aboutsummaryrefslogtreecommitdiff
path: root/vendor/github.com/opencontainers/runc/libcontainer/factory_linux.go
diff options
context:
space:
mode:
Diffstat (limited to 'vendor/github.com/opencontainers/runc/libcontainer/factory_linux.go')
-rw-r--r--vendor/github.com/opencontainers/runc/libcontainer/factory_linux.go325
1 files changed, 325 insertions, 0 deletions
diff --git a/vendor/github.com/opencontainers/runc/libcontainer/factory_linux.go b/vendor/github.com/opencontainers/runc/libcontainer/factory_linux.go
new file mode 100644
index 000000000..42b6f5a05
--- /dev/null
+++ b/vendor/github.com/opencontainers/runc/libcontainer/factory_linux.go
@@ -0,0 +1,325 @@
+// +build linux
+
+package libcontainer
+
+import (
+ "encoding/json"
+ "fmt"
+ "os"
+ "path/filepath"
+ "regexp"
+ "runtime/debug"
+ "strconv"
+
+ "github.com/docker/docker/pkg/mount"
+ "github.com/opencontainers/runc/libcontainer/cgroups"
+ "github.com/opencontainers/runc/libcontainer/cgroups/fs"
+ "github.com/opencontainers/runc/libcontainer/cgroups/rootless"
+ "github.com/opencontainers/runc/libcontainer/cgroups/systemd"
+ "github.com/opencontainers/runc/libcontainer/configs"
+ "github.com/opencontainers/runc/libcontainer/configs/validate"
+ "github.com/opencontainers/runc/libcontainer/utils"
+
+ "golang.org/x/sys/unix"
+)
+
+const (
+ stateFilename = "state.json"
+ execFifoFilename = "exec.fifo"
+)
+
+var idRegex = regexp.MustCompile(`^[\w+-\.]+$`)
+
+// InitArgs returns an options func to configure a LinuxFactory with the
+// provided init binary path and arguments.
+func InitArgs(args ...string) func(*LinuxFactory) error {
+ return func(l *LinuxFactory) (err error) {
+ if len(args) > 0 {
+ // Resolve relative paths to ensure that its available
+ // after directory changes.
+ if args[0], err = filepath.Abs(args[0]); err != nil {
+ return newGenericError(err, ConfigInvalid)
+ }
+ }
+
+ l.InitArgs = args
+ return nil
+ }
+}
+
+// SystemdCgroups is an options func to configure a LinuxFactory to return
+// containers that use systemd to create and manage cgroups.
+func SystemdCgroups(l *LinuxFactory) error {
+ l.NewCgroupsManager = func(config *configs.Cgroup, paths map[string]string) cgroups.Manager {
+ return &systemd.Manager{
+ Cgroups: config,
+ Paths: paths,
+ }
+ }
+ return nil
+}
+
+// Cgroupfs is an options func to configure a LinuxFactory to return
+// containers that use the native cgroups filesystem implementation to
+// create and manage cgroups.
+func Cgroupfs(l *LinuxFactory) error {
+ l.NewCgroupsManager = func(config *configs.Cgroup, paths map[string]string) cgroups.Manager {
+ return &fs.Manager{
+ Cgroups: config,
+ Paths: paths,
+ }
+ }
+ return nil
+}
+
+// RootlessCgroups is an options func to configure a LinuxFactory to
+// return containers that use the "rootless" cgroup manager, which will
+// fail to do any operations not possible to do with an unprivileged user.
+// It should only be used in conjunction with rootless containers.
+func RootlessCgroups(l *LinuxFactory) error {
+ l.NewCgroupsManager = func(config *configs.Cgroup, paths map[string]string) cgroups.Manager {
+ return &rootless.Manager{
+ Cgroups: config,
+ Paths: paths,
+ }
+ }
+ return nil
+}
+
+// TmpfsRoot is an option func to mount LinuxFactory.Root to tmpfs.
