chore(deps): bump actions/checkout from 5 to 6

Bumps [actions/checkout](https://github.com/actions/checkout) from 5 to 6.
- [Release notes](https://github.com/actions/checkout/releases)
- [Changelog](https://github.com/actions/checkout/blob/main/CHANGELOG.md)
- [Commits](https://github.com/actions/checkout/compare/v5...v6)

---
updated-dependencies:
- dependency-name: actions/checkout
  dependency-version: '6'
  dependency-type: direct:production
  update-type: version-update:semver-major
...

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

.github/dependabot.yml

@@ -0,0 +1,20 @@
+version: 2
+updates:
+  - package-ecosystem: github-actions
+    directory: /
+    schedule:
+      interval: weekly
+    open-pull-requests-limit: 10
+    labels:
+      - dependencies
+      - github-actions
+
+  - package-ecosystem: docker
+    directory: /
+    schedule:
+      interval: weekly
+    open-pull-requests-limit: 10
+    labels:
+      - dependencies
+      - docker
+

.github/workflows/docker-build.yml

@@ -0,0 +1,137 @@
+name: Publish Docker Image
+permissions:
+  actions: read
+  checks: read
+  contents: write
+  deployments: read
+  issues: read
+  discussions: read
+  packages: read
+  pages: read
+  pull-requests: read
+  repository-projects: read
+  security-events: write
+  statuses: read
+
+concurrency:
+  group: docker-release-${{ github.ref }}
+  cancel-in-progress: true
+
+on:
+  pull_request:
+    branches:
+      - main
+  push:
+    branches:
+      - main
+
+env:
+  REGISTRY_IMAGE: registry.dangerous.tech/dangeroustech/zerotierbridge
+
+jobs:
+  Docker_Build:
+    name: Docker Build And Release
+    runs-on: ubuntu-latest
+    steps:
+      - name: Checkout Repository
+        uses: actions/checkout@v6
+
+      - name: Set up QEMU
+        uses: docker/setup-qemu-action@v3
+
+      - name: Set up Docker Buildx
+        uses: docker/setup-buildx-action@v3
+
+      - name: Login to Registry
+        if: github.event_name != 'pull_request'
+        id: login
+        uses: docker/login-action@v3
+        with:
+          registry: registry.dangerous.tech
+          username: ${{ secrets.REGISTRY_USERNAME }}
+          password: ${{ secrets.REGISTRY_PASSWORD }}
+
+      - name: Build
+        id: docker_build
+        uses: docker/build-push-action@v6
+        with:
+          context: .
+          build-args: |
+            VERSION=1.16.0-2
+          push: ${{ github.event_name != 'pull_request' }}
+          platforms: linux/amd64,linux/arm64
+          tags: ${{ env.REGISTRY_IMAGE }}:latest
+          provenance: false
+          sbom: false
+          outputs: type=registry,compression=zstd,compression-level=6,oci-mediatypes=true,force-compression=true
+          cache-from: type=gha
+          cache-to: type=gha,mode=max
+
+
+  MergeRefs:
+    name: Publish Multi-Arch Image And Release
+    if: github.ref == 'refs/heads/main'
+    runs-on: ubuntu-latest
+    needs:
+      - Docker_Build
+    steps:
+      - name: Login to Registry
+        id: login
+        uses: docker/login-action@v3
+        with:
+          registry: registry.dangerous.tech
+          username: ${{ secrets.REGISTRY_USERNAME }}
+          password: ${{ secrets.REGISTRY_PASSWORD }}
+
+      - name: Generate SBOM
+        uses: anchore/sbom-action@v0
+        id: sbom
+        with:
+          image: registry.dangerous.tech/dangeroustech/zerotierbridge:latest
+          registry-username: ${{ secrets.REGISTRY_USERNAME }}
+          registry-password: ${{ secrets.REGISTRY_PASSWORD }}
+          format: spdx-json
+          output-file: ./sbom.spdx.json
+
+      - name: Scan SBOM
+        uses: anchore/scan-action@v7
+        id: scan
+        with:
+          sbom: sbom.spdx.json
+          severity-cutoff: medium
+          fail-build: false
+          only-fixed: true
+
+      - name: upload Anchore scan SARIF report
+        uses: github/codeql-action/upload-sarif@v4
+        with:
+          sarif_file: ${{ steps.scan.outputs.sarif }}
+
+      - name: Checkout Repository
+        uses: actions/checkout@v6
+
+      - name: Changelog
+        uses: TriPSs/conventional-changelog-action@v6
+        id: changelog
+        if: ${{ github.event_name != 'pull_request' }}
+        with:
+          github-token: ${{ secrets.GITHUB_TOKEN }}
+          git-message: "chore 🤖: Release {version}"
+          output-file: CHANGELOG.md
+          tag-prefix: v
+          fallback-version: 1.0.0
+          release-count: 0 # preserve all versions in changelog
+          skip-on-empty: false # otherwise we don't publish fixes
+
+      - name: Create Release
+        uses: softprops/action-gh-release@v2
+        id: release
+        if: ${{ steps.changelog.outputs.skipped == 'false' }}
+        env:
+          GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
+        with:
+          tag_name: ${{ steps.changelog.outputs.tag }}
+          name: ${{ steps.changelog.outputs.tag }}
+          body: ${{ steps.changelog.outputs.clean_changelog }}
+          files: |
+            sbom.spdx.json

