podman-image-trust - Man Page

Manage container registry image trust policy

Synopsis

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

Description

Manages which registries you trust as a source of container images  based on its location. (Not available for remote commands)

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 for an entire registry.  Or it could be defined for a particular repository in that registry. Or it could be defined down to a specific signed image inside of the registry.

For example, the following list includes valid scope values that could be 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 signature (“signedBy”).

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

Options

--help, -h

Print usage statement.

--pubkeysfile=KEY1, -f

A path to an exported public key on the local system. Key paths
 will be 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 type.

--type=value, -t

The trust type for this policy entry.
 Accepted values:
   signedBy (default): Require 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

--raw

Output trust policy file as raw JSON

--json, -j

Output trust as JSON for machine parsing

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

sudo podman image trust show

Display trust policy file

sudo podman image trust show --raw

Display trust as JSON

sudo podman image trust show --json

See Also

containers-policy.json(5)

History

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

Referenced By

podman-image(1).

The man page docker-image-trust(1) is an alias of podman-image-trust(1).