auto-update: validate container image

Auto updates using the "registry" policy require container to be created
with a fully-qualified image reference.  Short names are not supported
due the ambiguity of their source registry.  Initially, container
creation errored out for non FQN images but it seems that Podman has
regressed.

Fixes: containers#15879
Signed-off-by: Valentin Rothberg <vrothberg@redhat.com>

Author: vrothberg

libpod/container_validate.go

@@ -3,6 +3,9 @@ package libpod
 import (
 	"fmt"
 
+	"github.com/containers/image/v5/docker"
+	"github.com/containers/image/v5/pkg/shortnames"
+	"github.com/containers/image/v5/transports/alltransports"
 	"github.com/containers/podman/v4/libpod/define"
 	spec "github.com/opencontainers/runtime-spec/specs-go"
 )
@@ -141,5 +144,35 @@ func (c *Container) validate() error {
 	if c.config.HealthCheckOnFailureAction != define.HealthCheckOnFailureActionNone && c.config.HealthCheckConfig == nil {
 		return fmt.Errorf("cannot set on-failure action to %s without a health check", c.config.HealthCheckOnFailureAction.String())
 	}
+
+	if value, exists := c.config.Labels[define.AutoUpdateLabel]; exists {
+		// TODO: we cannot reference pkg/autoupdate here due to
+		// circular dependencies.  It's worth considering moving the
+		// auto-update logic into the libpod package.
+		if value == "registry" || value == "image" {
+			if err := validateAutoUpdateImageReference(c.config.RawImageName); err != nil {
+				return err
+			}
+		}
+	}
+
+	return nil
+}
+
+// validateAutoUpdateImageReference checks if the specified imageName is a
+// fully-qualified image reference to the docker transport. Such a reference
+// includes a domain, name and tag (e.g., quay.io/podman/stable:latest).  The
+// reference may also be prefixed with "docker://" explicitly indicating that
+// it's a reference to the docker transport.
+func validateAutoUpdateImageReference(imageName string) error {
+	// Make sure the input image is a docker.
+	imageRef, err := alltransports.ParseImageName(imageName)
+	if err == nil && imageRef.Transport().Name() != docker.Transport.Name() {
+		return fmt.Errorf("auto updates require the docker image transport but image is of transport %q", imageRef.Transport().Name())
+	} else if err != nil {
+		if shortnames.IsShortName(imageName) {
+			return fmt.Errorf("short name: auto updates require fully-qualified image reference: %q", imageName)
+		}
+	}
 	return nil
 }

libpod/define/autoupdate.go

@@ -0,0 +1,9 @@
+package define
+
+// AutoUpdateLabel denotes the container/pod label key to specify auto-update
+// policies in container labels.
+const AutoUpdateLabel = "io.containers.autoupdate"
+
+// AutoUpdateAuthfileLabel denotes the container label key to specify authfile
+// in container labels.
+const AutoUpdateAuthfileLabel = "io.containers.autoupdate.authfile"

pkg/autoupdate/autoupdate.go

@@ -9,8 +9,6 @@ import (
 	"github.com/containers/common/libimage"
 	"github.com/containers/common/pkg/config"
 	"github.com/containers/image/v5/docker"
-	"github.com/containers/image/v5/docker/reference"
-	"github.com/containers/image/v5/transports/alltransports"
 	"github.com/containers/podman/v4/libpod"
 	"github.com/containers/podman/v4/libpod/define"
 	"github.com/containers/podman/v4/libpod/events"
@@ -21,14 +19,6 @@ import (
 	"github.com/sirupsen/logrus"
 )
 
-// Label denotes the container/pod label key to specify auto-update policies in
-// container labels.
-const Label = "io.containers.autoupdate"
-
-// Label denotes the container label key to specify authfile in
-// container labels.
-const AuthfileLabel = "io.containers.autoupdate.authfile"
-
 // Policy represents an auto-update policy.
 type Policy string
 
@@ -102,32 +92,7 @@ func LookupPolicy(s string) (Policy, error) {
 	return "", fmt.Errorf("invalid auto-update policy %q: valid policies are %+q", s, keys)
 }
 
