fix bug: media types mismatch in manifest

cmd/oci-image-tool/validate.go

@@ -16,6 +16,7 @@ package main
 
 import (
 	"fmt"
+	"io/ioutil"
 	"log"
 	"os"
 	"strings"
@@ -138,6 +139,9 @@ func (v *validateCmd) validatePath(name string) error {
 
 	switch typ {
 	case typeManifest:
+		if err := validManifestfile(name); err != nil {
+			return errors.Wrap(err, "invalid manifest format")
+		}
 		return schema.MediaTypeManifest.Validate(f)
 	case typeManifestList:
 		return schema.MediaTypeManifestList.Validate(f)
@@ -147,3 +151,19 @@ func (v *validateCmd) validatePath(name string) error {
 
 	return fmt.Errorf("type %q unimplemented", typ)
 }
+
+func validManifestfile(name string) error {
+	f, err := os.Open(name)
+	if err != nil {
+		return errors.Wrap(err, "unable to open manifest")
+	}
+	defer f.Close()
+	buf, err := ioutil.ReadAll(f)
+	if err != nil {
+		return errors.Wrap(err, "unable to read manifest")
+	}
+	if err := image.ValidInternalMediaType(buf); err != nil {
+		return errors.Wrapf(err, "%s: manifest validation failed", name)
+	}
+	return nil
+}

image/manifest.go

@@ -51,6 +51,10 @@ func findManifest(w walker, d *descriptor) (*manifest, error) {
 			return errors.Wrapf(err, "%s: error reading manifest", path)
 		}
 
+		if err := ValidInternalMediaType(buf); err != nil {
+			return errors.Wrapf(err, "%s: manifest validation failed", path)
+		}
+
 		if err := schema.MediaTypeManifest.Validate(bytes.NewReader(buf)); err != nil {
 			return errors.Wrapf(err, "%s: manifest validation failed", path)
 		}
@@ -240,3 +244,33 @@ loop:
 	}
 	return nil
 }
+
+// ValidInternalMediaType validate the manifest's internal
+// fields mediatype such as config and layers, to make sure
+// they match to spec definition, or returns an error if
+// the validation failed.
+func ValidInternalMediaType(buf []byte) error {
+	header := struct {
+		Config struct {
+			MediaType string `json:"mediaType"`
+		} `json:"config"`
+		Layers []struct {
+			MediaType string `json:"mediaType"`
+		} `json:"layers"`
+	}{}
+
+	if err := json.NewDecoder(bytes.NewReader(buf)).Decode(&header); err != nil {
+		return errors.Wrap(err, "manifest format mismatch")
+	}
+	if header.Config.MediaType != string(schema.MediaTypeImageConfig) &&
+		header.Config.MediaType != string(schema.MediaTypeDockerImageConfig) {
+		return fmt.Errorf("illegal config mediaType: %s", header.Config.MediaType)
+	}
+	for _, layer := range header.Layers {
+		if layer.MediaType != string(schema.MediaTypeImageLayer) &&
+			layer.MediaType != string(schema.MediaTypeDockerImageLayer) {
+			return fmt.Errorf("illegal layer mediaType: %s", layer.MediaType)
+		}
+	}
+	return nil
+}

schema/schema.go

@@ -22,11 +22,13 @@ import (
 
 // Media types for the OCI image formats
 const (
-	MediaTypeDescriptor   Validator     = v1.MediaTypeDescriptor
-	MediaTypeManifest     Validator     = v1.MediaTypeImageManifest
-	MediaTypeManifestList Validator     = v1.MediaTypeImageManifestList
-	MediaTypeImageConfig  Validator     = v1.MediaTypeImageConfig
-	MediaTypeImageLayer   unimplemented = v1.MediaTypeImageLayer
+	MediaTypeDescriptor        Validator     = v1.MediaTypeDescriptor
+	MediaTypeManifest          Validator     = v1.MediaTypeImageManifest
+	MediaTypeManifestList      Validator     = v1.MediaTypeImageManifestList
+	MediaTypeImageConfig       Validator     = v1.MediaTypeImageConfig
+	MediaTypeImageLayer        unimplemented = v1.MediaTypeImageLayer
+	MediaTypeDockerImageConfig Validator     = "application/vnd.docker.container.image.v1+json"
+	MediaTypeDockerImageLayer  unimplemented = "application/vnd.docker.image.rootfs.diff.tar.gzip"
 )
 
 var (