+func TmpfsRoot(l *LinuxFactory) error {
+ mounted, err := mount.Mounted(l.Root)
+ if err != nil {
+ return err
+ }
+ if !mounted {
+ if err := unix.Mount("tmpfs", l.Root, "tmpfs", 0, ""); err != nil {
+ return err
+ }
+ }
+ return nil
+}
+
+// CriuPath returns an option func to configure a LinuxFactory with the
+// provided criupath
+func CriuPath(criupath string) func(*LinuxFactory) error {
+ return func(l *LinuxFactory) error {
+ l.CriuPath = criupath
+ return nil
+ }
+}
+
+// New returns a linux based container factory based in the root directory and
+// configures the factory with the provided option funcs.
+func New(root string, options ...func(*LinuxFactory) error) (Factory, error) {
+ if root != "" {
+ if err := os.MkdirAll(root, 0700); err != nil {
+ return nil, newGenericError(err, SystemError)
+ }
+ }
+ l := &LinuxFactory{
+ Root: root,
+ InitArgs: []string{"/proc/self/exe", "init"},
+ Validator: validate.New(),
+ CriuPath: "criu",
+ }
+ Cgroupfs(l)
+ for _, opt := range options {
+ if err := opt(l); err != nil {
+ return nil, err
+ }
+ }
+ return l, nil
+}
+
+// LinuxFactory implements the default factory interface for linux based systems.
+type LinuxFactory struct {
+ // Root directory for the factory to store state.
+ Root string
+
+ // InitArgs are arguments for calling the init responsibilities for spawning
+ // a container.
+ InitArgs []string
+
+ // CriuPath is the path to the criu binary used for checkpoint and restore of
+ // containers.
+ CriuPath string
+
+ // Validator provides validation to container configurations.
+ Validator validate.Validator
+
+ // NewCgroupsManager returns an initialized cgroups manager for a single container.
+ NewCgroupsManager func(config *configs.Cgroup, paths map[string]string) cgroups.Manager
+}
+
+func (l *LinuxFactory) Create(id string, config *configs.Config) (Container, error) {
+ if l.Root == "" {
+ return nil, newGenericError(fmt.Errorf("invalid root"), ConfigInvalid)
+ }
+ if err := l.validateID(id); err != nil {
+ return nil, err
+ }
+ if err := l.Validator.Validate(config); err != nil {
+ return nil, newGenericError(err, ConfigInvalid)
+ }
+ containerRoot := filepath.Join(l.Root, id)
+ if _, err := os.Stat(containerRoot); err == nil {
+ return nil, newGenericError(fmt.Errorf("container with id exists: %v", id), IdInUse)
+ } else if !os.IsNotExist(err) {
+ return nil, newGenericError(err, SystemError)
+ }
+ if err := os.MkdirAll(containerRoot, 0711); err != nil {
+ return nil, newGenericError(err, SystemError)
+ }
+ if err := os.Chown(containerRoot, unix.Geteuid(), unix.Getegid()); err != nil {
+ return nil, newGenericError(err, SystemError)
+ }
+ if config.Rootless {
+ RootlessCgroups(l)
+ }
+ c := &linuxContainer{
+ id: id,
+ root: containerRoot,
+ config: config,
+ initArgs: l.InitArgs,
+ criuPath: l.CriuPath,
+ cgroupManager: l.NewCgroupsManager(config.Cgroups, nil),
+ }
+ c.state = &stoppedState{c: c}
+ return c, nil
+}
+
+func (l *LinuxFactory) Load(id string) (Container, error) {
+ if l.Root == "" {
+ return nil, newGenericError(fmt.Errorf("invalid root"), ConfigInvalid)
+ }
+ containerRoot := filepath.Join(l.Root, id)
+ state, err := l.loadState(containerRoot, id)
+ if err != nil {
+ return nil, err
+ }
+ r := &nonChildProcess{
+ processPid: state.InitProcessPid,
+ processStartTime: state.InitProcessStartTime,
+ fds: state.ExternalDescriptors,
+ }
+ // We have to use the RootlessManager.
