mirror of
https://github.com/genuinetools/reg.git
synced 2024-08-22 06:30:23 -04:00
291 lines
8 KiB
Go
291 lines
8 KiB
Go
![]() |
// +build linux
|
||
|
|
||
|
package libcontainer
|
||
|
|
||
|
import (
|
||
|
"encoding/json"
|
||
|
"fmt"
|
||
|
"os"
|
||
|
"os/exec"
|
||
|
"path/filepath"
|
||
|
"regexp"
|
||
|
"runtime/debug"
|
||
|
"strconv"
|
||
|
"syscall"
|
||
|
|
||
|
"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/systemd"
|
||
|
"github.com/opencontainers/runc/libcontainer/configs"
|
||
|
"github.com/opencontainers/runc/libcontainer/configs/validate"
|
||
|
"github.com/opencontainers/runc/libcontainer/utils"
|
||
|
)
|
||
|
|
||
|
const (
|
||
|
stateFilename = "state.json"
|
||
|
)
|
||
|
|
||
|
var (
|
||
|
idRegex = regexp.MustCompile(`^[\w-\.]+$`)
|
||
|
maxIdLen = 1024
|
||
|
)
|
||
|
|
||
|
// InitArgs returns an options func to configure a LinuxFactory with the
|
||
|
// provided init arguments.
|
||
|
func InitArgs(args ...string) func(*LinuxFactory) error {
|
||
|
return func(l *LinuxFactory) error {
|
||
|
name := args[0]
|
||
|
if filepath.Base(name) == name {
|
||
|
if lp, err := exec.LookPath(name); err == nil {
|
||
|
name = lp
|
||
|
}
|
||
|
} else {
|
||
|
abs, err := filepath.Abs(name)
|
||
|
if err != nil {
|
||
|
return err
|
||
|
}
|
||
|
name = abs
|
||
|
}
|
||
|
l.InitPath = "/proc/self/exe"
|
||
|
l.InitArgs = append([]string{name}, args[1:]...)
|
||
|
return nil
|
||
|
}
|
||
|
}
|
||
|
|
||
|
// InitPath returns an options func to configure a LinuxFactory with the
|
||
|
// provided absolute path to the init binary and arguements.
|
||
|
func InitPath(path string, args ...string) func(*LinuxFactory) error {
|
||
|
return func(l *LinuxFactory) error {
|
||
|
l.InitPath = path
|
||
|
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
|
||
|
}
|
||
|
|
||
|
// 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 := syscall.Mount("tmpfs", l.Root, "tmpfs", 0, ""); err != nil {
|
||
|
return err
|
||
|
}
|
||
|
}
|
||
|
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,
|
||
|
Validator: validate.New(),
|
||
|
CriuPath: "criu",
|
||
|
}
|
||
|
InitArgs(os.Args[0], "init")(l)
|
||
|
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
|
||
|
|
||
|
// InitPath is the absolute path to the init binary.
|
||
|
InitPath 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, 0700); err != nil {
|
||
|
return nil, newGenericError(err, SystemError)
|
||
|
}
|
||
|
c := &linuxContainer{
|
||
|
id: id,
|
||
|
root: containerRoot,
|
||
|
config: config,
|
||
|
initPath: l.InitPath,
|
||
|
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)
|
||
|
if err != nil {
|
||
|
return nil, err
|
||
|
}
|
||
|
r := &nonChildProcess{
|
||
|
processPid: state.InitProcessPid,
|
||
|
processStartTime: state.InitProcessStartTime,
|
||
|
fds: state.ExternalDescriptors,
|
||
|
}
|
||
|
c := &linuxContainer{
|
||
|
initProcess: r,
|
||
|
id: id,
|
||
|
config: &state.Config,
|
||
|
initPath: l.InitPath,
|
||
|
initArgs: l.InitArgs,
|
||
|
criuPath: l.CriuPath,
|
||
|
cgroupManager: l.NewCgroupsManager(state.Config.Cgroups, state.CgroupPaths),
|
||
|
root: containerRoot,
|
||
|
created: state.Created,
|
||
|
}
|
||
|
c.state = &createdState{c: c, s: Created}
|
||
|
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) {
|
||
|
fdStr := os.Getenv("_LIBCONTAINER_INITPIPE")
|
||
|
pipefd, err := strconv.Atoi(fdStr)
|
||
|
if err != nil {
|
||
|
return fmt.Errorf("error converting env var _LIBCONTAINER_INITPIPE(%q) to an int: %s", fdStr, err)
|
||
|
}
|
||
|
var (
|
||
|
pipe = os.NewFile(uintptr(pipefd), "pipe")
|
||
|
it = initType(os.Getenv("_LIBCONTAINER_INITTYPE"))
|
||
|
)
|
||
|
// clear the current process's environment to clean any libcontainer
|
||
|
// specific env vars.
|
||
|
os.Clearenv()
|
||
|
var i initer
|
||
|
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 container's init successed, syscall.Exec will not return, hence
|
||
|
// this defer function will never be called.
|
||
|
if _, ok := i.(*linuxStandardInit); ok {
|
||
|
// Synchronisation only necessary for standard init.
|
||
|
if err := utils.WriteJSON(pipe, syncT{procError}); err != nil {
|
||
|
panic(err)
|
||
|
}
|
||
|
}
|
||
|
if err := utils.WriteJSON(pipe, newSystemError(err)); err != nil {
|
||
|
panic(err)
|
||
|
}
|
||
|
// ensure that this pipe is always closed
|
||
|
pipe.Close()
|
||
|
}()
|
||
|
|
||
|
defer func() {
|
||
|
if e := recover(); e != nil {
|
||
|
err = fmt.Errorf("panic from initialization: %v, %v", e, string(debug.Stack()))
|
||
|
}
|
||
|
}()
|
||
|
|
||
|
i, err = newContainerInit(it, pipe)
|
||
|
if err != nil {
|
||
|
return err
|
||
|
}
|
||
|
return i.Init()
|
||
|
}
|
||
|
|
||
|
func (l *LinuxFactory) loadState(root string) (*State, error) {
|
||
|
f, err := os.Open(filepath.Join(root, stateFilename))
|
||
|
if err != nil {
|
||
|
if os.IsNotExist(err) {
|
||
|
return nil, newGenericError(err, 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)
|
||
|
}
|
||
|
if len(id) > maxIdLen {
|
||
|
return newGenericError(fmt.Errorf("invalid id format: %v", id), InvalidIdFormat)
|
||
|
}
|
||
|
return nil
|
||
|
}
|