podman-image-trust(1)

NAME
podman-image-trust - Manage container registry image trust policy

SYNOPSIS
podman image trust set|show [options] registry[/repository]

DESCRIPTION
Manages which registries to trust as a source of container images based on its location. (This option is not available with the remote Podman client, including Mac and Windows (excluding WSL2) machines)

The location is determined by the transport and the registry host of the image. Using this container image docker://docker.io/library/busybox as an example, docker is the transport and docker.io is the registry host.

Trust is defined in /etc/containers/policy.json and is enforced when a user attempts to pull a remote image from a registry. The trust policy in policy.json describes a registry scope (registry and/or repository) for the trust. This trust can use public keys for signed images.

The scope of the trust is evaluated from most specific to the least specific. In other words, a policy may be:

•   Defined to an entire registry.

•   Defined to a particular repository in that registry.

•   Defined to a specific signed image inside of the registry.

The following list are examples of valid scope values used in policy.json from most specific to the least specific:

docker.io/library/busybox:notlatest

docker.io/library/busybox

docker.io/library

docker.io

If no configuration is found for any of these scopes, the default value (specified by using "default" instead of REGISTRY[/REPOSITORY]) is used.

Trust type provides a way to:

Allowlist ("accept") or Denylist ("reject") registries or Require a simple signing signature (“signedBy”), Require a sigstore signature ("sigstoreSigned").

Trust may be updated using the command podman image trust set for an existing trust scope.

OPTIONS

  --help, -h
Print usage statement.

  set OPTIONS

  --pubkeysfile, -f=KEY1
A path to an exported public key on the local system. Key paths
  are referenced in policy.json. Any path to a file may be used but locating the file in /etc/pki/containers is recommended. Options may be used multiple times to
  require an image be signed by multiple keys. The --pubkeysfile option is required for the signedBy and sigstoreSigned types.

  --type, -t=value
The trust type for this policy entry.
  Accepted values:
    signedBy (default): Require simple signing signatures with corresponding list of
                        public keys
    sigstoreSigned: Require sigstore signatures with corresponding list of
                        public keys
    accept: do not require any signatures for this
            registry scope
    reject: do not accept images for this registry scope

  show OPTIONS

  --json, -j
Output trust as JSON for machine parsing

  --noheading, -n
Omit the table headings from the listing.

  --raw
Output trust policy file as raw JSON

EXAMPLES
Accept all unsigned images from a registry:
    sudo podman image trust set --type accept docker.io

Modify default trust policy:
    sudo podman image trust set -t reject default

Display system trust policy:
    podman image trust show
    TRANSPORT      NAME                        TYPE        ID                   STORE
    all            default                     reject
    repository     docker.io/library           accept
    repository     registry.access.redhat.com  signed      security@redhat.com  https://access.redhat.com/webassets/docker/content/sigstore
    repository     registry.redhat.io          signed      security@redhat.com  https://registry.redhat.io/containers/sigstore
    repository     docker.io                   reject
    docker-daemon                              accept

Display trust policy file:
    podman image trust show --raw
    {
        "default": [
            {
                "type": "reject"
            }
        ],
        "transports": {
            "docker": {
                "docker.io": [
                    {
                        "type": "reject"
                    }
                ],
                "docker.io/library": [
                    {
                        "type": "insecureAcceptAnything"
                    }
                ],
                "registry.access.redhat.com": [
                    {
                        "type": "signedBy",
                        "keyType": "GPGKeys",
                        "keyPath": "/etc/pki/rpm-gpg/RPM-GPG-KEY-redhat-release"
                    }
                ],
                "registry.redhat.io": [
                    {
                        "type": "signedBy",
                        "keyType": "GPGKeys",
                        "keyPath": "/etc/pki/rpm-gpg/RPM-GPG-KEY-redhat-release"
                    }
                ]
            },
            "docker-daemon": {
                "": [
                    {
                        "type": "insecureAcceptAnything"
                    }
                ]
            }
        }
    }

Display trust as JSON:
    podman image trust show --json
    [
      {
        "transport": "all",
        "name": "* (default)",
        "repo_name": "default",
        "type": "reject"
      },
      {
        "transport": "repository",
        "name": "docker.io",
        "repo_name": "docker.io",
        "type": "reject"
      },
      {
        "transport": "repository",
        "name": "docker.io/library",
        "repo_name": "docker.io/library",
        "type": "accept"
      },
      {
        "transport": "repository",
        "name": "registry.access.redhat.com",
        "repo_name": "registry.access.redhat.com",
        "sigstore": "https://access.redhat.com/webassets/docker/content/sigstore",
        "type": "signed",
        "gpg_id": "security@redhat.com"
      },
      {
        "transport": "repository",
        "name": "registry.redhat.io",
        "repo_name": "registry.redhat.io",
        "sigstore": "https://registry.redhat.io/containers/sigstore",
        "type": "signed",
        "gpg_id": "security@redhat.com"
      },
      {
        "transport": "docker-daemon",
        "type": "accept"
      }
    ]

SEE ALSO
containers-policy.json(5) ⟨https://github.com/containers/image/blob/main/docs/containers-policy.json.5.md⟩

HISTORY
January 2019, updated by Tom Sweeney (tsweeney at redhat dot com) December 2018, originally compiled by Qi Wang (qiwan at redhat dot com)