maxUDPPacketLength)
+
+	for {
+		packetLength, sourceAddress, err := r.listener.ReadFrom(packetBuffer)
+		if err != nil {
+			if ctx.Err() != nil && errors.Is(err, net.ErrClosed) {
+				return nil
+			}
+			return fmt.Errorf("reading UDP packet: %w", err)
+		}
+
+		sourceAddrPort, err := netAddrToNetipAddrPort(sourceAddress)
+		if err != nil {
+			r.logger.Warnf("parsing source address: %s", err)
+			continue
+		}
+		buffer := r.bufferPool.Get().(*bytes.Buffer) //nolint:forcetypeassert
+		buffer.Reset()
+		_, err = buffer.Write(packetBuffer[:packetLength])
+		if err != nil {
+			r.bufferPool.Put(buffer)
+			r.logger.Warnf("buffering packet: %s", err)
+			continue
+		}
+		err = r.routePacket(sourceAddrPort, buffer)
+		if err != nil {
+			r.logger.Warnf("failed routing UDP packet: %s", err)
+		}
+	}
+}
+
+func (r *udpRouter) routePacket(sourceAddrPort netip.AddrPort, packet *bytes.Buffer) error {
+	r.mutex.Lock()
+	association, packetFromClient := r.findClientAssociation(sourceAddrPort)
+	r.mutex.Unlock()
+
+	if !packetFromClient {
+		r.bufferPool.Put(packet)
+		return nil
+	}
+
+	select {
+	case association.packetCh <- packet:
+		return nil
+	default:
+		r.bufferPool.Put(packet)
+		return errors.New("association packet queue full")
+	}
+}
+
+func (r *udpRouter) findClientAssociation(sourceAddrPort netip.AddrPort) (
+	association udpAssociation, ok bool,
+) {
+	association, ok = r.clientAddrPortToAssociation[sourceAddrPort]
+	if ok {
+		return association, true
+	}
+	sourceAddr := sourceAddrPort.Addr()
+
+	pendingAssociations := r.clientIPToPendingAssociations[sourceAddr]
+	if len(pendingAssociations) == 0 {
+		return udpAssociation{}, false
+	}
+
+	index := -1
+	for i, pendingAssociation := range pendingAssociations {
+		if matchesExpectedClientEndpoint(pendingAssociation, sourceAddrPort) {
+			association = pendingAssociation
+			index = i
+			break
+		}
+	}
+	if index == -1 {
+		return udpAssociation{}, false
+	}
+
+	r.clientIPToPendingAssociations[sourceAddr] = append(pendingAssociations[:index], pendingAssociations[index+1:]...)
+	if len(r.clientIPToPendingAssociations[sourceAddr]) == 0 {
+		delete(r.clientIPToPendingAssociations, sourceAddr)
+	}
+
+	association.clientAddrPort = sourceAddrPort
+	r.clientAddrPortToAssociation[sourceAddrPort] = association
+	r.associationIDToClientAddrPort[association.id] = sourceAddrPort
+
+	return association, true
+}
+
+func matchesExpectedClientEndpoint(association udpAssociation, sourceAddrPort netip.AddrPort) bool {
+	switch {
+	case association.expectedAddrPort.Addr().IsValid() && sourceAddrPort.Addr() != association.expectedAddrPort.Addr():
+		return false
+	case association.expectedAddrPort.Port() != 0 && sourceAddrPort.Port() != association.expectedAddrPort.Port():
+		return false
+	}
+	return true
+}
+
+func (r *udpRouter) clientAddrPortForAssociation(associationID uint64) (
+	clientAddrPort netip.AddrPort, ok bool,
+) {
+	r.mutex.Lock()
+	defer r.mutex.Unlock()
+
+	clientAddrPort, ok = r.associationIDToClientAddrPort[associationID]
+	return clientAddrPort, ok
+}
+
+func (r *udpRouter) runAssociationHandler(ctx context.Context, association udpAssociation) {
+	config := &net.ListenConfig{}
+	socket, err := config.ListenPacket(ctx, "udp", ":0")
+	if err != nil {
+		r.logger.Warnf("creating per-association UDP socket: %s", err)
+		return
+	}
+	defer socket.Close()
+
+	go closeSocketOnContextDone(ctx, socket)
+
+	packetBuffer := make([]byte, maxUDPPacketLength)
+
