// Package daemon exposes the functions that occur on the host server
// that the Docker daemon is running.
//
// In implementing the various functions of the daemon, there is often
// a method-specific struct for configuring the runtime behavior.
package daemon
import (
"errors"
"fmt"
"io"
"io/ioutil"
"net"
"os"
"path"
"path/filepath"
"runtime"
"sync"
"syscall"
"time"
"github.com/Sirupsen/logrus"
"github.com/docker/distribution/digest"
"github.com/docker/docker/api"
"github.com/docker/docker/container"
"github.com/docker/docker/daemon/events"
"github.com/docker/docker/daemon/exec"
"github.com/docker/docker/daemon/execdriver"
"github.com/docker/docker/daemon/execdriver/execdrivers"
"github.com/docker/engine-api/types"
containertypes "github.com/docker/engine-api/types/container"
eventtypes "github.com/docker/engine-api/types/events"
"github.com/docker/engine-api/types/filters"
networktypes "github.com/docker/engine-api/types/network"
registrytypes "github.com/docker/engine-api/types/registry"
"github.com/docker/engine-api/types/strslice"
// register graph drivers
_ "github.com/docker/docker/daemon/graphdriver/register"
"github.com/docker/docker/daemon/logger"
"github.com/docker/docker/daemon/network"
"github.com/docker/docker/distribution"
dmetadata "github.com/docker/docker/distribution/metadata"
"github.com/docker/docker/distribution/xfer"
derr "github.com/docker/docker/errors"
"github.com/docker/docker/image"
"github.com/docker/docker/image/tarexport"
"github.com/docker/docker/layer"
"github.com/docker/docker/migrate/v1"
"github.com/docker/docker/pkg/archive"
"github.com/docker/docker/pkg/fileutils"
"github.com/docker/docker/pkg/graphdb"
"github.com/docker/docker/pkg/idtools"
"github.com/docker/docker/pkg/mount"
"github.com/docker/docker/pkg/namesgenerator"
"github.com/docker/docker/pkg/progress"
"github.com/docker/docker/pkg/registrar"
"github.com/docker/docker/pkg/signal"
"github.com/docker/docker/pkg/streamformatter"
"github.com/docker/docker/pkg/stringid"
"github.com/docker/docker/pkg/sysinfo"
"github.com/docker/docker/pkg/system"
"github.com/docker/docker/pkg/truncindex"
"github.com/docker/docker/reference"
"github.com/docker/docker/registry"
"github.com/docker/docker/runconfig"
"github.com/docker/docker/utils"
volumedrivers "github.com/docker/docker/volume/drivers"
"github.com/docker/docker/volume/local"
"github.com/docker/docker/volume/store"
"github.com/docker/go-connections/nat"
"github.com/docker/libnetwork"
lntypes "github.com/docker/libnetwork/types"
"github.com/docker/libtrust"
"github.com/opencontainers/runc/libcontainer"
"golang.org/x/net/context"
)
const (
// maxDownloadConcurrency is the maximum number of downloads that
// may take place at a time for each pull.
maxDownloadConcurrency = 3
// maxUploadConcurrency is the maximum number of uploads that
// may take place at a time for each push.
maxUploadConcurrency = 5
)
var (
validContainerNameChars = utils.RestrictedNameChars
validContainerNamePattern = utils.RestrictedNamePattern
errSystemNotSupported = errors.New("The Docker daemon is not supported on this platform.")
)
// ErrImageDoesNotExist is error returned when no image can be found for a reference.
type ErrImageDoesNotExist struct {
RefOrID string
}
func (e ErrImageDoesNotExist) Error() string {
return fmt.Sprintf("no such id: %s", e.RefOrID)
}
// Daemon holds information about the Docker daemon.
type Daemon struct {
ID string
repository string
containers container.Store
execCommands *exec.Store
referenceStore reference.Store
downloadManager *xfer.LayerDownloadManager
uploadManager *xfer.LayerUploadManager
distributionMetadataStore dmetadata.Store
trustKey libtrust.PrivateKey
idIndex *truncindex.TruncIndex
configStore *Config
execDriver execdriver.Driver
statsCollector *statsCollector
defaultLogConfig containertypes.LogConfig
RegistryService *registry.Service
EventsService *events.Events
netController libnetwork.NetworkController
volumes *store.VolumeStore
discoveryWatcher discoveryReloader
root string
seccompEnabled bool
shutdown bool
uidMaps []idtools.IDMap
gidMaps []idtools.IDMap
layerStore layer.Store
imageStore image.Store
nameIndex *registrar.Registrar
linkIndex *linkIndex
}
// GetContainer looks for a container using the provided information, which could be
// one of the following inputs from the caller:
// - A full container ID, which will exact match a container in daemon's list
// - A container name, which will only exact match via the GetByName() function
// - A partial container ID prefix (e.g. short ID) of any length that is
// unique enough to only return a single container object
// If none of these searches succeed, an error is returned
func (daemon *Daemon) GetContainer(prefixOrName string) (*container.Container, error) {
if containerByID := daemon.containers.Get(prefixOrName); containerByID != nil {
// prefix is an exact match to a full container ID
return containerByID, nil
}
// GetByName will match only an exact name provided; we ignore errors
if containerByName, _ := daemon.GetByName(prefixOrName); containerByName != nil {
// prefix is an exact match to a full container Name
return containerByName, nil
}
containerID, indexError := daemon.idIndex.Get(prefixOrName)
if indexError != nil {
// When truncindex defines an error type, use that instead
if indexError == truncindex.ErrNotExist {
return nil, derr.ErrorCodeNoSuchContainer.WithArgs(prefixOrName)
}
return nil, indexError
}
return daemon.containers.Get(containerID), nil
}
// Exists returns a true if a container of the specified ID or name exists,
// false otherwise.