.gitignore

@@ -0,0 +1,2 @@
+sbom.spdx.json
+results.sarif

CHANGELOG.md

@@ -0,0 +1,153 @@
+## [1.2.4](https://github.com/dangeroustech/ZeroTierBridge/compare/v1.2.3...v1.2.4) (2025-10-26)
+
+
+
+## [1.2.3](https://github.com/dangeroustech/ZeroTierBridge/compare/v1.2.2...v1.2.3) (2025-10-26)
+
+
+
+## [1.2.2](https://github.com/dangeroustech/ZeroTierBridge/compare/v1.2.1...v1.2.2) (2025-10-26)
+
+
+
+## [1.2.1](https://github.com/dangeroustech/ZeroTierBridge/compare/v1.2.0...v1.2.1) (2025-10-26)
+
+
+
+# [1.2.0](https://github.com/dangeroustech/ZeroTierBridge/compare/v1.1.2...v1.2.0) (2025-10-26)
+
+
+### Bug Fixes
+
+* **workflow:** update artifact naming and handling in docker-build.yml ([96ebbf8](https://github.com/dangeroustech/ZeroTierBridge/commit/96ebbf805d2cb3bb4089a5a0dc70114e3c16cc1b))
+
+
+### Features
+
+* **docker:** add health check to Dockerfile for zerotier-cli ([7d643e3](https://github.com/dangeroustech/ZeroTierBridge/commit/7d643e3ff6c0683d335baae5138ceef475cd37c3))
+
+
+
+## [1.1.2](https://github.com/dangeroustech/ZeroTierBridge/compare/v1.1.1...v1.1.2) (2023-10-18)
+
+
+
+## [1.1.1](https://github.com/dangeroustech/ZeroTierBridge/compare/v1.1.0...v1.1.1) (2023-10-17)
+
+
+### Bug Fixes
+
+* 401 ([bca9ec3](https://github.com/dangeroustech/ZeroTierBridge/commit/bca9ec3df76f9c6ea114e099dd9317c58489d0b2))
+* correct deps ([be55349](https://github.com/dangeroustech/ZeroTierBridge/commit/be55349cefbf291a9ce4233e65a785dad4ec3830))
+* correct multiplatform builds ([593036c](https://github.com/dangeroustech/ZeroTierBridge/commit/593036c8ad8099a3a4e7b1ac9b1dcfbdb8e04a98))
+* push by digest again ([8d55074](https://github.com/dangeroustech/ZeroTierBridge/commit/8d550748cde552ef5552e02770842d4e91f99253))
+* push by digest is breaking things ([2c987a3](https://github.com/dangeroustech/ZeroTierBridge/commit/2c987a3bbe0492aaf22b26e446cb7d96a6c9115d))
+* re-setup buildx ([f8d7326](https://github.com/dangeroustech/ZeroTierBridge/commit/f8d73263fdfd328ad38a77ff381e93bd8bda5750))
+* remove tag to hopefully fix digest pushing ([5cd683c](https://github.com/dangeroustech/ZeroTierBridge/commit/5cd683cb7a83e37eb5b4717309d672f35b256c25))
+* set latest tag ([46ee60c](https://github.com/dangeroustech/ZeroTierBridge/commit/46ee60cbc9091e93f977701a771ba9ce0216e5d1))
+
+
+
+# [1.1.0](https://github.com/dangeroustech/ZeroTierBridge/compare/v1.0.13...v1.1.0) (2023-09-23)
+
+
+### Features
+
+* multi-platform builds ([aab5c07](https://github.com/dangeroustech/ZeroTierBridge/commit/aab5c079dcd559b7c3123aa72d02f7691827083e))
+
+
+
+## [1.0.13](https://github.com/dangeroustech/ZeroTierBridge/compare/v1.0.12...v1.0.13) (2023-09-22)
+
+
+
+## [1.0.12](https://github.com/dangeroustech/ZeroTierBridge/compare/v1.0.11...v1.0.12) (2023-09-22)
+
+
+### Bug Fixes
+
+* correct double message ([6e3c269](https://github.com/dangeroustech/ZeroTierBridge/commit/6e3c2690fc612e42c1d2818cc8d4bdfb9d5e39ba))
+
+
+
+## [1.0.11](https://github.com/dangeroustech/ZeroTierBridge/compare/v1.0.10...v1.0.11) (2023-09-22)
+
+
+### Bug Fixes
+