+	forwardDoneCh := make(chan struct{})
+	go r.forwardClientPackets(ctx, socket, association.packetCh, forwardDoneCh)
+
+	for {
+		packetLength, sourceAddress, err := socket.ReadFrom(packetBuffer)
+		if err != nil {
+			if ctx.Err() != nil || errors.Is(err, net.ErrClosed) {
+				<-forwardDoneCh
+				return
+			}
+			r.logger.Warnf("reading from per-association UDP socket: %s", err)
+			continue
+		}
+
+		sourceAddrPort, err := netAddrToNetipAddrPort(sourceAddress)
+		if err != nil {
+			r.logger.Warnf("parsing source address from destination: %s", err)
+			continue
+		}
+
+		buffer := r.bufferPool.Get().(*bytes.Buffer) //nolint:forcetypeassert
+		buffer.Reset()
+		err = encodeUDPDatagramToBuffer(buffer, sourceAddrPort, packetBuffer[:packetLength])
+		if err != nil {
+			r.bufferPool.Put(buffer)
+			r.logger.Warnf("encoding response datagram: %s", err)
+			continue
+		}
+
+		clientAddrPort, found := r.clientAddrPortForAssociation(association.id)
+		if !found {
+			r.bufferPool.Put(buffer)
+			r.logger.Warnf("client address not found for association id %d", association.id)
+			continue
+		}
+
+		clientUDPAddress := &net.UDPAddr{
+			IP:   clientAddrPort.Addr().AsSlice(),
+			Port: int(clientAddrPort.Port()),
+		}
+		_, err = r.listener.WriteTo(buffer.Bytes(), clientUDPAddress)
+		r.bufferPool.Put(buffer)
+		if err != nil {
+			r.logger.Warnf("writing response to client: %s", err)
+		}
+	}
+}
+
+func closeSocketOnContextDone(ctx context.Context, socket net.PacketConn) {
+	<-ctx.Done()
+	_ = socket.Close()
+}
+
+func (r *udpRouter) forwardClientPackets(ctx context.Context, socket net.PacketConn,
+	packetCh <-chan *bytes.Buffer, done chan<- struct{},
+) {
+	defer close(done)
+
+	for {
+		select {
+		case <-ctx.Done():
+			return
+		case buffer, ok := <-packetCh:
+			if !ok {
+				return
+			}
+
+			err := r.writeClientPacketToDestination(ctx, socket, buffer)
+			r.bufferPool.Put(buffer)
+			if err != nil {
+				r.logger.Warnf("forwarding client packet to destination: %s", err)
+			}
+		}
+	}
+}
+
+func (r *udpRouter) writeClientPacketToDestination(ctx context.Context,
+	socket net.PacketConn, packet *bytes.Buffer,
+) error {
+	destination, payload, err := decodeUDPDatagram(packet.Bytes())
+	if err != nil {
+		return fmt.Errorf("decoding UDP datagram: %w", err)
+	}
+
+	host, portStr, err := net.SplitHostPort(destination)
+	if err != nil {
+		return fmt.Errorf("splitting destination host and port: %w", err)
+	}
+
+	if _, err := netip.ParseAddr(host); err != nil { // domain name
+		addrs, err := net.DefaultResolver.LookupHost(ctx, host)
+		if err != nil {
+			return fmt.Errorf("resolving destination host: %w", err)
+		}
+		if len(addrs) == 0 {
+			return fmt.Errorf("resolving destination host: no addresses found for %q", host)
+		}
+
+		destination = net.JoinHostPort(addrs[0], portStr)
+	}
+
+	resolvedDestinationUDPAddress, err := net.ResolveUDPAddr("udp", destination)
+	if err != nil {
+		return fmt.Errorf("resolving destination UDP address: %w", err)
+	}
+
+	_, err = socket.WriteTo(payload, resolvedDestinationUDPAddress)
+	if err != nil && ctx.Err() == nil {
+		return fmt.Errorf("writing payload to destination: %w", err)
+	}
+
+	return nil
+}
+
+func netAddrToNetipAddrPort(addr net.Addr) (netip.AddrPort, error) {
+	addrPort, err := netip.ParseAddrPort(addr.String())
+	if err != nil {
+		return netip.AddrPort{}, fmt.Errorf("parsing address: %w", err)
+	}
+	return netip.AddrPortFrom(addrPort.Addr().Unmap(), addrPort.Port()), nil
+}