func (daemon *Daemon) Exists(id string) bool {
c, _ := daemon.GetContainer(id)
return c != nil
}
// IsPaused returns a bool indicating if the specified container is paused.
func (daemon *Daemon) IsPaused(id string) bool {
c, _ := daemon.GetContainer(id)
return c.State.IsPaused()
}
func (daemon *Daemon) containerRoot(id string) string {
return filepath.Join(daemon.repository, id)
}
// Load reads the contents of a container from disk
// This is typically done at startup.
func (daemon *Daemon) load(id string) (*container.Container, error) {
container := daemon.newBaseContainer(id)
if err := container.FromDisk(); err != nil {
return nil, err
}
if container.ID != id {
return container, fmt.Errorf("Container %s is stored at %s", container.ID, id)
}
return container, nil
}
func (daemon *Daemon) registerName(container *container.Container) error {
if daemon.Exists(container.ID) {
return fmt.Errorf("Container is already loaded")
}
if err := validateID(container.ID); err != nil {
return err
}
if container.Name == "" {
name, err := daemon.generateNewName(container.ID)
if err != nil {
return err
}
container.Name = name
if err := container.ToDiskLocking(); err != nil {
logrus.Errorf("Error saving container name to disk: %v", err)
}
}
return daemon.nameIndex.Reserve(container.Name, container.ID)
}
// Register makes a container object usable by the daemon as <container.ID>
func (daemon *Daemon) Register(container *container.Container) error {
// Attach to stdout and stderr
if container.Config.OpenStdin {
container.NewInputPipes()
} else {
container.NewNopInputPipe()
}
daemon.containers.Add(container.ID, container)
daemon.idIndex.Add(container.ID)
if container.IsRunning() {
logrus.Debugf("killing old running container %s", container.ID)
// Set exit code to 128 + SIGKILL (9) to properly represent unsuccessful exit
container.SetStoppedLocking(&execdriver.ExitStatus{ExitCode: 137})
// use the current driver and ensure that the container is dead x.x
cmd := &execdriver.Command{
CommonCommand: execdriver.CommonCommand{
ID: container.ID,
},
}
daemon.execDriver.Terminate(cmd)
container.UnmountIpcMounts(mount.Unmount)
daemon.Unmount(container)
if err := container.ToDiskLocking(); err != nil {
logrus.Errorf("Error saving stopped state to disk: %v", err)
}
}
return nil
}
func (daemon *Daemon) restore() error {
var (
debug = utils.IsDebugEnabled()
currentDriver = daemon.GraphDriverName()
containers = make(map[string]*container.Container)
)
if !debug {
logrus.Info("Loading containers: start.")
}
dir, err := ioutil.ReadDir(daemon.repository)
if err != nil {
return err
}
for _, v := range dir {
id := v.Name()
container, err := daemon.load(id)
if !debug && logrus.GetLevel() == logrus.InfoLevel {
fmt.Print(".")
