notation
FIPS 140-3Integration & deliveryNotation is a CLI tool for signing and verifying OCI artifacts with trust policies and plugin-based key management.
Notation is a CLI tool for signing and verifying OCI artifacts with trust policies and plugin-based key management.
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:
This is a vendor-built FIPS-enabled image: its cryptography runs on FIPS 140-3 validated modules configured by the upstream vendor. You can inspect the image metadata:
| Standard | FIPS 140-3 |
| Crypto module | Vendor-configured validated modules |
| Cryptography | Validated modules only |
| Use case | Government, regulated industries, compliance workloads |
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.
This image contains Notation, a CLI tool for signing and verifying OCI artifacts, designed to secure container images
and related artifacts in registries and CI/CD pipelines. The container entrypoint is the notation binary. When run
without arguments or with --help, it prints usage information, and subcommands such as sign and verify provide the
primary functionality.
Notation supports core capabilities like artifact signing, signature verification, trust policy enforcement, and key or certificate management, while integrating with registry plugins for cloud key vaults. Notation works with OCI-compliant registries that support the Referrers API and can be used in Kubernetes admission policies or supply chain workflows. This makes the image a portable way to run Notation inside a container, simplifying artifact signing and verification without installing the CLI directly on the host.
Common subcommands include notation sign <artifact>, notation verify <artifact>, notation cert add, and
notation policy show.
Run the container with docker run to start a Notation CLI instance.
$ docker run --rm -it \
registry.ghost-prod.alphabravo.io/ghost-base/notation:<tag> \
--help
The container entrypoint is notation, which defaults to command-line mode. By default, it runs the CLI to execute
commands like sign and verify.
To persist configuration (e.g., trust policies, keys), mount a volume instead of using --rm. The following example
uses /home/nonroot/.config/notation as the default configuration directory:
$ docker run -it \
-v notation-data:/home/nonroot/.config/notation \
registry.ghost-prod.alphabravo.io/ghost-base/notation:<tag> \
verify <artifact-reference>
This allows you to keep configuration and keys after the container stops. Once running, you can use notation sign to
sign OCI artifacts or notation verify to check signatures in your supply chain.
For more advanced usage, refer to the Notation documentation.
Notation can be added to build pipelines to automatically sign container images before pushing them to a registry. This ensures every artifact has a verifiable signature, giving developers and operators confidence in the integrity of the images they deploy.
Kubernetes clusters can use Notation to verify image signatures at admission time through policy engines like Kyverno or Gatekeeper. This prevents unsigned or tampered images from being scheduled, improving supply chain security in multi-tenant or production environments.
Operators can configure Notation with trust policies that define which certificate authorities or keys are valid. This helps organizations standardize signing practices across teams and enforce consistent trust boundaries.
In addition to container images, Notation can sign and verify other OCI artifacts such as Helm charts or SBOMs. This allows operators to maintain a consistent verification workflow across multiple artifact types used in Kubernetes deployments.
| Feature | Non-hardened Notation | Docker Hardened Notation |
|---|---|---|
| Base image | Alpine or Ubuntu-based | Debian hardened base |
| Security | Standard image with basic utilities | Hardened build with security patches and security metadata |
| Shell access | Shell available | No shell |
| Package manager | apk (Alpine) or apt (Ubuntu) | No package manager |
| User | Runs as root. | Runs as non-root user. |
| Data directory | N/A (CLI tool, no persistent data needed) | N/A (stateless CLI tool) |
| Build process | Pre-compiled binaries | Built from source with verified commit |
| Attack surface | 200+ utilities and tools | Only notation binary and CA certificates |
| Debugging | Shell and standard Unix tools | Use Docker Debug or image mount for troubleshooting |
| SBOM | Not included | Software Bill of Materials included |
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:
To view the image variants and get more information about them, select the Tags tab for this repository, and then select a tag.
To migrate your application to a Ghost hardened image, you must update your Dockerfile. At minimum, you must update the base image in your existing Dockerfile to a Ghost hardened image. This and a few other common changes are listed in the following table of migration notes.
| Item | Migration note |
|---|---|
| Base image | Replace your base images in your Dockerfile with a Ghost hardened image. |
| Package management | Non-dev images, intended for runtime, don't contain package managers. Use package managers only in images with a dev tag. |
| Nonroot user | By default, non-dev images, intended for runtime, run as a nonroot user. Ensure that necessary files and directories are accessible to that user. |
| Multi-stage build | Utilize images with a dev tag for build stages and non-dev images for runtime. For binary executables, use a static image for runtime. |
| TLS certificates | Ghost hardened images contain standard TLS certificates by default. There is no need to install TLS certificates. |
| Ports | 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. |
| Entry point | Ghost hardened images may have different entry points than images such as Docker Official Images. Inspect entry points for Ghost hardened images and update your Dockerfile if necessary. |
| No shell | By default, non-dev images, intended for runtime, don't contain a shell. Use dev images in build stages to run shell commands and then copy artifacts to the runtime stage. |
The following steps outline the general migration process.
Find hardened images for your app.
A hardened image may have several variants. Inspect the image tags and find the image variant that meets your needs.
Update the base image in your Dockerfile.
Update the base image in your application's Dockerfile to the hardened image you found in the previous step. For
framework images, this is typically going to be an image tagged as dev because it has the tools needed to install
packages and dependencies.
For multi-stage Dockerfiles, update the runtime image in your Dockerfile.
To ensure that your final image is as minimal as possible, you should use a multi-stage build. All stages in your
Dockerfile should use a hardened image. While intermediary stages will typically use images tagged as dev, your
final runtime stage should use a non-dev image variant.
Install additional packages
Ghost hardened images contain minimal packages in order to reduce the potential attack surface. You may need to install additional packages in your Dockerfile. To view if a package manager is available for an image variant, select the Tags tab for this repository. To view what packages are already installed in an image variant, select the Tags tab for this repository, and then select a tag.
Only images tagged as dev typically have package managers. You should use a multi-stage Dockerfile to install the
packages. Install the packages in the build stage that uses a dev image. Then, if needed, copy any necessary
artifacts to the runtime stage that uses a non-dev image.
For Alpine-based images, you can use apk to install packages. For Debian-based images, you can use apt-get to
install packages.
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 a nonroot user. Ensure that necessary files and directories are accessible to that user. You may need to copy files to different directories or change permissions so your application running as a nonroot user can access them.
To view the user for an image variant, select the Tags tab for this repository.
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.
To see if a shell is available in an image variant and which one, select the Tags tab for this repository.
Ghost hardened images may have different entry points than images such as Docker Official Images.
To view the Entrypoint or CMD defined for an image variant, select the Tags tab for this repository, select a tag, and then select the Specifications tab.