internal/socks5/udp_router_integration_test.go

@@ -0,0 +1,164 @@
+//go:build integration
+
+package socks5
+
+import (
+	"bytes"
+	"context"
+	"math/rand/v2"
+	"net"
+	"net/netip"
+	"strconv"
+	"testing"
+	"time"
+
+	"github.com/golang/mock/gomock"
+	"github.com/miekg/dns"
+	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
+)
+
+func Test_udpRouter_ResolveGithubFromCloudflareDNS(t *testing.T) {
+	t.Parallel()
+
+	ctx := t.Context()
+	var cancel context.CancelFunc
+	deadline, hasDeadline := ctx.Deadline()
+	if hasDeadline {
+		const deadlineBuffer = 500 * time.Millisecond
+		deadline = deadline.Add(-deadlineBuffer)
+	} else {
+		const defaultTimeout = 10 * time.Second
+		deadline = time.Now().Add(defaultTimeout)
+	}
+	ctx, cancel = context.WithDeadline(ctx, deadline)
+
+	ctrl := gomock.NewController(t)
+	logger := NewMockLogger(ctrl)
+
+	router, err := newUDPRouter(ctx, "127.0.0.1:0", logger)
+	require.NoError(t, err)
+
+	routerRunErrCh := make(chan error)
+	go func() {
+		routerRunErrCh <- router.run(ctx)
+	}()
+
+	t.Cleanup(func() {
+		cancel()
+		err := router.close()
+		assert.NoError(t, err, "closing router")
+		runErr := <-routerRunErrCh
+		assert.NoError(t, runErr)
+	})
+
+	controlListener, err := (&net.ListenConfig{}).Listen(ctx, "tcp", "127.0.0.1:0")
+	require.NoError(t, err)
+	t.Cleanup(func() {
+		err := controlListener.Close()
+		assert.NoError(t, err, "closing control listener")
+	})
+
+	acceptedConnCh := make(chan net.Conn)
+	go func() {
+		acceptedConn, acceptErr := controlListener.Accept()
+		assert.NoError(t, acceptErr, "accepting control connection")
+		if acceptErr != nil {
+			return
+		}
+		acceptedConnCh <- acceptedConn
+	}()
+
+	clientControlConn, err := (&net.Dialer{}).DialContext(ctx, "tcp", controlListener.Addr().String())
+	require.NoError(t, err)
+	t.Cleanup(func() {
+		err = clientControlConn.Close()
+		assert.NoError(t, err, "closing client control connection")
+	})
+
+	serverControlConn := <-acceptedConnCh
+	t.Cleanup(func() {
+		err := serverControlConn.Close()
+		assert.NoError(t, err, "closing server control connection")
+	})
+
+	association, err := router.registerAssociation(serverControlConn, netip.AddrPort{})
+	require.NoError(t, err)
+	t.Cleanup(func() {
+		router.unregisterAssociation(association)
+	})
+
+	associationCtx, associationCancel := context.WithCancel(ctx)