}
if err != nil {
logrus.Errorf("Failed to load container %v: %v", id, err)
continue
}
rwlayer, err := daemon.layerStore.GetRWLayer(container.ID)
if err != nil {
logrus.Errorf("Failed to load container mount %v: %v", id, err)
continue
}
container.RWLayer = rwlayer
// Ignore the container if it does not support the current driver being used by the graph
if (container.Driver == "" && currentDriver == "aufs") || container.Driver == currentDriver {
logrus.Debugf("Loaded container %v", container.ID)
containers[container.ID] = container
} else {
logrus.Debugf("Cannot load container %s because it was created with another graph driver.", container.ID)
}
}
var migrateLegacyLinks bool
restartContainers := make(map[*container.Container]chan struct{})
for _, c := range containers {
if err := daemon.registerName(c); err != nil {
logrus.Errorf("Failed to register container %s: %s", c.ID, err)
continue
}
if err := daemon.Register(c); err != nil {
logrus.Errorf("Failed to register container %s: %s", c.ID, err)
continue
}
// get list of containers we need to restart
if daemon.configStore.AutoRestart && c.ShouldRestart() {
restartContainers[c] = make(chan struct{})
}
// if c.hostConfig.Links is nil (not just empty), then it is using the old sqlite links and needs to be migrated
if c.HostConfig != nil && c.HostConfig.Links == nil {
migrateLegacyLinks = true
}
}
// migrate any legacy links from sqlite
linkdbFile := filepath.Join(daemon.root, "linkgraph.db")
var legacyLinkDB *graphdb.Database
if migrateLegacyLinks {
legacyLinkDB, err = graphdb.NewSqliteConn(linkdbFile)
if err != nil {
return fmt.Errorf("error connecting to legacy link graph DB %s, container links may be lost: %v", linkdbFile, err)
}
defer legacyLinkDB.Close()
}
// Now that all the containers are registered, register the links
for _, c := range containers {
if migrateLegacyLinks {
if err := daemon.migrateLegacySqliteLinks(legacyLinkDB, c); err != nil {
return err
}
}
if err := daemon.registerLinks(c, c.HostConfig); err != nil {
logrus.Errorf("failed to register link for container %s: %v", c.ID, err)
}
}
group := sync.WaitGroup{}
for c, notifier := range restartContainers {
group.Add(1)
go func(c *container.Container, chNotify chan struct{}) {
defer group.Done()
logrus.Debugf("Starting container %s", c.ID)
// ignore errors here as this is a best effort to wait for children to be
// running before we try to start the container
children := daemon.children(c)
timeout := time.After(5 * time.Second)
for _, child := range children {
if notifier, exists := restartContainers[child]; exists {
select {
case <-notifier:
case <-timeout:
}
}
}
if err := daemon.containerStart(c); err != nil {
logrus.Errorf("Failed to start container %s: %s", c.ID, err)
}
close(chNotify)
}(c, notifier)
}
group.Wait()
// any containers that were started above would already have had this done,
// however we need to now prepare the mountpoints for the rest of the containers as well.
// This shouldn't cause any issue running on the containers that already had this run.
// This must be run after any containers with a restart policy so that containerized plugins
// can have a chance to be running before we try to initialize them.
for _, c := range containers {
group.Add(1)
go func(c *container.Container) {
defer group.Done()
if err := daemon.prepareMountPoints(c); err != nil {
logrus.Error(err)
}
}(c)
}
group.Wait()
if !debug {
if logrus.GetLevel() == logrus.InfoLevel {
fmt.Println()
}
logrus.Info("Loading containers: done.")
}
return nil
}
func (daemon *Daemon) mergeAndVerifyConfig(config *containertypes.Config, img *image.Image) error {
if img != nil && img.Config != nil {
if err := merge(config, img.Config); err != nil {
return err
}
}
if config.Entrypoint.Len() == 0 && config.Cmd.Len() == 0 {
return fmt.Errorf("No command specified")
}
return nil
}
func (daemon *Daemon) generateIDAndName(name string) (string, string, error) {
var (
err error
id = stringid.GenerateNonCryptoID()
)
if name == "" {
if name, err = daemon.generateNewName(id); err != nil {
return "", "", err
}
return id, name, nil
}
if name, err = daemon.reserveName(id, name); err != nil {
return "", "", err
}
return id, name, nil
}
func (daemon *Daemon) reserveName(id, name string) (string, error) {
if !validContainerNamePattern.MatchString(name) {
return "", fmt.Errorf("Invalid container name (%s), only %s are allowed", name, validContainerNameChars)
}
if name[0] != '/' {
name = "/" + name
}
if err := daemon.nameIndex.Reserve(name, id); err != nil {
if err == registrar.ErrNameReserved {
id, err := daemon.nameIndex.Get(name)
if err != nil {
logrus.Errorf("got unexpected error while looking up reserved name: %v", err)
return "", err
}
return "", fmt.Errorf("Conflict. The name %q is already in use by container %s. You have to remove (or rename) that container to be able to reuse that name.", name, id)
}
return "", fmt.Errorf("error reserving name: %s, error: %v", name, err)
}
return name, nil
}
func (daemon *Daemon) releaseName(name string) {
daemon.nameIndex.Release(name)
}
func (daemon *Daemon) generateNewName(id string) (string, error) {
var name string
for i := 0; i < 6; i++ {
name = namesgenerator.GetRandomName(i)
if name[0] != '/' {
name = "/" + name
}
if err := daemon.nameIndex.Reserve(name, id); err != nil {
if err == registrar.ErrNameReserved {
continue
}
return "", err
}
return name, nil
}
name = "/" + stringid.TruncateID(id)
if err := daemon.nameIndex.Reserve(name, id); err != nil {
return "", err
}
return name, nil
}
func (daemon *Daemon) generateHostname(id string, config *containertypes.Config) {
// Generate default hostname
if config.Hostname == "" {
config.Hostname = id[:12]
}
}
func (daemon *Daemon) getEntrypointAndArgs(configEntrypoint *strslice.StrSlice, configCmd *strslice.StrSlice) (string, []string) {
cmdSlice := configCmd.Slice()
if configEntrypoint.Len() != 0 {
eSlice := configEntrypoint.Slice()
return eSlice[0], append(eSlice[1:], cmdSlice...)