+* only alert on CVEs that have a fix ([977df48](https://github.com/dangeroustech/ZeroTierBridge/commit/977df48644e0a7112dc25f9f04afa6d84ce87db9))
+* pull correct deb package ([fed1c28](https://github.com/dangeroustech/ZeroTierBridge/commit/fed1c2860230d39aeb80178c79697c1c41fed23d))
+
+
+
+## [1.0.10](https://github.com/dangeroustech/ZeroTierBridge/compare/v1.0.9...v1.0.10) (2023-09-22)
+
+
+### Bug Fixes
+
+* upload sarif file ([89e2953](https://github.com/dangeroustech/ZeroTierBridge/commit/89e29531f070539935a93b6f55d791170ea42e72))
+
+
+
+## [1.0.9](https://github.com/dangeroustech/ZeroTierBridge/compare/v1.0.8...v1.0.9) (2023-09-22)
+
+
+
+## [1.0.8](https://github.com/dangeroustech/ZeroTierBridge/compare/v1.0.7...v1.0.8) (2023-09-22)
+
+
+
+## [1.0.7](https://github.com/dangeroustech/ZeroTierBridge/compare/v1.0.6...v1.0.7) (2023-09-22)
+
+
+
+## [1.0.6](https://github.com/dangeroustech/ZeroTierBridge/compare/v0.0.1...v1.0.6) (2023-09-22)
+
+
+
+## [1.0.5](https://github.com/dangeroustech/ZeroTierBridge/compare/v1.0.4...v1.0.5) (2023-09-22)
+
+
+
+## [1.0.4](https://github.com/dangeroustech/ZeroTierBridge/compare/v1.0.3...v1.0.4) (2023-09-22)
+
+
+
+## [1.0.3](https://github.com/dangeroustech/ZeroTierBridge/compare/v1.0.2...v1.0.3) (2023-09-22)
+
+
+
+## [1.0.2](https://github.com/dangeroustech/ZeroTierBridge/compare/v1.0.1...v1.0.2) (2023-09-22)
+
+
+### Bug Fixes
+
+* quick filter to not release on PRs ([c34324b](https://github.com/dangeroustech/ZeroTierBridge/commit/c34324b998690edeadd3d680987587c0fe93c525))
+
+
+
+## [1.0.1](https://github.com/dangeroustech/ZeroTierBridge/compare/v1.0.0...v1.0.1) (2023-09-22)
+
+
+
+# [1.0.0](https://github.com/dangeroustech/ZeroTierBridge/compare/f902dcc0c4615801fb65e6c90342efe96789319f...v1.0.0) (2023-09-22)
+
+
+### Bug Fixes
+
+* add openssl dep and remove pinning ([1298cea](https://github.com/dangeroustech/ZeroTierBridge/commit/1298cea4fa1bad3141754e5218f449ec15e8469a))
+* allow bi-directional traffic initiation ([90cf5b1](https://github.com/dangeroustech/ZeroTierBridge/commit/90cf5b1684b6221797b39af306c3fee9ce5bdb9e))
+* ci: lowercase tag names ([fc24b78](https://github.com/dangeroustech/ZeroTierBridge/commit/fc24b78d4a1046ebc2b01560ed4b67e33418c30e))
+* ci: use correct registry ([3b29bee](https://github.com/dangeroustech/ZeroTierBridge/commit/3b29bee4c642cf04c3af89a7c16f004531f83622))
+* ci: use full registry name ([3a5eb50](https://github.com/dangeroustech/ZeroTierBridge/commit/3a5eb50b13cf7cab7939c4b49c14093189aae330))
+* set proper workdir ([7f56fec](https://github.com/dangeroustech/ZeroTierBridge/commit/7f56fec6897635e37b3e5aa13e7c3bbfddbce5da))
+* standardise network env again ([3e65156](https://github.com/dangeroustech/ZeroTierBridge/commit/3e65156a3c955fa6c6715a7d9e15a799c6f3f735))
+
+
+### Features
+
+* add docker-compose.yml ([f902dcc](https://github.com/dangeroustech/ZeroTierBridge/commit/f902dcc0c4615801fb65e6c90342efe96789319f))
+* support multiple zt network joins ([556195c](https://github.com/dangeroustech/ZeroTierBridge/commit/556195cd64f33fbbc9244022c8a99af5284ffbb9))
+
+
+