+	handlerDoneCh := make(chan struct{})
+	go func() {
+		router.runAssociationHandler(associationCtx, association)
+		close(handlerDoneCh)
+	}()
+	t.Cleanup(func() {
+		associationCancel()
+		<-handlerDoneCh
+	})
+
+	udpRouterAddress, err := net.ResolveUDPAddr("udp", router.localAddress().String())
+	require.NoError(t, err)
+
+	clientUDPConn, err := net.DialUDP("udp", nil, udpRouterAddress)
+	require.NoError(t, err)
+	t.Cleanup(func() {
+		err := clientUDPConn.Close()
+		assert.NoError(t, err, "closing client UDP connection")
+	})
+
+	queryID := uint16(rand.Uint32()) //nolint:gosec
+	dnsRequest := &dns.Msg{
+		MsgHdr: dns.MsgHdr{
+			Id:               queryID,
+			RecursionDesired: true,
+		},
+		Question: []dns.Question{{
+			Name:   dns.Fqdn("github.com"),
+			Qtype:  dns.TypeA,
+			Qclass: dns.ClassINET,
+		}},
+	}
+	dnsQuery, err := dnsRequest.Pack()
+	require.NoError(t, err)
+
+	targetAddrPort := netip.MustParseAddrPort("1.1.1.1:53")
+	socksDatagramBuffer := bytes.NewBuffer(nil)
+	err = encodeUDPDatagramToBuffer(socksDatagramBuffer, targetAddrPort, dnsQuery)
+	require.NoError(t, err)
+	socksDatagram := socksDatagramBuffer.Bytes()
+
+	err = clientUDPConn.SetDeadline(deadline)
+	require.NoError(t, err)
+
+	_, err = clientUDPConn.Write(socksDatagram)
+	require.NoError(t, err)
+
+	responseBuffer := make([]byte, maxUDPPacketLength)
+	responseLength, err := clientUDPConn.Read(responseBuffer)
+	require.NoError(t, err)
+
+	responseDestination, responsePayload, err := decodeUDPDatagram(responseBuffer[:responseLength])
+	require.NoError(t, err)
+
+	responseHost, responsePortString, err := net.SplitHostPort(responseDestination)
+	require.NoError(t, err)
+	responsePort, err := strconv.ParseUint(responsePortString, 10, 16)
+	require.NoError(t, err)
+	assert.Equal(t, uint64(53), responsePort)
+	assert.NotEmpty(t, responseHost)
+
+	dnsResponse := new(dns.Msg)
+	err = dnsResponse.Unpack(responsePayload)
+	require.NoError(t, err)
+	assert.Equal(t, queryID, dnsResponse.Id)
+	assert.True(t, dnsResponse.Response)
+	assert.Equal(t, dns.RcodeSuccess, dnsResponse.Rcode)
+	require.NotEmpty(t, dnsResponse.Question)
+	assert.Equal(t, dns.Fqdn("github.com"), dnsResponse.Question[0].Name)
+	assert.Equal(t, dns.TypeA, dnsResponse.Question[0].Qtype)
+	assert.NotEmpty(t, dnsResponse.Answer)
+	require.NoError(t, err)
+}