}
return cmdSlice[0], cmdSlice[1:]
}
func (daemon *Daemon) newContainer(name string, config *containertypes.Config, imgID image.ID) (*container.Container, error) {
var (
id string
err error
noExplicitName = name == ""
)
id, name, err = daemon.generateIDAndName(name)
if err != nil {
return nil, err
}
daemon.generateHostname(id, config)
entrypoint, args := daemon.getEntrypointAndArgs(config.Entrypoint, config.Cmd)
base := daemon.newBaseContainer(id)
base.Created = time.Now().UTC()
base.Path = entrypoint
base.Args = args //FIXME: de-duplicate from config
base.Config = config
base.HostConfig = &containertypes.HostConfig{}
base.ImageID = imgID
base.NetworkSettings = &network.Settings{IsAnonymousEndpoint: noExplicitName}
base.Name = name
base.Driver = daemon.GraphDriverName()
return base, err
}
// GetByName returns a container given a name.
func (daemon *Daemon) GetByName(name string) (*container.Container, error) {
fullName := name
if name[0] != '/' {
fullName = "/" + name
}
id, err := daemon.nameIndex.Get(fullName)
if err != nil {
return nil, fmt.Errorf("Could not find entity for %s", name)
}
e := daemon.containers.Get(id)
if e == nil {
return nil, fmt.Errorf("Could not find container for entity id %s", id)
}
return e, nil
}
// SubscribeToEvents returns the currently record of events, a channel to stream new events from, and a function to cancel the stream of events.
func (daemon *Daemon) SubscribeToEvents(since, sinceNano int64, filter filters.Args) ([]eventtypes.Message, chan interface{}) {
ef := events.NewFilter(filter)
return daemon.EventsService.SubscribeTopic(since, sinceNano, ef)
}
// UnsubscribeFromEvents stops the event subscription for a client by closing the
// channel where the daemon sends events to.
func (daemon *Daemon) UnsubscribeFromEvents(listener chan interface{}) {
daemon.EventsService.Evict(listener)
}
// GetLabels for a container or image id
func (daemon *Daemon) GetLabels(id string) map[string]string {
// TODO: TestCase
container := daemon.containers.Get(id)
if container != nil {
return container.Config.Labels
}
img, err := daemon.GetImage(id)
if err == nil {
return img.ContainerConfig.Labels
}
return nil
}
func (daemon *Daemon) children(c *container.Container) map[string]*container.Container {
return daemon.linkIndex.children(c)
}
// parents returns the names of the parent containers of the container
// with the given name.
func (daemon *Daemon) parents(c *container.Container) map[string]*container.Container {
return daemon.linkIndex.parents(c)
}
func (daemon *Daemon) registerLink(parent, child *container.Container, alias string) error {
fullName := path.Join(parent.Name, alias)
if err := daemon.nameIndex.Reserve(fullName, child.ID); err != nil {
if err == registrar.ErrNameReserved {
logrus.Warnf("error registering link for %s, to %s, as alias %s, ignoring: %v", parent.ID, child.ID, alias, err)
return nil
}
return err
}
daemon.linkIndex.link(parent, child, fullName)
return nil
}
// NewDaemon sets up everything for the daemon to be able to service
// requests from the webserver.
func NewDaemon(config *Config, registryService *registry.Service) (daemon *Daemon, err error) {
setDefaultMtu(config)
// Ensure we have compatible and valid configuration options
if err := verifyDaemonSettings(config); err != nil {
return nil, err
}
// Do we have a disabled network?