Dockerfile

@@ -1,17 +1,41 @@
-FROM debian:buster as stage
-ARG PACKAGE_BASEURL=https://download.zerotier.com/debian/buster/pool/main/z/zerotier-one
-ARG ARCH=amd64
-ARG VERSION=1.6.5
-RUN apt-get update -qq && apt-get install -qq --no-install-recommends -y ca-certificates=20200601~deb10u2 curl=7.64.0-4+deb10u2
-RUN curl -sSL -o zerotier-one.deb "${PACKAGE_BASEURL}/zerotier-one_${VERSION}_${ARCH}.deb"
+FROM debian:13.1 AS stage
+SHELL ["/bin/bash", "-o", "pipefail", "-c"]
+ENV DEBIAN_FRONTEND=noninteractive
+ARG PACKAGE_BASEURL=https://download.zerotier.com/debian/trixie/pool/main/z/zerotier-one
+ARG TARGETARCH
+ARG VERSION=1.16.0-2
+RUN apt-get update -qq && apt-get install -qq --no-install-recommends -y \
+    ca-certificates=20250419 \
+    curl=8.14.1-2
+RUN set -e; \
+    DETECTED_ARCH="${TARGETARCH:-}"; \
+    if [ -z "$DETECTED_ARCH" ]; then DETECTED_ARCH="$(dpkg --print-architecture)"; fi; \
+    case "$DETECTED_ARCH" in \
+      amd64|x86_64) ARCH_MAPPING=amd64 ;; \
+      arm64|aarch64) ARCH_MAPPING=arm64 ;; \
+      armhf|armv7*) ARCH_MAPPING=armhf ;; \
+      *) echo "Unsupported architecture: $DETECTED_ARCH" >&2; exit 1 ;; \
+    esac; \
+    echo "Downloading ZeroTier: arch=$ARCH_MAPPING version=$VERSION"; \
+    curl -fsSL -o zerotier-one.deb "${PACKAGE_BASEURL}/zerotier-one_${VERSION}_${ARCH_MAPPING}.deb"
 
