docker trust sign

Estimated reading time: 3 minutes

Description

Sign an image

Usage

docker trust sign IMAGE:TAG

Options

Name, shorthand	Default	Description
`--local`		Sign a locally tagged image

Parent command

Command	Description
docker trust	Manage trust on Docker images

Command	Description
docker trust inspect	Return low-level information about keys and signatures
docker trust key	Manage keys for signing Docker images
docker trust revoke	Remove trust for an image
docker trust sign	Sign an image
docker trust signer	Manage entities who can sign Docker images

Extended description

docker trust sign adds signatures to tags to create signed repositories.

Examples

Sign a tag as a repo admin

Given an image:

$ docker trust view example/trust-demo
SIGNED TAG          DIGEST                                                             SIGNERS
v1                  c24134c079c35e698060beabe110bb83ab285d0d978de7d92fed2c8c83570a41   (Repo Admin)

Administrative keys for example/trust-demo:
Repository Key:	36d4c3601102fa7c5712a343c03b94469e5835fb27c191b529c06fd19c14a942
Root Key:	246d360f7c53a9021ee7d4259e3c5692f3f1f7ad4737b1ea8c7b8da741ad980b

Sign a new tag with docker trust sign:

$ docker trust sign example/trust-demo:v2
Signing and pushing trust metadata for example/trust-demo:v2
The push refers to a repository [docker.io/example/trust-demo]
eed4e566104a: Layer already exists
77edfb6d1e3c: Layer already exists
c69f806905c2: Layer already exists
582f327616f1: Layer already exists
a3fbb648f0bd: Layer already exists
5eac2de68a97: Layer already exists
8d4d1ab5ff74: Layer already exists
v2: digest: sha256:8f6f460abf0436922df7eb06d28b3cdf733d2cac1a185456c26debbff0839c56 size: 1787
Signing and pushing trust metadata
Enter passphrase for repository key with ID 36d4c36:
Successfully signed docker.io/example/trust-demo:v2

docker trust view lists the new signature:

$ docker trust view example/trust-demo
SIGNED TAG          DIGEST                                                             SIGNERS
v1                  c24134c079c35e698060beabe110bb83ab285d0d978de7d92fed2c8c83570a41   (Repo Admin)
v2                  8f6f460abf0436922df7eb06d28b3cdf733d2cac1a185456c26debbff0839c56   (Repo Admin)

Administrative keys for example/trust-demo:
Repository Key:	36d4c3601102fa7c5712a343c03b94469e5835fb27c191b529c06fd19c14a942
Root Key:	246d360f7c53a9021ee7d4259e3c5692f3f1f7ad4737b1ea8c7b8da741ad980b

Sign a tag as a signer