config.DisableBridge = isBridgeNetworkDisabled(config)
// Verify the platform is supported as a daemon
if !platformSupported {
return nil, errSystemNotSupported
}
// Validate platform-specific requirements
if err := checkSystem(); err != nil {
return nil, err
}
// set up SIGUSR1 handler on Unix-like systems, or a Win32 global event
// on Windows to dump Go routine stacks
setupDumpStackTrap()
uidMaps, gidMaps, err := setupRemappedRoot(config)
if err != nil {
return nil, err
}
rootUID, rootGID, err := idtools.GetRootUIDGID(uidMaps, gidMaps)
if err != nil {
return nil, err
}
// get the canonical path to the Docker root directory
var realRoot string
if _, err := os.Stat(config.Root); err != nil && os.IsNotExist(err) {
realRoot = config.Root
} else {
realRoot, err = fileutils.ReadSymlinkedDirectory(config.Root)
if err != nil {
return nil, fmt.Errorf("Unable to get the full path to root (%s): %s", config.Root, err)
}
}
if err = setupDaemonRoot(config, realRoot, rootUID, rootGID); err != nil {
return nil, err
}
// set up the tmpDir to use a canonical path
tmp, err := tempDir(config.Root, rootUID, rootGID)
if err != nil {
return nil, fmt.Errorf("Unable to get the TempDir under %s: %s", config.Root, err)
}
realTmp, err := fileutils.ReadSymlinkedDirectory(tmp)
if err != nil {
return nil, fmt.Errorf("Unable to get the full path to the TempDir (%s): %s", tmp, err)
}
os.Setenv("TMPDIR", realTmp)
d := &Daemon{}
// Ensure the daemon is properly shutdown if there is a failure during
// initialization
defer func() {
if err != nil {
if err := d.Shutdown(); err != nil {
logrus.Error(err)
}
}
}()
// Verify logging driver type
if config.LogConfig.Type != "none" {
if _, err := logger.GetLogDriver(config.LogConfig.Type); err != nil {
return nil, fmt.Errorf("error finding the logging driver: %v", err)
}
}
logrus.Debugf("Using default logging driver %s", config.LogConfig.Type)
daemonRepo := filepath.Join(config.Root, "containers")
if err := idtools.MkdirAllAs(daemonRepo, 0700, rootUID, rootGID); err != nil && !os.IsExist(err) {
return nil, err
}
driverName := os.Getenv("DOCKER_DRIVER")
if driverName == "" {
driverName = config.GraphDriver
}
d.layerStore, err = layer.NewStoreFromOptions(layer.StoreOptions{
StorePath: config.Root,
MetadataStorePathTemplate: filepath.Join(config.Root, "image", "%s", "layerdb"),
GraphDriver: driverName,
GraphDriverOptions: config.GraphOptions,
UIDMaps: uidMaps,
GIDMaps: gidMaps,
})
if err != nil {
return nil, err
}
graphDriver := d.layerStore.DriverName()
imageRoot := filepath.Join(config.Root, "image", graphDriver)
// Configure and validate the kernels security support
if err := configureKernelSecuritySupport(config, graphDriver); err != nil {
return nil, err
}
d.downloadManager = xfer.NewLayerDownloadManager(d.layerStore, maxDownloadConcurrency)
d.uploadManager = xfer.NewLayerUploadManager(maxUploadConcurrency)
ifs, err := image.NewFSStoreBackend(filepath.Join(imageRoot, "imagedb"))
if err != nil {
return nil, err
}
d.imageStore, err = image.NewImageStore(ifs, d.layerStore)
if err != nil {
return nil, err
}
// Configure the volumes driver
volStore, err := configureVolumes(config, rootUID, rootGID)
if err != nil {
return nil, err
}
trustKey, err := api.LoadOrCreateTrustKey(config.TrustKeyPath)
if err != nil {
return nil, err
}
trustDir := filepath.Join(config.Root, "trust")
if err := system.MkdirAll(trustDir, 0700); err != nil {
return nil, err
}
distributionMetadataStore, err := dmetadata.NewFSMetadataStore(filepath.Join(imageRoot, "distribution"))
if err != nil {
return nil, err
}
eventsService := events.New()
referenceStore, err := reference.NewReferenceStore(filepath.Join(imageRoot, "repositories.json"))
if err != nil {
return nil, fmt.Errorf("Couldn't create Tag store repositories: %s", err)
}
if err := restoreCustomImage(d.imageStore, d.layerStore, referenceStore); err != nil {
return nil, fmt.Errorf("Couldn't restore custom images: %s", err)
}
migrationStart := time.Now()
if err := v1.Migrate(config.Root, graphDriver, d.layerStore, d.imageStore, referenceStore, distributionMetadataStore); err != nil {
logrus.Errorf("Graph migration failed: %q. Your old graph data was found to be too inconsistent for upgrading to content-addressable storage. Some of the old data was probably not upgraded. We recommend starting over with a clean storage directory if possible.", err)
}
logrus.Infof("Graph migration to content-addressability took %.2f seconds", time.Since(migrationStart).Seconds())
// Discovery is only enabled when the daemon is launched with an address to advertise. When
// initialized, the daemon is registered and we can store the discovery backend as its read-only
if err := d.initDiscovery(config); err != nil {
return nil, err
}
d.netController, err = d.initNetworkController(config)
if err != nil {
return nil, fmt.Errorf("Error initializing network controller: %v", err)
}
sysInfo := sysinfo.New(false)
// Check if Devices cgroup is mounted, it is hard requirement for container security,
// on Linux/FreeBSD.
