diff options
Diffstat (limited to 'runsc/container/container_test.go')
| -rw-r--r-- | runsc/container/container_test.go | 669 |
1 files changed, 669 insertions, 0 deletions
diff --git a/runsc/container/container_test.go b/runsc/container/container_test.go new file mode 100644 index 000000000..67efd2f9e --- /dev/null +++ b/runsc/container/container_test.go @@ -0,0 +1,669 @@ +// Copyright 2018 Google Inc. +// +// Licensed under the Apache License, Version 2.0 (the "License"); +// you may not use this file except in compliance with the License. +// You may obtain a copy of the License at +// +// http://www.apache.org/licenses/LICENSE-2.0 +// +// Unless required by applicable law or agreed to in writing, software +// distributed under the License is distributed on an "AS IS" BASIS, +// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. +// See the License for the specific language governing permissions and +// limitations under the License. + +package container_test + +import ( + "encoding/json" + "fmt" + "io" + "io/ioutil" + "os" + "os/signal" + "path/filepath" + "reflect" + "strings" + "syscall" + "testing" + "time" + + "context" + "flag" + "github.com/google/subcommands" + specs "github.com/opencontainers/runtime-spec/specs-go" + "golang.org/x/sys/unix" + "gvisor.googlesource.com/gvisor/pkg/abi/linux" + "gvisor.googlesource.com/gvisor/pkg/log" + "gvisor.googlesource.com/gvisor/pkg/sentry/control" + "gvisor.googlesource.com/gvisor/pkg/sentry/kernel/auth" + "gvisor.googlesource.com/gvisor/pkg/unet" + "gvisor.googlesource.com/gvisor/runsc/boot" + "gvisor.googlesource.com/gvisor/runsc/cmd" + "gvisor.googlesource.com/gvisor/runsc/container" +) + +func init() { + log.SetLevel(log.Debug) +} + +// writeSpec writes the spec to disk in the given directory. +func writeSpec(dir string, spec *specs.Spec) error { + b, err := json.Marshal(spec) + if err != nil { + return err + } + return ioutil.WriteFile(filepath.Join(dir, "config.json"), b, 0755) +} + +// newSpecWithArgs creates a simple spec with the given args suitable for use +// in tests. +func newSpecWithArgs(args ...string) *specs.Spec { + spec := &specs.Spec{ + // The host filesystem root is the container root. + Root: &specs.Root{ + Path: "/", + Readonly: true, + }, + Process: &specs.Process{ + Args: args, + Env: []string{ + "PATH=" + os.Getenv("PATH"), + }, + }, + } + return spec +} + +// shutdownSignal will be sent to the sandbox in order to shut down cleanly. +const shutdownSignal = syscall.SIGUSR2 + +// setupContainer creates a bundle and root dir for the container, generates a +// test config, and writes the spec to config.json in the bundle dir. +func setupContainer(spec *specs.Spec) (rootDir, bundleDir string, conf *boot.Config, err error) { + rootDir, err = ioutil.TempDir("", "containers") + if err != nil { + return "", "", nil, fmt.Errorf("error creating root dir: %v", err) + } + + bundleDir, err = ioutil.TempDir("", "bundle") + if err != nil { + return "", "", nil, fmt.Errorf("error creating bundle dir: %v", err) + } + + if err = writeSpec(bundleDir, spec); err != nil { + return "", "", nil, fmt.Errorf("error writing spec: %v", err) + } + + conf = &boot.Config{ + RootDir: rootDir, + Network: boot.NetworkNone, + // Don't add flags when calling subprocesses, since the test + // runner does not know about all the flags. We control the + // Config in the subprocess anyways, so it does not matter. + TestModeNoFlags: true, + } + + return rootDir, bundleDir, conf, nil +} + +// uniqueContainerID generates a unique container id for each test. +// +// The container id is used to create an abstract unix domain socket, which must +// be unique. While the container forbids creating two containers with the same +// name, sometimes between test runs the socket does not get cleaned up quickly +// enough, causing container creation to fail. +func uniqueContainerID() string { + return fmt.Sprintf("test-container-%d", time.Now().UnixNano()) +} + +// waitForProcessList waits for the given process list to show