Add util to validate namespaced names

pkg/api/validation/validation.go

@@ -385,19 +385,7 @@ func ValidatePodSpec(spec *api.PodSpec) errs.ValidationErrorList {
 func validateLabels(labels map[string]string, field string) errs.ValidationErrorList {
 	allErrs := errs.ValidationErrorList{}
 	for k := range labels {
-		var n, ns string
-		parts := strings.Split(k, "/")
-		switch len(parts) {
-		case 1:
-			n = parts[0]
-		case 2:
-			ns = parts[0]
-			n = parts[1]
-		default:
-			allErrs = append(allErrs, errs.NewFieldInvalid(field, k, ""))
-			continue
-		}
-		if (ns != "" && !util.IsDNSSubdomain(ns)) || !util.IsDNSLabel(n) {
+		if !util.IsQualifiedName(k) {
 			allErrs = append(allErrs, errs.NewFieldInvalid(field, k, ""))
 		}
 	}