if runtime.GOOS != "windows" && !sysInfo.CgroupDevicesEnabled {
return nil, fmt.Errorf("Devices cgroup isn't mounted")
}
ed, err := execdrivers.NewDriver(config.ExecOptions, config.ExecRoot, config.Root, sysInfo)
if err != nil {
return nil, err
}
d.ID = trustKey.PublicKey().KeyID()
d.repository = daemonRepo
d.containers = container.NewMemoryStore()
d.execCommands = exec.NewStore()
d.referenceStore = referenceStore
d.distributionMetadataStore = distributionMetadataStore
d.trustKey = trustKey
d.idIndex = truncindex.NewTruncIndex([]string{})
d.configStore = config
d.execDriver = ed
d.statsCollector = d.newStatsCollector(1 * time.Second)
d.defaultLogConfig = containertypes.LogConfig{
Type: config.LogConfig.Type,
Config: config.LogConfig.Config,
}
d.RegistryService = registryService
d.EventsService = eventsService
d.volumes = volStore
d.root = config.Root
d.uidMaps = uidMaps
d.gidMaps = gidMaps
d.seccompEnabled = sysInfo.Seccomp
d.nameIndex = registrar.NewRegistrar()
d.linkIndex = newLinkIndex()
if err := d.cleanupMounts(); err != nil {
return nil, err
}
go d.execCommandGC()
if err := d.restore(); err != nil {
return nil, err
}
return d, nil
}
func (daemon *Daemon) shutdownContainer(c *container.Container) error {
// TODO(windows): Handle docker restart with paused containers
if c.IsPaused() {
// To terminate a process in freezer cgroup, we should send
// SIGTERM to this process then unfreeze it, and the process will
// force to terminate immediately.
logrus.Debugf("Found container %s is paused, sending SIGTERM before unpause it", c.ID)
sig, ok := signal.SignalMap["TERM"]
if !ok {
return fmt.Errorf("System doesn not support SIGTERM")
}
if err := daemon.kill(c, int(sig)); err != nil {
return fmt.Errorf("sending SIGTERM to container %s with error: %v", c.ID, err)
}
if err := daemon.containerUnpause(c); err != nil {
return fmt.Errorf("Failed to unpause container %s with error: %v", c.ID, err)
}
if _, err := c.WaitStop(10 * time.Second); err != nil {
logrus.Debugf("container %s failed to exit in 10 second of SIGTERM, sending SIGKILL to force", c.ID)
sig, ok := signal.SignalMap["KILL"]
if !ok {
return fmt.Errorf("System does not support SIGKILL")
}
if err := daemon.kill(c, int(sig)); err != nil {
logrus.Errorf("Failed to SIGKILL container %s", c.ID)
}
c.WaitStop(-1 * time.Second)
return err
}
}
// If container failed to exit in 10 seconds of SIGTERM, then using the force
if err := daemon.containerStop(c, 10); err != nil {
return fmt.Errorf("Stop container %s with error: %v", c.ID, err)
}
c.WaitStop(-1 * time.Second)
return nil
}
// Shutdown stops the daemon.
func (daemon *Daemon) Shutdown() error {
daemon.shutdown = true
if daemon.containers != nil {
logrus.Debug("starting clean shutdown of all containers...")
daemon.containers.ApplyAll(func(c *container.Container) {
if !c.IsRunning() {
return
}
logrus.Debugf("stopping %s", c.ID)
if err := daemon.shutdownContainer(c); err != nil {
logrus.Errorf("Stop container error: %v", err)
return
}
logrus.Debugf("container stopped %s", c.ID)
})
}
// trigger libnetwork Stop only if it's initialized
if daemon.netController != nil {
daemon.netController.Stop()
}
if daemon.layerStore != nil {
if err := daemon.layerStore.Cleanup(); err != nil {
logrus.Errorf("Error during layer Store.Cleanup(): %v", err)
}
}
if err := daemon.cleanupMounts(); err != nil {
return err
}
return nil
}
// Mount sets container.BaseFS
// (is it not set coming in? why is it unset?)
func (daemon *Daemon) Mount(container *container.Container) error {
dir, err := container.RWLayer.Mount(container.GetMountLabel())
if err != nil {
return err
}
logrus.Debugf("container mounted via layerStore: %v", dir)
if container.BaseFS != dir {
// The mount path reported by the graph driver should always be trusted on Windows, since the
// volume path for a given mounted layer may change over time. This should only be an error
// on non-Windows operating systems.