-// ValidateImageReference checks if the specified imageName is a fully-qualified
-// image reference to the docker transport (without digest).  Such a reference
-// includes a domain, name and tag (e.g., quay.io/podman/stable:latest).  The
-// reference may also be prefixed with "docker://" explicitly indicating that
-// it's a reference to the docker transport.
-func ValidateImageReference(imageName string) error {
-	// Make sure the input image is a docker.
-	imageRef, err := alltransports.ParseImageName(imageName)
-	if err == nil && imageRef.Transport().Name() != docker.Transport.Name() {
-		return fmt.Errorf("auto updates require the docker image transport but image is of transport %q", imageRef.Transport().Name())
-	} else if err != nil {
-		repo, err := reference.Parse(imageName)
-		if err != nil {
-			return fmt.Errorf("enforcing fully-qualified docker transport reference for auto updates: %w", err)
-		}
-		if _, ok := repo.(reference.NamedTagged); !ok {
-			return fmt.Errorf("auto updates require fully-qualified image references (no tag): %q", imageName)
-		}
-		if _, ok := repo.(reference.Digested); ok {
-			return fmt.Errorf("auto updates require fully-qualified image references without digest: %q", imageName)
-		}
-	}
-	return nil
-}
-
-// AutoUpdate looks up containers with a specified auto-update policy and acts
+/// AutoUpdate looks up containers with a specified auto-update policy and acts
 // accordingly.
 //
 // If the policy is set to PolicyRegistryImage, it checks if the image
@@ -418,7 +383,7 @@ func (u *updater) assembleTasks(ctx context.Context) []error {
 		// Check the container's auto-update policy which is configured
 		// as a label.
 		labels := ctr.Labels()
-		value, exists := labels[Label]
+		value, exists := labels[define.AutoUpdateLabel]
 		if !exists {
 			continue
 		}
@@ -454,7 +419,7 @@ func (u *updater) assembleTasks(ctx context.Context) []error {
 		}
 
 		t := task{
-			authfile:     labels[AuthfileLabel],
+			authfile:     labels[define.AutoUpdateAuthfileLabel],
 			auto:         u,
 			container:    ctr,
 			policy:       policy,

pkg/autoupdate/autoupdate_test.go

@@ -19,7 +19,6 @@ import (
 	"github.com/containers/image/v5/types"
 	"github.com/containers/podman/v4/libpod"
 	"github.com/containers/podman/v4/libpod/define"
-	"github.com/containers/podman/v4/pkg/autoupdate"
 	"github.com/containers/podman/v4/pkg/domain/entities"
 	v1apps "github.com/containers/podman/v4/pkg/k8s.io/api/apps/v1"
 	v1 "github.com/containers/podman/v4/pkg/k8s.io/api/core/v1"
@@ -800,8 +799,8 @@ func (ic *ContainerEngine) getImageAndLabelInfo(ctx context.Context, cwd string,
 		}
 	}
 
-	setLabel(autoupdate.Label)
-	setLabel(autoupdate.AuthfileLabel)
+	setLabel(define.AutoUpdateLabel)
+	setLabel(define.AutoUpdateAuthfileLabel)
 
 	return pulledImage, labels, nil
 }

pkg/domain/infra/abi/play.go

@@ -133,6 +133,26 @@ function _confirm_update() {
     die "Timed out waiting for $cname to update; old IID=$old_iid"
 }
 
+@test "podman auto-update - validate input" {
+    # Fully-qualified image reference is required
+    run_podman create --label io.containers.autoupdate=registry $IMAGE
+    run_podman rm -f "$output"
+
+    # Short name does not work
+    shortname="shortname:latest"
+    run_podman image tag $IMAGE $shortname
+    run_podman 125 create --label io.containers.autoupdate=registry $shortname
+    is "$output" "Error: short name: auto updates require fully-qualified image reference: \"$shortname\""
+
+    # Requires docker (or no) transport
+    archive=$PODMAN_TMPDIR/archive.tar
+    run_podman save -o $archive $IMAGE
+    run_podman 125 create --label io.containers.autoupdate=registry docker-archive:$archive
+    is "$output" ".*Error: auto updates require the docker image transport but image is of transport \"docker-archive\""
+
+    run_podman rmi $shortname
+}
+
 # This test can fail in dev. environment because of SELinux.
 # quick fix: chcon -t container_runtime_exec_t ./bin/podman
 @test "podman auto-update - label io.containers.autoupdate=image" {