internal/storage/copy.go

@@ -1,15 +1,23 @@
 package storage
 
 import (
-	"slices"
+	"net/netip"
 
 	"github.com/qdm12/gluetun/internal/models"
 )
 
 func copyServer(server models.Server) (serverCopy models.Server) {
 	serverCopy = server
-	serverCopy.IPs = slices.Clone(server.IPs)
-	serverCopy.PortsTCP = slices.Clone(server.PortsTCP)
-	serverCopy.PortsUDP = slices.Clone(server.PortsUDP)
+	serverCopy.IPs = copyIPs(server.IPs)
 	return serverCopy
 }
+
+func copyIPs(toCopy []netip.Addr) (copied []netip.Addr) {
+	if toCopy == nil {
+		return nil
+	}
+
+	copied = make([]netip.Addr, len(toCopy))
+	copy(copied, toCopy)
+	return copied
+}

internal/storage/copy_test.go

@@ -21,9 +21,43 @@ func Test_copyServer(t *testing.T) {
 	assert.Equal(t, server, serverCopy)
 	// Check for mutation
 	serverCopy.IPs[0] = netip.AddrFrom4([4]byte{9, 9, 9, 9})
-	serverCopy.PortsTCP = []uint16{80}
-	serverCopy.PortsUDP = []uint16{53}
-	assert.NotEqual(t, server.IPs, serverCopy.IPs)
-	assert.NotEqual(t, server.PortsTCP, serverCopy.PortsTCP)
-	assert.NotEqual(t, server.PortsUDP, serverCopy.PortsUDP)
+	assert.NotEqual(t, server, serverCopy)
+}
+
+func Test_copyIPs(t *testing.T) {
+	t.Parallel()
+
+	testCases := map[string]struct {
+		toCopy []netip.Addr
+		copied []netip.Addr
+	}{
+		"nil": {},
+		"empty": {
+			toCopy: []netip.Addr{},
+			copied: []netip.Addr{},
+		},
+		"single IP": {
+			toCopy: []netip.Addr{netip.AddrFrom4([4]byte{1, 1, 1, 1})},
+			copied: []netip.Addr{netip.AddrFrom4([4]byte{1, 1, 1, 1})},
+		},
+		"two IPs": {
+			toCopy: []netip.Addr{netip.AddrFrom4([4]byte{1, 1, 1, 1}), netip.AddrFrom4([4]byte{2, 2, 2, 2})},
+			copied: []netip.Addr{netip.AddrFrom4([4]byte{1, 1, 1, 1}), netip.AddrFrom4([4]byte{2, 2, 2, 2})},
+		},
+	}
+
+	for name, testCase := range testCases {
+		t.Run(name, func(t *testing.T) {
+			t.Parallel()
+
+			copied := copyIPs(testCase.toCopy)
+
+			assert.Equal(t, testCase.copied, copied)
+
+			if len(copied) > 0 {
+				testCase.toCopy[0] = netip.AddrFrom4([4]byte{9, 9, 9, 9})
+				assert.NotEqual(t, testCase.toCopy[0], testCase.copied[0])
+			}
+		})
+	}
 }

internal/storage/filter.go

@@ -3,7 +3,6 @@ package storage
 import (
 	"errors"
 	"fmt"
-	"slices"
 	"strings"
 
 	"github.com/qdm12/gluetun/internal/configuration/settings"
@@ -49,7 +48,6 @@ func (s *Storage) FilterServers(provider string, selection settings.ServerSelect
 	return servers, nil
 }
 
-//nolint:gocognit,gocyclo
 func filterServer(server models.Server,
 	selection settings.ServerSelection,
 ) (filtered bool) {
@@ -92,11 +90,6 @@ func filterServer(server models.Server,
 		return true
 	}
 
-	if (*selection.Dedicated && !server.Dedicated) ||
-		(!*selection.Dedicated && server.Dedicated) {
-		return false
-	}
-
 	if filterByPossibilities(server.Country, selection.Countries) {
 		return true
 	}
@@ -129,14 +122,6 @@ func filterServer(server models.Server,
 		return true
 	}
 
-	serverPorts := server.PortsUDP
-	if server.VPN == vpn.OpenVPN && server.TCP {
-		serverPorts = server.PortsTCP
-	}
-	if filterByPorts(selection, serverPorts) {
-		return true
-	}
-
 	// TODO filter port forward server for PIA
 
 	return false
@@ -180,21 +165,3 @@ func filterByProtocol(selection settings.ServerSelection,
 		return (wantTCP && !serverTCP) || (wantUDP && !serverUDP)
 	}
 }
-
-func filterByPorts(selection settings.ServerSelection,
-	serverPorts []uint16,
-) (filtered bool) {
-	if len(serverPorts) == 0 {
-		return false
-	}
-
-	customPort := *selection.OpenVPN.CustomPort
-	if selection.VPN == vpn.Wireguard {
-		customPort = *selection.Wireguard.EndpointPort
-	}
-	if customPort == 0 {
-		return false
-	}
-
-	return !slices.Contains(serverPorts, customPort)
-}

internal/storage/formatting.go

@@ -14,7 +14,7 @@ func commaJoin(slice []string) string {
 	return strings.Join(slice, ", ")
 }
 