if container.BaseFS != "" && runtime.GOOS != "windows" {
daemon.Unmount(container)
return fmt.Errorf("Error: driver %s is returning inconsistent paths for container %s ('%s' then '%s')",
daemon.GraphDriverName(), container.ID, container.BaseFS, dir)
}
}
container.BaseFS = dir // TODO: combine these fields
return nil
}
// Unmount unsets the container base filesystem
func (daemon *Daemon) Unmount(container *container.Container) {
if err := container.RWLayer.Unmount(); err != nil {
logrus.Errorf("Error unmounting container %s: %s", container.ID, err)
}
}
// Run uses the execution driver to run a given container
func (daemon *Daemon) Run(c *container.Container, pipes *execdriver.Pipes, startCallback execdriver.DriverCallback) (execdriver.ExitStatus, error) {
hooks := execdriver.Hooks{
Start: startCallback,
}
hooks.PreStart = append(hooks.PreStart, func(processConfig *execdriver.ProcessConfig, pid int, chOOM <-chan struct{}) error {
return daemon.setNetworkNamespaceKey(c.ID, pid)
})
return daemon.execDriver.Run(c.Command, pipes, hooks)
}
func (daemon *Daemon) kill(c *container.Container, sig int) error {
return daemon.execDriver.Kill(c.Command, sig)
}
func (daemon *Daemon) stats(c *container.Container) (*execdriver.ResourceStats, error) {
return daemon.execDriver.Stats(c.ID)
}
func (daemon *Daemon) subscribeToContainerStats(c *container.Container) chan interface{} {
return daemon.statsCollector.collect(c)
}
func (daemon *Daemon) unsubscribeToContainerStats(c *container.Container, ch chan interface{}) {
daemon.statsCollector.unsubscribe(c, ch)
}
func (daemon *Daemon) changes(container *container.Container) ([]archive.Change, error) {
return container.RWLayer.Changes()
}
// TagImage creates a tag in the repository reponame, pointing to the image named
// imageName.
func (daemon *Daemon) TagImage(newTag reference.Named, imageName string) error {
imageID, err := daemon.GetImageID(imageName)
if err != nil {
return err
}
if err := daemon.referenceStore.AddTag(newTag, imageID, true); err != nil {
return err
}
daemon.LogImageEvent(imageID.String(), newTag.String(), "tag")
return nil
}
func writeDistributionProgress(cancelFunc func(), outStream io.Writer, progressChan <-chan progress.Progress) {
progressOutput := streamformatter.NewJSONStreamFormatter().NewProgressOutput(outStream, false)
operationCancelled := false
for prog := range progressChan {
if err := progressOutput.WriteProgress(prog); err != nil && !operationCancelled {
// don't log broken pipe errors as this is the normal case when a client aborts
if isBrokenPipe(err) {
logrus.Info("Pull session cancelled")
} else {
logrus.Errorf("error writing progress to client: %v", err)
}
cancelFunc()
operationCancelled = true
// Don't return, because we need to continue draining
// progressChan until it's closed to avoid a deadlock.
}
}
}
func isBrokenPipe(e error) bool {
if netErr, ok := e.(*net.OpError); ok {
e = netErr.Err
if sysErr, ok := netErr.Err.(*os.SyscallError); ok {
e = sysErr.Err
}
}
return e == syscall.EPIPE
}
// PullImage initiates a pull operation. image is the repository name to pull, and
// tag may be either empty, or indicate a specific tag to pull.
func (daemon *Daemon) PullImage(ref reference.Named, metaHeaders map[string][]string, authConfig *types.AuthConfig, outStream io.Writer) error {
// Include a buffer so that slow client connections don't affect
// transfer performance.
progressChan := make(chan progress.Progress, 100)
writesDone := make(chan struct{})
ctx, cancelFunc := context.WithCancel(context.Background())
go func() {
writeDistributionProgress(cancelFunc, outStream, progressChan)
close(writesDone)
}()
imagePullConfig := &distribution.ImagePullConfig{
MetaHeaders: metaHeaders,
AuthConfig: authConfig,
ProgressOutput: progress.ChanOutput(progressChan),
RegistryService: daemon.RegistryService,
ImageEventLogger: daemon.LogImageEvent,
MetadataStore: daemon.distributionMetadataStore,
ImageStore: daemon.imageStore,
ReferenceStore: daemon.referenceStore,
DownloadManager: daemon.downloadManager,
}
err := distribution.Pull(ctx, ref, imagePullConfig)
close(progressChan)
<-writesDone
return err
}
// ExportImage exports a list of images to the given output stream. The
// exported images are archived into a tar when written to the output
// stream. All images with the given tag and all versions containing
// the same tag are exported. names is the set of tags to export, and
// outStream is the writer which the images are written to.
