validation: add a new test for NSInheritWithoutType

This test is to check for NSInheritWithoutType, i.e. "If a namespace
type is not specified in the namespaces array, the container MUST
inherit the runtime namespace of that type".

See also opencontainers#572

Signed-off-by: Dongsu Park <dongsu@kinvolk.io>

generate/generate.go

@@ -370,6 +370,14 @@ func (g *Generator) RemoveAnnotation(key string) {
 	delete(g.Config.Annotations, key)
 }
 
+// RemoveHostname removes g.Config.Hostname, setting it to an empty string.
+func (g *Generator) RemoveHostname() {
+	if g.Config == nil {
+		return
+	}
+	g.Config.Hostname = ""
+}
+
 // SetProcessConsoleSize sets g.Config.Process.ConsoleSize.
 func (g *Generator) SetProcessConsoleSize(width, height uint) {
 	g.initConfigProcessConsoleSize()

validation/linux_ns_itype.go

@@ -0,0 +1,88 @@
+package main
+
+import (
+	"fmt"
+	"os"
+	"path/filepath"
+	"runtime"
+
+	"github.com/mndrix/tap-go"
+	rspec "github.com/opencontainers/runtime-spec/specs-go"
+	"github.com/opencontainers/runtime-tools/specerror"
+	"github.com/opencontainers/runtime-tools/validation/util"
+)
+
+func testNamespaceInheritType(t *tap.T) error {
+	g, err := util.GetDefaultGenerator()
+	if err != nil {
+		return err
+	}
+
+	// Obtain a map for host (runtime) namespace, and remove every namespace
+	// from the generated config, to be able to see if each container namespace
+	// becomes inherited from its corresponding host namespace.
+	hostNsPath := fmt.Sprintf("/proc/%d/ns", os.Getpid())
+	hostNsInodes := map[string]string{}
+	for _, nsName := range util.ProcNamespaces {
+		nsInode, err := os.Readlink(filepath.Join(hostNsPath, nsName))
+		if err != nil {
+			return err
+		}
+		hostNsInodes[nsName] = nsInode
+
+		if err := g.RemoveLinuxNamespace(util.GetRuntimeToolsNamespace(nsName)); err != nil {
+			return err
+		}
+	}
+
+	// We need to remove hostname to avoid test failures when not creating UTS namespace
+	g.RemoveHostname()
+
+	err = util.RuntimeOutsideValidate(g, func(config *rspec.Spec, state *rspec.State) error {
+		containerNsPath := fmt.Sprintf("/proc/%d/ns", state.Pid)
+
+		for _, nsName := range util.ProcNamespaces {
+			nsInode, err := os.Readlink(filepath.Join(containerNsPath, nsName))
+			if err != nil {
+				return err
+			}
+
+			t.Ok(hostNsInodes[nsName] == nsInode, fmt.Sprintf("inherit namespace %s without type", nsName))
+			if hostNsInodes[nsName] != nsInode {
+				specErr := specerror.NewError(specerror.NSInheritWithoutType,
+					fmt.Errorf("namespace %s (inode %s) does not inherit runtime namespace %s", nsName, nsInode, hostNsInodes[nsName]),
+					rspec.Version)
+				diagnostic := map[string]interface{}{
+					"expected":       hostNsInodes[nsName],
+					"actual":         nsInode,
+					"namespace type": nsName,
+					"level":          specErr.(*specerror.Error).Err.Level,
+					"reference":      specErr.(*specerror.Error).Err.Reference,
+				}
+				t.YAML(diagnostic)
+
+				continue
+			}
+		}
+
+		return nil
+	})
+
+	return err
+}
+
+func main() {
+	t := tap.New()
+	t.Header(0)
+
+	if "linux" != runtime.GOOS {
+		t.Skip(1, fmt.Sprintf("linux-specific namespace test"))
+	}
+
+	err := testNamespaceInheritType(t)
+	if err != nil {
+		util.Fatal(err)
+	}
+
+	t.AutoPlan()
+}

validation/util/linux_namespace.go

@@ -12,3 +12,19 @@ var ProcNamespaces = []string{
 	"user",
 	"uts",
 }
+
+// GetRuntimeToolsNamespace converts a namespace type string for /proc into
+// a string for runtime-tools. It deals with exceptional cases of "net" and
+// "mnt", because those strings cannot be recognized by mapStrToNamespace(),
+// which actually expects "network" and "mount" respectively.
+func GetRuntimeToolsNamespace(ns string) string {
+	switch ns {
+	case "net":
+		return "network"
+	case "mnt":
+		return "mount"
+	}
+
+	// In other cases, return just the original string
+	return ns
+}