[FEATURE] Add OpenVPN

Author: IanSun

.github/workflows/openvpn.yaml

@@ -0,0 +1,51 @@
+name: OpenVPN
+
+on:
+  push:
+    paths:
+    - openvpn/**
+  schedule:
+  - cron: 0 0 * * *
+  workflow_dispatch:
+
+jobs:
+  update:
+    runs-on: ubuntu-latest
+    outputs:
+      version: ${{ steps.version.outputs.version }}
+    steps:
+    - uses: docker/login-action@v1
+      with:
+        username: ${{ secrets.DOCKERHUB_USERNAME }}
+        password: ${{ secrets.DOCKERHUB_TOKEN }}
+    - id: version
+      env:
+        DOCKER_CLI_EXPERIMENTAL: enabled
+      run: |
+        export VERSION=$(curl https://dl-cdn.alpinelinux.org/alpine/edge/main/x86_64/APKINDEX.tar.gz | tar -Oxz | grep -FaxA1 "P:openvpn" | tail -n1 | cut -d: -f2)
+        docker manifest inspect ${{ secrets.DOCKERHUB_USERNAME }}/openvpn:${VERSION} > /dev/null && echo "" || echo "::set-output name=version::${VERSION}"
+  publish:
+    needs: update
+    if: ${{ needs.update.outputs.version }}
+    runs-on: ubuntu-latest
+    steps:
+    - uses: actions/checkout@v2
+    - uses: docker/setup-qemu-action@v1
+    - uses: docker/setup-buildx-action@v1
+    - uses: docker/login-action@v1
+      with:
+        username: ${{ secrets.DOCKERHUB_USERNAME }}
+        password: ${{ secrets.DOCKERHUB_TOKEN }}
+    - uses: docker/build-push-action@v2
+      with:
+        build-args: |
+          VERSION=${{ needs.update.outputs.version }}
+        context: openvpn
+        file: openvpn/Dockerfile
+        platforms: |
+          linux/amd64
+          linux/arm64
+        push: true
+        tags: |
+          ${{ secrets.DOCKERHUB_USERNAME }}/openvpn
+          ${{ secrets.DOCKERHUB_USERNAME }}/openvpn:${{ needs.update.outputs.version }}

openvpn/Dockerfile

@@ -0,0 +1,19 @@
+FROM alpine:edge
+
+ARG VERSION
+
+COPY rootfs/ /
+
+RUN set -ex; \
+  apk add --no-cache \
+    iptables \
+    ip6tables \
+    openvpn="${VERSION}" \
+  ;
+
+EXPOSE 1194
+EXPOSE 1194/udp
+
+VOLUME [ "/etc/openvpn" ]
+
+ENTRYPOINT [ "/sbin/init" ]

openvpn/rootfs/sbin/init

@@ -0,0 +1,8 @@
+#!/bin/sh
+
+if [ ! -c "/dev/net/tun" ]; then
+  mkdir -p "/dev/net"
+  mknod "/dev/net/tun" c 10 200
+fi
+
+exec $@