-func noServerFoundError(selection settings.ServerSelection) (err error) { //nolint:gocyclo
+func noServerFoundError(selection settings.ServerSelection) (err error) {
 	var messageParts []string
 
 	messageParts = append(messageParts, "VPN "+selection.VPN)
@@ -155,15 +155,6 @@ func noServerFoundError(selection settings.ServerSelection) (err error) { //noli
 			"target ip address "+targetIP.String())
 	}
 
-	customPort := *selection.OpenVPN.CustomPort
-	if selection.VPN == vpn.Wireguard {
-		customPort = *selection.Wireguard.EndpointPort
-	}
-	if customPort > 0 {
-		messageParts = append(messageParts,
-			fmt.Sprintf("%s endpoint port %d", selection.VPN, customPort))
-	}
-
 	message := "for " + strings.Join(messageParts, "; ")
 
 	return fmt.Errorf("no server found: %s", message)

internal/storage/hardcoded.go

@@ -1,39 +1,26 @@
 package storage
 
 import (
-	"embed"
 	"encoding/json"
 	"fmt"
-	"path"
+	"path/filepath"
 
 	serversmodule "github.com/qdm12/gluetun-servers/pkg/servers"
+	"github.com/qdm12/gluetun/internal/constants/providers"
 	"github.com/qdm12/gluetun/internal/models"
 )
 
-//go:embed servers.json
-var allServersEmbedFS embed.FS
-
 func parseHardcodedServers() (allServers models.AllServers) {
-	f, err := allServersEmbedFS.Open("servers.json")
-	if err != nil {
-		panic(err)
-	}
-	defer f.Close() // no-op
-	decoder := json.NewDecoder(f)
-	err = decoder.Decode(&allServers)
-	if err != nil {
-		panic("decoding servers.json: " + err.Error())
-	}
+	allProviders := providers.All()
 
-	for provider, metadata := range allServers.ProviderToServers {
-		if metadata.Filepath == "" {
-			panic(fmt.Sprintf("embedded manifest file servers.json should have the filepath field set for %s", provider))
-		}
-		filename := path.Base(metadata.Filepath)
+	const version = 1
+	allServers.ProviderToServers = make(map[string]models.Servers, len(allProviders))
+	allServers.Version = version
+	for _, provider := range allProviders {
+		filename := provider + ".json"
 		providerFile, err := serversmodule.Files.Open(filename)
 		if err != nil {
-			const rootURL = "https://github.com/qdm12/gluetun-servers/blob/main/pkg/servers"
-			panic(fmt.Sprintf("reading embedded provider file defined at %s/%s: %s", rootURL, filename, err))
+			panic(fmt.Sprintf("reading embedded provider file %s for %s: %s", filename, provider, err))
 		}
 		defer providerFile.Close() // no-op
 
@@ -48,7 +35,8 @@ func parseHardcodedServers() (allServers models.AllServers) {
 				filename, provider))
 		}
 
-		providerServers.Filepath = metadata.Filepath // inherit filepath from servers.json
+		const serversPath = "/gluetun/servers/"
+		providerServers.Filepath = filepath.Join(serversPath, filename)
 		allServers.ProviderToServers[provider] = providerServers
 	}
 

internal/storage/hardcoded_test.go

@@ -33,10 +33,7 @@ func Test_parseHardcodedServers(t *testing.T) {
 func Test_parseHardcodedServers_filepathsAndEmbeddedProviderFiles(t *testing.T) {
 	t.Parallel()
 