-FROM debian:buster
+FROM debian:13.1
+SHELL ["/bin/bash", "-o", "pipefail", "-c"]
+ENV DEBIAN_FRONTEND=noninteractive
+ARG VERSION
+RUN mkdir /app
+WORKDIR /app
 COPY --from=stage zerotier-one.deb .
-RUN apt-get update -qq && apt-get install -qq --no-install-recommends -y procps=2:3.3.15-2 iptables=1.8.2-4 \
+RUN apt-get update -qq && apt-get install -qq --no-install-recommends -y \
+    adduser=3.152 \
+    procps=2:4.0.4-9 \
+    iptables=1.8.11-2 \
+    openssl=3.5.1-1 \
     && apt-get clean \
     && rm -rf /var/lib/apt/lists/*
 RUN dpkg -i zerotier-one.deb && rm -f zerotier-one.deb
 RUN echo "${VERSION}" >/etc/zerotier-version
-COPY entrypoint.sh /entrypoint.sh
-RUN chmod 755 /entrypoint.sh
-ENTRYPOINT ["/entrypoint.sh"]
+COPY entrypoint.sh entrypoint.sh
+RUN chmod 755 entrypoint.sh
+HEALTHCHECK --interval=30s --timeout=5s --start-period=60s --retries=3 CMD sh -c 'zerotier-cli info 2>/dev/null | grep -q ONLINE'
+ENTRYPOINT ["/app/entrypoint.sh"]

README.md

@@ -4,9 +4,11 @@ A container to provide out-of-the-box bridging functionality to a ZeroTier netwo
 
 ## Running
 
-`docker build -t zerotierbridge .`
+### Prerequisites
 
-`docker run --privileged -e ZT_NETWORK=NETWORK_ID_HERE zerotierbridge:latest`
+- Docker running as your logged in user (if `docker ps` runs then you're good, if not follow the link ->) - [Linux instructions here](https://docs.docker.com/engine/install/linux-postinstall/)
+
+### ZeroTier UI Changes
 
 Once running, log into your ZeroTier interface and approve the new device. Click the wrench next to the name and select 'Allow Ethernet Bridging.'
 
@@ -16,13 +18,30 @@ You also need to add a static route into ZeroTier so that the traffic is routed
 
 ![brave_4wHd9zo193](https://user-images.githubusercontent.com/1135584/129230132-11bcfb72-7d9b-4b40-a4e5-72130c583077.png)
 
-### Caveat: Architecture
+### Docker Compose
 
-If you need to run this on a device with different architecture (a raspberry pi, for instance), then just edit line 3 of the Dockerfile.
+Edit the `ZT_NETWORKS` variable in `docker-compose.yml` to add your networks. Multi-arch images are published automatically; no architecture changes are needed.
 
-If you were using a Raspberry Pi 4, you would change this to `ARCH=arm64` and the container will pull the correct ZeroTier installer.
+Easiest way to bring up is via Docker Compose. Rename `docker-compose.yml.example` to `docker-compose.yml` and run `docker compose up -d`.
 
-## TODO
+If you want to disable bridging, set `ZT_BRIDGE=false`. This can be done after the initial networks have been joined (just change the environment variable in the `docker-compose.yml` file and restart), as the ZeroTier config persists but IPTables forwarding is done on each container startup.
 
-- Add docker-compose.yml
-- Add kubernetes deployment YAML
+### OG Docker
+
+`docker build -t zerotierbridge .`
+
+`docker run --cap-add NET_ADMIN --cap-add NET_RAW --sysctl net.ipv4.ip_forward=1 -e ZT_NETWORKS="NETWORK_1 NETWORK_2" -e ZT_BRIDGE=true zerotierbridge:latest`
+
+Add your network ID(s) into the `ZT_NETWORKS` argument, space separated.
+
+Disable bridging by passing `ZT_BRIDGE=false`. This can be done after the initial networks have been joined (just restart the container), as the ZeroTier config persists but IPTables forwarding is done on each container startup.
+
+#### Persistent Storage
+
+If you would like the container to retain the same ZeroTier client ID on reboot, attach a volume as per the below.
+
+`docker run --privileged -e ZT_NETWORKS=NETWORK_ID_HERE ZT_BRIDGE=true -v zt_config:/var/lib/zerotier-one/ zerotierbridge:latest`
+
+#### Notes
+
+If your host requires additional privileges for networking, you may need to add device and capabilities in your runtime configuration. The provided Docker Compose example includes `cap_add: [NET_ADMIN, NET_RAW]` and `sysctls` for IP forwarding.