up in the container. +func waitForProcessList(s *container.Container, expected []*control.Process) error { + var got []*control.Process + for start := time.Now(); time.Now().Sub(start) < 10*time.Second; { + var err error + got, err := s.Processes() + if err != nil { + return fmt.Errorf("error getting process data from container: %v", err) + } + if procListsEqual(got, expected) { + return nil + } + // Process might not have started, try again... + time.Sleep(10 * time.Millisecond) + } + return fmt.Errorf("container got process list: %s, want: %s", procListToString(got), procListToString(expected)) +} + +// TestLifecycle tests the basic Create/Start/Signal/Destroy container lifecycle. +// It verifies after each step that the container can be loaded from disk, and +// has the correct status. +func TestLifecycle(t *testing.T) { + // The container will just sleep for a long time. We will kill it before + // it finishes sleeping. + spec := newSpecWithArgs("sleep", "100") + + rootDir, bundleDir, conf, err := setupContainer(spec) + if err != nil { + t.Fatalf("error setting up container: %v", err) + } + defer os.RemoveAll(rootDir) + defer os.RemoveAll(bundleDir) + + // expectedPL lists the expected process state of the container. + expectedPL := []*control.Process{ + { + UID: 0, + PID: 1, + PPID: 0, + C: 0, + Cmd: "sleep", + }, + } + // Create the container. + id := uniqueContainerID() + if _, err := container.Create(id, spec, conf, bundleDir, "", ""); err != nil { + t.Fatalf("error creating container: %v", err) + } + // Load the container from disk and check the status. + s, err := container.Load(rootDir, id) + if err != nil { + t.Fatalf("error loading container: %v", err) + } + if got, want := s.Status, container.Created; got != want { + t.Errorf("container status got %v, want %v", got, want) + } + + // List should return the container id. + ids, err := container.List(rootDir) + if err != nil { + t.Fatalf("error listing containers: %v", err) + } + if got, want := ids, []string{id}; !reflect.DeepEqual(got, want) { + t.Errorf("container list got %v, want %v", got, want) + } + + // Start the container. + if err := s.Start(conf); err != nil { + t.Fatalf("error starting container: %v", err) + } + // Load the container from disk and check the status. + s, err = container.Load(rootDir, id) + if err != nil { + t.Fatalf("error loading container: %v", err) + } + if got, want := s.Status, container.Running; got != want { + t.Errorf("container status got %v, want %v", got, want) + } + + // Verify that "sleep 100" is running. + if err := waitForProcessList(s, expectedPL); err != nil { + t.Error(err) + } + + // Send the container a signal, which we catch and use to cleanly + // shutdown. + if err := s.Signal(shutdownSignal); err != nil { + t.Fatalf("error sending signal %v to container: %v", shutdownSignal, err) + } + // Wait for it to die. + if _, err := s.Wait(); err != nil { + t.Fatalf("error waiting on container: %v", err) + } + // Load the container from disk and check the status. + s, err = container.Load(rootDir, id) + if err != nil { + t.Fatalf("error loading container: %v", err) + } + if got, want := s.Status, container.Stopped; got != want { + t.Errorf("container status got %v, want %v", got, want) + } + + // Destroy the container. + if err := s.Destroy(); err != nil { + t.Fatalf("error destroying container: %v", err) + } + + // List should not return the container id. + ids, err = container.List(rootDir) + if err != nil { + t.Fatalf("error listing containers: %v", err) + } + if len(ids) != 0 { + t.Errorf("expected container list to be empty, but got %v", ids) + } + + // Loading the container by id should fail. + if _, err = container.Load(rootDir, id); err == nil { + t.Errorf("expected loading destroyed container to fail, but it did not") + } +} + +// Test the we can execute the application with different path formats. +func TestExePath(t *testing.T) { + for _, test := range []struct { + path string + success bool + }{ + {path: "true", success: true}, + {path: "bin/true", success: true}, + {path: "/bin/true", success: true}, + {path: "thisfiledoesntexit", success: false}, + {path: "bin/thisfiledoesntexit", success: false}, + {path: "/bin/thisfiledoesntexit", success: false}, + } { + spec := newSpecWithArgs(test.path) + rootDir, bundleDir, conf, err := setupContainer(spec) + if err != nil { + t.Fatalf("exec: %s, error setting up container: %v", test.path, err) + } + + ws, err := container.Run(uniqueContainerID(), spec, conf, bundleDir, "", "") + + os.RemoveAll(rootDir) + os.RemoveAll(bundleDir) + + if test.success { + if err != nil { + t.Errorf("exec: %s, error running container: %v", test.path, err) + } + if ws.ExitStatus() != 0 { + t.Errorf("exec: %s, got exit status %v want %v", test.path, ws.ExitStatus(), 0) + } + } else { + if err == nil { + t.Errorf("exec: %s, got: no error, want: error", test.path) + } + } + } +} + +// Test the we can retrieve the application exit status from the container. +func TestAppExitStatus(t *testing.T) { + // First container will succeed. + succSpec := newSpecWithArgs("true") + + rootDir, bundleDir, conf, err := setupContainer(succSpec) + if err != nil { + t.Fatalf("error setting up container: %v", err) + } + defer os.RemoveAll(rootDir) + defer os.RemoveAll(bundleDir) + + ws, err := container.Run(uniqueContainerID(), succSpec, conf, bundleDir, "", "") + if err != nil { + t.Fatalf("error running container: %v", err) + } + if ws.ExitStatus() != 0 { + t.Errorf("got exit status %v want %v", ws.ExitStatus(), 0) + } + + // Second container exits with non-zero status. + wantStatus := 123 + errSpec := newSpecWithArgs("bash", "-c", fmt.Sprintf("exit %d", wantStatus)) + + rootDir2, bundleDir2, conf, err := setupContainer(errSpec) + if err != nil { + t.Fatalf("error setting up container: %v", err) + } + defer os.RemoveAll(rootDir2) + defer os.RemoveAll(bundleDir2) + + ws, err = container.Run(uniqueContainerID(), succSpec, conf, bundleDir2, "", "") + if err != nil { + t.Fatalf("error running container: %v", err) + } + if ws.ExitStatus() != wantStatus { + t.Errorf("got exit status %v want %v", ws.ExitStatus(), wantStatus) + } +} + +// TestExec verifies that a container can exec a new program. +func TestExec(t *testing.T) { + const uid = 343 + spec := newSpecWithArgs("sleep", "100") + + rootDir, bundleDir, conf, err := setupContainer(spec) + if err != nil { + t.Fatalf("error setting up container: %v", err) + } + defer os.RemoveAll(rootDir) + defer os.RemoveAll(bundleDir) + + // Create and start the container. + s, err := container.Create(uniqueContainerID(), spec, conf, bundleDir, "", "") + if err != nil { + t.Fatalf("error creating container: %v", err) + } + defer s.Destroy() + if err := s.Start(conf); err != nil { + t.Fatalf("error starting container: %v", err) + } + + // expectedPL lists the expected process state of the container. + expectedPL := []*control.Process{ + { + UID: 0, + PID: 1, + PPID: 0, + C: 0, + Cmd: "sleep", + }, + { + UID: uid, + PID: 2, + PPID: 0, + C: 0, + Cmd: "sleep", + }, + } + + // Verify that "sleep 100" is running. + if err := waitForProcessList(s, expectedPL[:1]); err != nil { + t.Error(err) + } + + execArgs := control.ExecArgs{ + Filename: "/bin/sleep", + Argv: []string{"sleep", "5"}, + Envv: []string{"PATH=" + os.Getenv("PATH")}, + WorkingDirectory: "/", + KUID: uid, + } + + // Verify that "sleep 100" and "sleep 5" are running after exec. + // First, start running exec (whick blocks). + status := make(chan error, 1) + go func() { + exitStatus, err := s.Execute(&execArgs) + if err != nil { + status <- err + } else if exitStatus != 0 { + status <- fmt.Errorf("failed with exit status: %v", exitStatus) + } else { + status <- nil + } + }() + + if err := waitForProcessList(s, expectedPL); err != nil { + t.Fatal(err) + } + + // Ensure that exec finished without error. + select { + case <-time.After(10 * time.Second): + t.Fatalf("container timed out waiting for exec to finish.") + case st := <-status: + if st != nil { + t.Errorf("container failed to exec %v: %v", execArgs, err) + } + } +} + +// TestCapabilities verifies that: +// - Running exec as non-root UID and GID will result in an error (because the +// executable file can't be read). +// - Running exec as non-root with CAP_DAC_OVERRIDE succeeds because it skips +// this check. +func TestCapabilities(t *testing.T) { + const uid = 343 + const gid = 2401 + spec := newSpecWithArgs("sleep", "100") + + // We generate files in the host temporary directory. + spec.Mounts = append(spec.Mounts, specs.Mount{ + Destination: os.TempDir(), + Source: os.TempDir(), + Type: "bind", + }) + + rootDir, bundleDir, conf, err := setupContainer(spec) + if err != nil { + t.Fatalf("error setting up container: %v", err) + } + defer os.RemoveAll(rootDir) + defer os.RemoveAll(bundleDir) + + // Create and start the container. + s, err := container.Create(uniqueContainerID(), spec, conf, bundleDir, "", "") + if err != nil { + t.Fatalf("error creating container: %v", err) + } + defer s.Destroy() + if err := s.Start(conf); err != nil { + t.Fatalf("error starting container: %v", err) + } + + // expectedPL lists the expected process state of the container. + expectedPL := []*control.Process{ + { + UID: 0, + PID: 1, + PPID: 0, + C: 0, + Cmd: "sleep", + }, + { + UID: uid, + PID: 2, + PPID: 0, + C: 0, + Cmd: "exe", + }, + } + if err := waitForProcessList(s, expectedPL[:1]); err != nil { + t.Fatalf("Failed to wait for sleep to start, err: %v", err) + } + + // Create an executable that can't be run with the specified UID:GID. + // This shouldn't be callable within the container until we add the + // CAP_DAC_OVERRIDE capability to skip the access check. + exePath := filepath.Join(rootDir, "exe") + if err := ioutil.WriteFile(exePath, []byte("#!/bin/sh\necho hello"), 0770); err != nil { + t.Fatalf("couldn't create executable: %v", err) + } + defer os.Remove(exePath) + + // Need to traverse the intermediate directory. + os.Chmod(rootDir, 0755) + + execArgs := control.ExecArgs{ + Filename: exePath, + Argv: []string{exePath}, + Envv: []string{"PATH=" + os.Getenv("PATH")}, + WorkingDirectory: "/", + KUID: uid, + KGID: gid, + Capabilities: &auth.TaskCapabilities{}, + } + + // "exe" should fail because we don't have the necessary permissions. + if _, err := s.Execute(&execArgs); err == nil { + t.Fatalf("container executed without error, but an error was expected") + } + + // Now we run with the capability enabled and should succeed. + execArgs.Capabilities = &auth.TaskCapabilities{ + EffectiveCaps: auth.CapabilitySetOf(linux.CAP_DAC_OVERRIDE), + } + // "exe" should not fail this time. + if _, err := s.Execute(&execArgs); err != nil { + t.Fatalf("container failed to exec %v: %v", execArgs, err) + } +} + +// Test that an tty FD is sent over the console socket if one is provided. +func TestConsoleSocket(t *testing.T) { + spec := newSpecWithArgs("true") + rootDir, bundleDir, conf, err := setupContainer(spec) + if err != nil { + t.Fatalf("error setting up container: %v", err) + } + defer os.RemoveAll(rootDir) + defer os.RemoveAll(bundleDir) + + // Create a named socket and start listening. We use a relative path + // to avoid overflowing the unix path length limit (108 chars). + socketPath := filepath.Join(bundleDir, "socket") + cwd, err := os.Getwd() + if err != nil { + t.Fatalf("error getting cwd: %v", err) + } + socketRelPath, err := filepath.Rel(cwd, socketPath) + if err != nil { + t.Fatalf("error getting relative path for %q from cwd %q: %v", socketPath, cwd, err) + } + if len(socketRelPath) > len(socketPath) { + socketRelPath = socketPath + } + srv, err := unet.BindAndListen(socketRelPath, false) + if err != nil { + t.Fatalf("error binding and listening to socket %q: %v", socketPath, err) + } + defer os.Remove(socketPath) + + // Create the container and pass the socket name. + id := uniqueContainerID() + s, err := container.Create(id, spec, conf, bundleDir, socketRelPath, "") + if err != nil { + t.Fatalf("error creating container: %v", err) + } + + // Open the othe end of the socket. + sock, err := srv.Accept() + if err != nil { + t.Fatalf("error accepting socket connection: %v", err) + } + + // Allow 3 fds to be received. We only expect 1. + r := sock.Reader(true /* blocking */) + r.EnableFDs(1) + + // The socket is closed right after sending the FD, so EOF is + // an allowed error. + b := [][]byte{{}} + if _, err := r.ReadVec(b); err != nil && err != io.EOF { + t.Fatalf("error reading from socket connection: %v", err) + } + + // We should have gotten a control message. + fds, err := r.ExtractFDs() + if err != nil { + t.Fatalf("error extracting fds from socket connection: %v", err) + } + if len(fds) != 1 { + t.Fatalf("got %d fds from socket, wanted 1", len(fds)) + } + + // Verify that the fd is a terminal. + if _, err := unix.IoctlGetTermios(fds[0], unix.TCGETS); err != nil { + t.Errorf("fd is not a terminal (ioctl TGGETS got %v)", err) + } + + // Shut it down. + if err := s.Destroy(); err != nil { + t.Fatalf("error destroying container: %v", err) + } + + // Close socket. + if err := srv.Close(); err != nil { + t.Fatalf("error destroying container: %v", err) + } +} + +func TestSpecUnsupported(t *testing.T) { + spec := newSpecWithArgs("/bin/true") + spec.Process.SelinuxLabel = "somelabel" + + // These are normally set by docker and will just cause warnings to be logged. + spec.Process.ApparmorProfile = "someprofile" + spec.Linux = &specs.Linux{Seccomp: &specs.LinuxSeccomp{}} + + rootDir, bundleDir, conf, err := setupContainer(spec) + if err != nil { + t.Fatalf("error setting up container: %v", err) + } + defer os.RemoveAll(rootDir) + defer os.RemoveAll(bundleDir) + + id := uniqueContainerID() + _, err = container.Create(id, spec, conf, bundleDir, "", "") + if err == nil || !strings.Contains(err.Error(), "is not supported") { + t.Errorf("container.Create() wrong error, got: %v, want: *is not supported, spec.Process: %+v", err, spec.Process) + } +} + +// procListsEqual is used to check whether 2 Process lists are equal for all +// implemented fields. +func procListsEqual(got, want []*control.Process) bool { + if len(got) != len(want) { + return false + } + for i := range got { + pd1 := got[i] + pd2 := want[i] + // Zero out unimplemented and timing dependant fields. + pd1.Time, pd2.Time = "", "" + pd1.STime, pd2.STime = "", "" + pd1.C, pd2.C = 0, 0 + if *pd1 != *pd2 { + return false + } + } + return true +} + +func procListToString(pl []*control.Process) string { + strs := make([]string, 0, len(pl)) + for _, p := range pl { + strs = append(strs, fmt.Sprintf("%+v", p)) + } + return fmt.Sprintf("[%s]", strings.Join(strs, ",")) +} + +// TestMain acts like runsc if it is called with the "boot" argument, otherwise +// it just runs the tests. This is required because creating a container will +// call "/proc/self/exe boot". Normally /proc/self/exe is the runsc binary, +// but for tests we have to fake it. +func TestMain(m *testing.M) { + // exit writes coverage data before exiting. + exit := func(status int) { + os.Exit(status) + } + + if !flag.Parsed() { + flag.Parse() + } + + // If we are passed one of the commands then run it. + subcommands.Register(new(cmd.Boot), "boot") + subcommands.Register(new(cmd.Gofer), "gofer") + switch flag.Arg(0) { + case "boot", "gofer": + // Run the command in a goroutine so we can block the main + // thread waiting for shutdownSignal. + go func() { + conf := &boot.Config{ + RootDir: "unused-root-dir", + Network: boot.NetworkNone, + } + var ws syscall.WaitStatus + subcmdCode := subcommands.Execute(context.Background(), conf, &ws) + if subcmdCode != subcommands.ExitSuccess { + panic(fmt.Sprintf("command failed to execute, err: %v", subcmdCode)) + } + // Container exited normally. Shut down this process. + os.Exit(ws.ExitStatus()) + }() + + // Shutdown cleanly when the shutdownSignal is received. This + // allows us to write coverage data before exiting. + sigc := make(chan os.Signal, 1) + signal.Notify(sigc, shutdownSignal) + <-sigc + exit(0) + default: + // Otherwise run the tests. + exit(m.Run()) + } +} |