-	var hardcodedServers models.AllServers
-	require.NotPanics(t, func() {
-		hardcodedServers = parseHardcodedServers()
-	})
+	hardcodedServers := parseHardcodedServers()
 
 	allProviders := providers.All()
 	for _, provider := range allProviders {

internal/storage/helpers.go

@@ -3,6 +3,5 @@ package storage
 import "fmt"
 
 func panicOnProviderMissingHardcoded(provider string) {
-	panic(fmt.Sprintf("provider %s not found in hardcoded servers map; "+
-		"did you add the provider key in the embedded servers.json?", provider))
+	panic(fmt.Sprintf("provider %s not found in hardcoded servers map", provider))
 }

internal/storage/read_test.go

@@ -152,8 +152,7 @@ func Test_extractServersFromBytes(t *testing.T) {
 			allProviders[0]: 1,
 			// Missing provider allProviders[1]
 		}
-		expectedPanicValue := fmt.Sprintf("provider %s not found in hardcoded servers map; "+
-			"did you add the provider key in the embedded servers.json?", allProviders[1])
+		expectedPanicValue := fmt.Sprintf("provider %s not found in hardcoded servers map", allProviders[1])
 		assert.PanicsWithValue(t, expectedPanicValue, func() {
 			_, _ = s.extractServersFromBytes(b, hardcodedVersions)
 		})

internal/storage/servers.json

@@ -1,75 +0,0 @@
-{
-  "version": 1,
-  "airvpn": {
-    "filepath": "/gluetun/servers/airvpn.json"
-  },
-  "cyberghost": {
-    "filepath": "/gluetun/servers/cyberghost.json"
-  },
-  "expressvpn": {
-    "filepath": "/gluetun/servers/expressvpn.json"
-  },
-  "fastestvpn": {
-    "filepath": "/gluetun/servers/fastestvpn.json"
-  },
-  "giganews": {
-    "filepath": "/gluetun/servers/giganews.json"
-  },
-  "hidemyass": {
-    "filepath": "/gluetun/servers/hidemyass.json"
-  },
-  "ipvanish": {
-    "filepath": "/gluetun/servers/ipvanish.json"
-  },
-  "ivpn": {
-    "filepath": "/gluetun/servers/ivpn.json"
-  },
-  "mullvad": {
-    "filepath": "/gluetun/servers/mullvad.json"
-  },
-  "nordvpn": {
-    "filepath": "/gluetun/servers/nordvpn.json"
-  },
-  "ovpn": {
-    "filepath": "/gluetun/servers/ovpn.json"
-  },
-  "perfect privacy": {
-    "filepath": "/gluetun/servers/perfect privacy.json"
-  },
-  "privado": {
-    "filepath": "/gluetun/servers/privado.json"
-  },
-  "private internet access": {
-    "filepath": "/gluetun/servers/private internet access.json"
-  },
-  "privatevpn": {
-    "filepath": "/gluetun/servers/privatevpn.json"
-  },
-  "protonvpn": {
-    "filepath": "/gluetun/servers/protonvpn.json"
-  },
-  "purevpn": {
-    "filepath": "/gluetun/servers/purevpn.json"
-  },
-  "slickvpn": {
-    "filepath": "/gluetun/servers/slickvpn.json"
-  },
-  "surfshark": {
-    "filepath": "/gluetun/servers/surfshark.json"
-  },
-  "torguard": {
-    "filepath": "/gluetun/servers/torguard.json"
-  },
-  "vpn unlimited": {
-    "filepath": "/gluetun/servers/vpn unlimited.json"
-  },
-  "vpnsecure": {
-    "filepath": "/gluetun/servers/vpnsecure.json"
-  },
-  "vyprvpn": {
-    "filepath": "/gluetun/servers/vyprvpn.json"
-  },
-  "windscribe": {
-    "filepath": "/gluetun/servers/windscribe.json"
-  }
-}

maintenance.md

@@ -1,19 +1,13 @@
 # Maintenance
 
 - Change `Run` methods to `Start`+`Stop`, returning channels rather than injecting them
-- Go 1.18
-  - gofumpt
-  - Use netip
-- Split servers.json
 - Common slice of Wireguard providers in config settings
 - DNS block lists as LFS and built in image
 - Add HTTP server v3 as json rpc
 - Use `github.com/qdm12/ddns-updater/pkg/publicip`
-- Windows and Darwin development support
 
 ## Features
 
-- Authentication with the control server
 - Get announcement from Github file
 - Support multiple connections in custom ovpn
 - Automate IPv6 detection for OpenVPN