Docker support (#99)

* add Dockerfile

* add basic documentation for docker image

* change cmd to entrypoint in Dockerfile

This is so that you can add args without docker assuming you're trying
to override the command

* Create docker-publish.yml github CI action

This is taken from the marketplace, I didn't write this

* correct docker image tag

* fix checkpoint loading (use carry for add)

* Fix digit typos in README

* revamp docker support

don't use volume, use latest alpine so i won't need to bump it
use multistage static build for minimal size with stripping
correctly save git version details

* tweak workflows

* try making cosign work

* Revert "try making cosign work"

This reverts commit a70723db66.

* fix

* remove root dockerfile

---------

Co-authored-by: cathugger <cathugger@cock.li>
Co-authored-by: dunsany <118174187+dunsany@users.noreply.github.com>

.github/workflows/docker-publish.yml

@@ -0,0 +1,85 @@
+name: Docker
+
+# This workflow uses actions that are not certified by GitHub.
+# They are provided by a third-party and are governed by
+# separate terms of service, privacy policy, and support
+# documentation.
+
+on:
+  push:
+    branches: [ "master" ]
+  pull_request:
+    branches: [ "master" ]
+
+env:
+  # Use docker.io for Docker Hub if empty
+  REGISTRY: ghcr.io
+  # github.repository as <account>/<repo>
+  IMAGE_NAME: ${{ github.repository }}
+
+
+jobs:
+  build:
+
+    runs-on: ubuntu-latest
+    permissions:
+      contents: read
+      packages: write
+      # This is used to complete the identity challenge
+      # with sigstore/fulcio when running outside of PRs.
+      id-token: write
+
+    steps:
+      - name: Checkout repository
+        uses: actions/checkout@v3
+
+      # Install the cosign tool except on PR
+      # https://github.com/sigstore/cosign-installer
+      - name: Install cosign
+        if: github.event_name != 'pull_request'
+        uses: sigstore/cosign-installer@v3
+
+      - name: Setup Docker buildx
+        uses: docker/setup-buildx-action@v2
+
+      # Login against a Docker registry except on PR
+      # https://github.com/docker/login-action
+      - name: Log into registry ${{ env.REGISTRY }}
+        if: github.event_name != 'pull_request'
+        uses: docker/login-action@v2
+        with:
+          registry: ${{ env.REGISTRY }}
+          username: ${{ github.actor }}
+          password: ${{ secrets.GITHUB_TOKEN }}
+
+      # Extract metadata (tags, labels) for Docker
+      # https://github.com/docker/metadata-action
+      - name: Extract Docker metadata
+        id: meta
+        uses: docker/metadata-action@v4
+        with:
+          images: ${{ env.REGISTRY }}/${{ env.IMAGE_NAME }}
+
+      # Build and push Docker image with Buildx (don't push on PR)
+      # https://github.com/docker/build-push-action
+      - name: Build and push Docker image
+        id: build-and-push
+        uses: docker/build-push-action@v4
+        with:
+          file: ./contrib/docker/Dockerfile
+          push: ${{ github.event_name != 'pull_request' }}
+          tags: ${{ steps.meta.outputs.tags }}
+          labels: ${{ steps.meta.outputs.labels }}
+          cache-from: type=gha
+          cache-to: type=gha,mode=max
+
+      # Sign the resulting Docker image digest except on PRs.
+      # This will only write to the public Rekor transparency log when the Docker
+      # repository is public to avoid leaking data.  If you would like to publish
+      # transparency data even for private images, pass --force to cosign below.
+      # https://github.com/sigstore/cosign
+      - name: Sign the published Docker image
+        if: ${{ github.event_name != 'pull_request' }}
+        # This step uses the identity token to provision an ephemeral certificate
+        # against the sigstore community Fulcio instance.
+        run: echo "${{ steps.meta.outputs.tags }}" | xargs -I {} cosign sign --yes {}@${{ steps.build-and-push.outputs.digest }}

README.md

@@ -103,6 +103,15 @@ performance-related tips.
   It appears that onionbalance supports loading usual
   `hs_ed25519_secret_key` key so it should work.
 
+* Is there a docker image?
+
+  Yes, if you do not wish to compile mkp224o yourself, you can use
+  the `ghcr.io/cathugger/mkp224o` image like so:
+
+  ```bash
+  docker run --rm -it -v $PWD:/keys ghcr.io/cathugger/mkp224o:master -d /keys neko
+  ```
+
 ### Acknowledgements & Legal
 
 To the extent possible under law, the author(s) have dedicated all