Update registry server to support repository class

Use whitelist of allowed repository classes to enforce.
By default all repository classes are allowed.

Add authorized resources to context after authorization.

Signed-off-by: Derek McGowan <derek@mcgstyle.net> (github: dmcgowan)

configuration/configuration.go

@@ -203,6 +203,19 @@ type Configuration struct {
 			} `yaml:"urls,omitempty"`
 		} `yaml:"manifests,omitempty"`
 	} `yaml:"validation,omitempty"`
+
+	// Policy configures registry policy options.
+	Policy struct {
+		// Repository configures policies for repositories
+		Repository struct {
+			// Classes is a list of repository classes which the
+			// registry allows content for. This class is matched
+			// against the configuration media type inside uploaded
+			// manifests. When non-empty, the registry will enforce
+			// the class in authorized resources.
+			Classes []string `yaml:"classes"`
+		} `yaml:"repository,omitempty"`
+	} `yaml:"policy,omitempty"`
 }
 
 // LogHook is composed of hook Level and Type.

registry/auth/auth.go

@@ -136,6 +136,39 @@ func (uic userInfoContext) Value(key interface{}) interface{} {
 	return uic.Context.Value(key)
 }
 
+// WithResources returns a context with the authorized resources.
+func WithResources(ctx context.Context, resources []Resource) context.Context {
+	return resourceContext{
+		Context:   ctx,
+		resources: resources,
+	}
+}
+
+type resourceContext struct {
+	context.Context
+	resources []Resource
+}
+
+type resourceKey struct{}
+
+func (rc resourceContext) Value(key interface{}) interface{} {
+	if key == (resourceKey{}) {
+		return rc.resources
+	}
+
+	return rc.Context.Value(key)
+}
+
+// AuthorizedResources returns the list of resources which have
+// been authorized for this request.
+func AuthorizedResources(ctx context.Context) []Resource {
+	if resources, ok := ctx.Value(resourceKey{}).([]Resource); ok {
+		return resources
+	}
+
+	return nil
+}
+
 // InitFunc is the type of an AccessController factory function and is used
 // to register the constructor for different AccesController backends.
 type InitFunc func(options map[string]interface{}) (AccessController, error)

registry/auth/token/accesscontroller.go

@@ -261,6 +261,8 @@ func (ac *accessController) Authorized(ctx context.Context, accessItems ...auth.
 		}
 	}
 
+	ctx = auth.WithResources(ctx, token.resources())
+
 	return auth.WithUser(ctx, auth.UserInfo{Name: token.Claims.Subject}), nil
 }
 

registry/auth/token/token.go

@@ -34,7 +34,7 @@ var (
 // ResourceActions stores allowed actions on a named and typed resource.
 type ResourceActions struct {
 	Type    string   `json:"type"`
-	Class   string   `json:"class"`
+	Class   string   `json:"class,omitempty"`
 	Name    string   `json:"name"`
 	Actions []string `json:"actions"`
 }
@@ -350,6 +350,29 @@ func (t *Token) accessSet() accessSet {
 	return accessSet
 }
 
+func (t *Token) resources() []auth.Resource {
+	if t.Claims == nil {
+		return nil
+	}
+
+	resourceSet := map[auth.Resource]struct{}{}
+	for _, resourceActions := range t.Claims.Access {
+		resource := auth.Resource{
+			Type:  resourceActions.Type,
+			Class: resourceActions.Class,
+			Name:  resourceActions.Name,
+		}
+		resourceSet[resource] = struct{}{}
+	}
+
+	resources := make([]auth.Resource, 0, len(resourceSet))
+	for resource := range resourceSet {
+		resources = append(resources, resource)
+	}
+
+	return resources
+}
+
 func (t *Token) compactRaw() string {
 	return fmt.Sprintf("%s.%s", t.Raw, joseBase64UrlEncode(t.Signature))
 }

registry/handlers/images.go

@@ -15,6 +15,7 @@ import (
 	"github.com/docker/distribution/reference"
 	"github.com/docker/distribution/registry/api/errcode"
 	"github.com/docker/distribution/registry/api/v2"
+	"github.com/docker/distribution/registry/auth"
 	"github.com/gorilla/handlers"
 )
 
@@ -269,6 +270,12 @@ func (imh *imageManifestHandler) PutImageManifest(w http.ResponseWriter, r *http
 	if imh.Tag != "" {
 		options = append(options, distribution.WithTag(imh.Tag))
 	}
+
+	if err := imh.applyResourcePolicy(manifest); err != nil {
+		imh.Errors = append(imh.Errors, err)
+		return
+	}
+
 	_, err = manifests.Put(imh, manifest, options...)
 	if err != nil {
 		// TODO(stevvooe): These error handling switches really need to be
@@ -339,6 +346,73 @@ func (imh *imageManifestHandler) PutImageManifest(w http.ResponseWriter, r *http
 	w.WriteHeader(http.StatusCreated)
 }
 
+// applyResourcePolicy checks whether the resource class matches what has
+// been authorized and allowed by the policy configuration.
+func (imh *imageManifestHandler) applyResourcePolicy(manifest distribution.Manifest) error {
+	allowedClasses := imh.App.Config.Policy.Repository.Classes
+	if len(allowedClasses) == 0 {
+		return nil
+	}
+
+	var class string
+	switch m := manifest.(type) {
+	case *schema1.SignedManifest:
+		class = "image"
+	case *schema2.DeserializedManifest:
+		switch m.Config.MediaType {
+		case schema2.MediaTypeConfig:
+			class = "image"
+		case schema2.MediaTypePluginConfig:
+			class = "plugin"
+		default:
+			message := fmt.Sprintf("unknown manifest class for %s", m.Config.MediaType)
+			return errcode.ErrorCodeDenied.WithMessage(message)
+		}
+	}
+
+	if class == "" {
+		return nil
+	}
+
+	// Check to see if class is allowed in registry
+	var allowedClass bool
+	for _, c := range allowedClasses {
+		if class == c {
+			allowedClass = true
+			break
+		}
+	}
+	if !allowedClass {
+		message := fmt.Sprintf("registry does not allow %s manifest", class)
+		return errcode.ErrorCodeDenied.WithMessage(message)
+	}
+
+	resources := auth.AuthorizedResources(imh)
+	n := imh.Repository.Named().Name()
+
+	var foundResource bool
+	for _, r := range resources {
+		if r.Name == n {
+			if r.Class == "" {
+				r.Class = "image"
+			}
+			if r.Class == class {
+				return nil
+			}
+			foundResource = true
+		}
+	}
+
+	// resource was found but no matching class was found
+	if foundResource {
+		message := fmt.Sprintf("repository not authorized for %s manifest", class)
+		return errcode.ErrorCodeDenied.WithMessage(message)
+	}
+
+	return nil
+
+}
+
 // DeleteImageManifest removes the manifest with the given digest from the registry.
 func (imh *imageManifestHandler) DeleteImageManifest(w http.ResponseWriter, r *http.Request) {
 	ctxu.GetLogger(imh).Debug("DeleteImageManifest")