docker-compose.yml.example

@@ -0,0 +1,19 @@
+version: "3"
+
+services:
+  zerotierbridge:
+    container_name: zerotierbridge
+    image: registry.dangerous.tech/dangeroustech/zerotierbridge
+    restart: always
+    cap_add:
+      - NET_ADMIN
+      - NET_RAW
+    sysctls:
+      net.ipv4.ip_forward: "1"
+    volumes:
+      - zt_config:/var/lib/zerotier-one
+    environment:
+      ZT_NETWORKS: "NETWORK_ID_1 NETWORK_ID_2 NETWORK_ID_3"
+      ZT_BRIDGE: "true"
+volumes:
+  zt_config:

entrypoint.sh

@@ -1,40 +1,57 @@
 #!/bin/sh
 
-grepzt() {
-  (find /proc -name exe | xargs -I{} readlink {}) 2>/dev/null | grep -q zerotier-one
-  return $?
+set -eu
+
+terminate() {
+  # Try to terminate zerotier-one gracefully
+  if [ -n "${ZT_PID:-}" ]; then
+    kill -TERM "$ZT_PID" 2>/dev/null || true
+    wait "$ZT_PID" 2>/dev/null || true
+  fi
 }
+trap terminate INT TERM
 
 echo "starting zerotier"
 setsid /usr/sbin/zerotier-one &
+ZT_PID=$!
 
-while ! grepzt
-do
+# Wait for zerotier to be responsive
+until zerotier-cli info >/dev/null 2>&1; do
   echo "zerotier hasn't started, waiting a second"
   sleep 1
 done
 
-echo "joining networks: $ZT_NETWORK"
+# Set IPTables to allow NATting
+sysctl -w net.ipv4.ip_forward=1 > /dev/null
 
-echo "joining $ZT_NETWORK"
+echo "joining networks: ${ZT_NETWORKS:-}"
 
-while ! zerotier-cli join "$ZT_NETWORK"
-do 
-    echo "joining $ZT_NETWORK failed; trying again in 1s"
+for n in ${ZT_NETWORKS:-}; do
+  echo "joining $n"
+
+  until zerotier-cli join "$n"; do
+    echo "joining $n failed; trying again in 1s"
     sleep 1
   done
 
+  if [ "${ZT_BRIDGE:-true}" = "true" ]; then
+    ZT_IFACE=$(zerotier-cli get "$n" portDeviceName)
+    PHY_IFACE=eth0
+    echo "Configuring iptables on ${ZT_IFACE}"
 
-### Set IPTables to allow NATting
-echo "setting up NATting"
-sysctl -w net.ipv4.ip_forward=1
-PHY_IFACE=eth0; ZT_IFACE=$(ls /sys/class/net | grep ^zt)
+    # idempotent rules
+    iptables -t nat -C POSTROUTING -o "$PHY_IFACE" -j MASQUERADE 2>/dev/null || iptables -t nat -A POSTROUTING -o "$PHY_IFACE" -j MASQUERADE
+    iptables -t nat -C POSTROUTING -o "$ZT_IFACE" -j MASQUERADE 2>/dev/null || iptables -t nat -A POSTROUTING -o "$ZT_IFACE" -j MASQUERADE
+    iptables -C FORWARD -i "$PHY_IFACE" -o "$ZT_IFACE" -j ACCEPT 2>/dev/null || iptables -A FORWARD -i "$PHY_IFACE" -o "$ZT_IFACE" -j ACCEPT
+    iptables -C FORWARD -i "$ZT_IFACE" -o "$PHY_IFACE" -j ACCEPT 2>/dev/null || iptables -A FORWARD -i "$ZT_IFACE" -o "$PHY_IFACE" -j ACCEPT
+  fi
+done
 
-iptables -t nat -A POSTROUTING -o $PHY_IFACE -j MASQUERADE
-iptables -A FORWARD -i $PHY_IFACE -o $ZT_IFACE -m state --state RELATED,ESTABLISHED -j ACCEPT
-iptables -A FORWARD -i $ZT_IFACE -o $PHY_IFACE -j ACCEPT
+# Give ZT a second to realise it's online
+sleep 10
 
-echo "iptables --list-rules"
-echo "$(ip a)"
+# Print Client Info
+zerotier-cli info || true
 
-sleep infinity
+# Keep the container running while zerotier-one is alive
+wait "$ZT_PID"

package.json

@@ -0,0 +1,3 @@
+{
+  "version": "1.2.4"
+}