open policy agent
SecurityOPA is a policy engine that streamlines policy management across your stack for improved development, security and audit capability.
OPA is a policy engine that streamlines policy management across your stack for improved development, security and audit capability.
Pull the latest version of this image from the Ghost registry. Pulling requires authentication — generate a token and run docker login first (see Authentication below).
The Ghost catalog is public to browse, but pulling images requires an account. Generate a pull token below (or from your Account → Tokens page) — you'll get a ready-to-paste docker login command, then docker pull works.
The username is generated automatically (it looks like robot$<project>+<auto-id>, not the name you typed) and is included in the docker login command above. The secret is shown only once when you create the token.
All Ghost images are signed with cosign. Verifying the signature before deployment ensures the image has not been tampered with.
Install cosign via brew install cosign or download from the Sigstore releases page.
Reference this image in your Dockerfile as a base layer:
All examples in this guide use the public image. If you’ve mirrored the repository for your own use (for example, to your Docker Hub namespace), update your commands to reference the mirrored image instead of the public one.
For example:
registry.ghost-prod.alphabravo.io/ghost-base/<repository>:<tag><your-namespace>/dhi-<repository>:<tag>For the examples, you must first use docker login registry.ghost-prod.alphabravo.io to authenticate to the registry to pull the images.
Refer to the upstream's documentation on the subject of running opa.
Ghost hardened images come in different variants depending on their intended use. Image variants are identified by their tag.
Runtime variants are designed to run your application in production. These images are intended to be used either
directly or as the FROM image in the final stage of a multi-stage build. These images typically:
Build-time variants typically include dev in the tag name and are intended for use in the first stage of a
multi-stage Dockerfile. These images typically:
FIPS variants include fips in the variant name and tag. They come in both runtime and build-time variants. These
variants use cryptographic modules that have been validated under FIPS 140, a U.S. government standard for secure
cryptographic operations. For example, usage of MD5 fails in FIPS variants.
To view the image variants and get more information about them, select the Tags tab for this repository, and then select a tag.
Run the following command to run an open policy agent container. Replace <tag> with the image variant you want to run.
$ docker run registry.ghost-prod.alphabravo.io/ghost-base/open-policy-agent:<tag>
The following are common issues that you may encounter during migration.
The hardened images intended for runtime don't contain a shell nor any tools for debugging. The recommended method for debugging applications built with Ghost hardened images is to use Docker Debug to attach to these containers. Docker Debug provides a shell, common debugging tools, and lets you install other tools in an ephemeral, writable layer that only exists during the debugging session.
By default image variants intended for runtime, run as the nonroot user. Ensure that necessary files and directories are accessible to the nonroot user. You may need to copy files to different directories or change permissions so your application running as the nonroot user can access them.
Non-dev hardened images run as a nonroot user by default. As a result, applications in these images can't bind to
privileged ports (below 1024) when running in Kubernetes or in Docker Engine versions older than 20.10. To avoid issues,
configure your application to listen on port 1025 or higher inside the container, even if you map it to a lower port on
the host. For example, docker run -p 80:8080 my-image will work because the port inside the container is 8080, and
docker run -p 80:81 my-image won't work because the port inside the container is 81.
By default, image variants intended for runtime don't contain a shell. Use dev images in build stages to run shell
commands and then copy any necessary artifacts into the runtime stage. In addition, use Docker Debug to debug containers
with no shell.
Ghost hardened images may have different entry points than images such as Docker Official Images. Use docker inspect
to inspect entry points for Ghost hardened images and update your Dockerfile if necessary.