cli/registry/client: set actions when authn with token

When using a personal access token, Docker Hub produces an error if actions
are requested beyond the token's allowed actions. This resulted in errors
when using a PAT with limited permissions to do a "docker manifest inspect".

This patch sets actions to "pull" only by default, and requests "push" action
for requests that need it.

To verify:

- create a PAT with limited access (read-only)
- log in with your username and the PAT as password

Before this patch:

    docker manifest inspect ubuntu:latest
    Get "https://registry-1.docker.io/v2/library/ubuntu/manifests/latest": unauthorized: access token has insufficient scopes

With this patch applied:

    docker manifest inspect ubuntu:latest
    {
       "schemaVersion": 2,
       "mediaType": "application/vnd.oci.image.index.v1+json",
       "manifests": [
          {
             "mediaType": "application/vnd.oci.image.manifest.v1+json",
             "size": 424,
             "digest": "sha256:56887c5194fddd8db7e36ced1c16b3569d89f74c801dc8a5adbf48236fb34564",
             "platform": {
                "architecture": "amd64",
                "os": "linux"
             }
          },
          {
             "mediaType": "application/vnd.oci.image.manifest.v1+json",
             "size": 424,
             "digest": "sha256:c835a4f2a632bc91a2b494e871549f0dd83f2966c780e66435774e77e048ddf0",
             "platform": {
                "architecture": "arm",
                "os": "linux",
                "variant": "v7"
             }
          }
       ]
    }

Signed-off-by: Sebastiaan van Stijn <github@gone.nl>

Author: thaJeztah

cli/registry/client/client.go

@@ -7,6 +7,7 @@ import (
 	"strings"
 
 	manifesttypes "github.com/docker/cli/cli/manifest/types"
+	"github.com/docker/cli/cli/trust"
 	"github.com/docker/distribution"
 	"github.com/docker/distribution/reference"
 	distributionclient "github.com/docker/distribution/registry/client"
@@ -77,6 +78,7 @@ func (c *client) MountBlob(ctx context.Context, sourceRef reference.Canonical, t
 	if err != nil {
 		return err
 	}
+	repoEndpoint.actions = trust.ActionsPushAndPull
 	repo, err := c.getRepositoryForReference(ctx, targetRef, repoEndpoint)
 	if err != nil {
 		return err
@@ -102,6 +104,7 @@ func (c *client) PutManifest(ctx context.Context, ref reference.Named, manifest
 		return digest.Digest(""), err
 	}
 
+	repoEndpoint.actions = trust.ActionsPushAndPull
 	repo, err := c.getRepositoryForReference(ctx, ref, repoEndpoint)
 	if err != nil {
 		return digest.Digest(""), err
@@ -151,7 +154,9 @@ func (c *client) getHTTPTransportForRepoEndpoint(ctx context.Context, repoEndpoi
 		c.authConfigResolver(ctx, repoEndpoint.info.Index),
 		repoEndpoint.endpoint,
 		repoEndpoint.Name(),
-		c.userAgent)
+		c.userAgent,
+		repoEndpoint.actions,
+	)
 	return httpTransport, errors.Wrap(err, "failed to configure transport")
 }
 

cli/registry/client/endpoint.go

@@ -6,6 +6,7 @@ import (
 	"net/http"
 	"time"
 
+	"github.com/docker/cli/cli/trust"
 	"github.com/docker/distribution/reference"
 	"github.com/docker/distribution/registry/client/auth"
 	"github.com/docker/distribution/registry/client/transport"
@@ -17,6 +18,7 @@ import (
 type repositoryEndpoint struct {
 	info     *registry.RepositoryInfo
 	endpoint registry.APIEndpoint
+	actions  []string
 }
 
 // Name returns the repository name
@@ -74,7 +76,7 @@ func getDefaultEndpointFromRepoInfo(repoInfo *registry.RepositoryInfo) (registry
 }
 
 // getHTTPTransport builds a transport for use in communicating with a registry
-func getHTTPTransport(authConfig registrytypes.AuthConfig, endpoint registry.APIEndpoint, repoName string, userAgent string) (http.RoundTripper, error) {
+func getHTTPTransport(authConfig registrytypes.AuthConfig, endpoint registry.APIEndpoint, repoName, userAgent string, actions []string) (http.RoundTripper, error) {
 	// get the http transport, this will be used in a client to upload manifest
 	base := &http.Transport{
 		Proxy: http.ProxyFromEnvironment,
@@ -98,8 +100,11 @@ func getHTTPTransport(authConfig registrytypes.AuthConfig, endpoint registry.API
 		passThruTokenHandler := &existingTokenHandler{token: authConfig.RegistryToken}
 		modifiers = append(modifiers, auth.NewAuthorizer(challengeManager, passThruTokenHandler))
 	} else {
+		if len(actions) == 0 {
+			actions = trust.ActionsPullOnly
+		}
 		creds := registry.NewStaticCredentialStore(&authConfig)
-		tokenHandler := auth.NewTokenHandler(authTransport, creds, repoName, "push", "pull")
+		tokenHandler := auth.NewTokenHandler(authTransport, creds, repoName, actions...)
 		basicHandler := auth.NewBasicHandler(creds)
 		modifiers = append(modifiers, auth.NewAuthorizer(challengeManager, tokenHandler, basicHandler))
 	}