+ if state.Rootless {
+ RootlessCgroups(l)
+ }
+ c := &linuxContainer{
+ initProcess: r,
+ initProcessStartTime: state.InitProcessStartTime,
+ id: id,
+ config: &state.Config,
+ initArgs: l.InitArgs,
+ criuPath: l.CriuPath,
+ cgroupManager: l.NewCgroupsManager(state.Config.Cgroups, state.CgroupPaths),
+ root: containerRoot,
+ created: state.Created,
+ }
+ c.state = &loadedState{c: c}
+ if err := c.refreshState(); err != nil {
+ return nil, err
+ }
+ return c, nil
+}
+
+func (l *LinuxFactory) Type() string {
+ return "libcontainer"
+}
+
+// StartInitialization loads a container by opening the pipe fd from the parent to read the configuration and state
+// This is a low level implementation detail of the reexec and should not be consumed externally
+func (l *LinuxFactory) StartInitialization() (err error) {
+ var (
+ pipefd, rootfd int
+ consoleSocket *os.File
+ envInitPipe = os.Getenv("_LIBCONTAINER_INITPIPE")
+ envStateDir = os.Getenv("_LIBCONTAINER_STATEDIR")
+ envConsole = os.Getenv("_LIBCONTAINER_CONSOLE")
+ )
+
+ // Get the INITPIPE.
+ pipefd, err = strconv.Atoi(envInitPipe)
+ if err != nil {
+ return fmt.Errorf("unable to convert _LIBCONTAINER_INITPIPE=%s to int: %s", envInitPipe, err)
+ }
+
+ var (
+ pipe = os.NewFile(uintptr(pipefd), "pipe")
+ it = initType(os.Getenv("_LIBCONTAINER_INITTYPE"))
+ )
+ defer pipe.Close()
+
+ // Only init processes have STATEDIR.
+ rootfd = -1
+ if it == initStandard {
+ if rootfd, err = strconv.Atoi(envStateDir); err != nil {
+ return fmt.Errorf("unable to convert _LIBCONTAINER_STATEDIR=%s to int: %s", envStateDir, err)
+ }
+ }
+
+ if envConsole != "" {
+ console, err := strconv.Atoi(envConsole)
+ if err != nil {
+ return fmt.Errorf("unable to convert _LIBCONTAINER_CONSOLE=%s to int: %s", envConsole, err)
+ }
+ consoleSocket = os.NewFile(uintptr(console), "console-socket")
+ defer consoleSocket.Close()
+ }
+
+ // clear the current process's environment to clean any libcontainer
+ // specific env vars.
+ os.Clearenv()
+
+ defer func() {
+ // We have an error during the initialization of the container's init,
+ // send it back to the parent process in the form of an initError.
+ if werr := utils.WriteJSON(pipe, syncT{procError}); werr != nil {
+ fmt.Fprintln(os.Stderr, err)
+ return
+ }
+ if werr := utils.WriteJSON(pipe, newSystemError(err)); werr != nil {
+ fmt.Fprintln(os.Stderr, err)
+ return
+ }
+ }()
+ defer func() {
+ if e := recover(); e != nil {
+ err = fmt.Errorf("panic from initialization: %v, %v", e, string(debug.Stack()))
+ }
+ }()
+
+ i, err := newContainerInit(it, pipe, consoleSocket, rootfd)
+ if err != nil {
+ return err
+ }
+
+ // If Init succeeds, syscall.Exec will not return, hence none of the defers will be called.
+ return i.Init()
+}
+
+func (l *LinuxFactory) loadState(root, id string) (*State, error) {
+ f, err := os.Open(filepath.Join(root, stateFilename))
+ if err != nil {
+ if os.IsNotExist(err) {
+ return nil, newGenericError(fmt.Errorf("container %q does not exist", id), ContainerNotExists)
+ }
+ return nil, newGenericError(err, SystemError)
+ }
+ defer f.Close()
+ var state *State
+ if err := json.NewDecoder(f).Decode(&state); err != nil {
+ return nil, newGenericError(err, SystemError)
+ }
+ return state, nil
+}
+
+func (l *LinuxFactory) validateID(id string) error {
+ if !idRegex.MatchString(id) {
+ return newGenericError(fmt.Errorf("invalid id format: %v", id), InvalidIdFormat)
+ }
+
+ return nil
+}