func (daemon *Daemon) ExportImage(names []string, outStream io.Writer) error {
imageExporter := tarexport.NewTarExporter(daemon.imageStore, daemon.layerStore, daemon.referenceStore)
return imageExporter.Save(names, outStream)
}
// PushImage initiates a push operation on the repository named localName.
func (daemon *Daemon) PushImage(ref reference.Named, metaHeaders map[string][]string, authConfig *types.AuthConfig, outStream io.Writer) error {
// Include a buffer so that slow client connections don't affect
// transfer performance.
progressChan := make(chan progress.Progress, 100)
writesDone := make(chan struct{})
ctx, cancelFunc := context.WithCancel(context.Background())
go func() {
writeDistributionProgress(cancelFunc, outStream, progressChan)
close(writesDone)
}()
imagePushConfig := &distribution.ImagePushConfig{
MetaHeaders: metaHeaders,
AuthConfig: authConfig,
ProgressOutput: progress.ChanOutput(progressChan),
RegistryService: daemon.RegistryService,
ImageEventLogger: daemon.LogImageEvent,
MetadataStore: daemon.distributionMetadataStore,
LayerStore: daemon.layerStore,
ImageStore: daemon.imageStore,
ReferenceStore: daemon.referenceStore,
TrustKey: daemon.trustKey,
UploadManager: daemon.uploadManager,
}
err := distribution.Push(ctx, ref, imagePushConfig)
close(progressChan)
<-writesDone
return err
}
// LookupImage looks up an image by name and returns it as an ImageInspect
// structure.
func (daemon *Daemon) LookupImage(name string) (*types.ImageInspect, error) {
img, err := daemon.GetImage(name)
if err != nil {
return nil, fmt.Errorf("No such image: %s", name)
}
refs := daemon.referenceStore.References(img.ID())
repoTags := []string{}
repoDigests := []string{}
for _, ref := range refs {
switch ref.(type) {
case reference.NamedTagged:
repoTags = append(repoTags, ref.String())
case reference.Canonical:
repoDigests = append(repoDigests, ref.String())
}
}
var size int64
var layerMetadata map[string]string
layerID := img.RootFS.ChainID()
if layerID != "" {
l, err := daemon.layerStore.Get(layerID)
if err != nil {
return nil, err
}
defer layer.ReleaseAndLog(daemon.layerStore, l)
size, err = l.Size()
if err != nil {
return nil, err
}
layerMetadata, err = l.Metadata()
if err != nil {
return nil, err
}
}
comment := img.Comment
if len(comment) == 0 && len(img.History) > 0 {
comment = img.History[len(img.History)-1].Comment
}
imageInspect := &types.ImageInspect{
ID: img.ID().String(),
RepoTags: repoTags,
RepoDigests: repoDigests,
Parent: img.Parent.String(),
Comment: comment,
Created: img.Created.Format(time.RFC3339Nano),
Container: img.Container,
ContainerConfig: &img.ContainerConfig,
DockerVersion: img.DockerVersion,
Author: img.Author,
Config: img.Config,
Architecture: img.Architecture,
Os: img.OS,
Size: size,
VirtualSize: size, // TODO: field unused, deprecate
}
imageInspect.GraphDriver.Name = daemon.GraphDriverName()
imageInspect.GraphDriver.Data = layerMetadata
return imageInspect, nil
}
// LoadImage uploads a set of images into the repository. This is the
// complement of ImageExport. The input stream is an uncompressed tar
// ball containing images and metadata.
func (daemon *Daemon) LoadImage(inTar io.ReadCloser, outStream io.Writer) error {
imageExporter := tarexport.NewTarExporter(daemon.imageStore, daemon.layerStore, daemon.referenceStore)
return imageExporter.Load(inTar, outStream)
}
// ImageHistory returns a slice of ImageHistory structures for the specified image
// name by walking the image lineage.
func (daemon *Daemon) ImageHistory(name string) ([]*types.ImageHistory, error) {
img, err := daemon.GetImage(name)
if err != nil {
return nil, err
}
history := []*types.ImageHistory{}
layerCounter := 0
rootFS := *img.RootFS
rootFS.DiffIDs = nil
for _, h := range img.History {
var layerSize int64
if !h.EmptyLayer {
if len(img.RootFS.DiffIDs) <= layerCounter {
return nil, errors.New("too many non-empty layers in History section")
}
rootFS.Append(img.RootFS.DiffIDs[layerCounter])
l, err := daemon.layerStore.Get(rootFS.ChainID())
if err != nil {
return nil, err
}
layerSize, err = l.DiffSize()
layer.ReleaseAndLog(daemon.layerStore, l)
if err != nil {
return nil, err
}
layerCounter++
}
history = append([]*types.ImageHistory{{
ID: "<missing>",
Created: h.Created.Unix(),
CreatedBy: h.CreatedBy,
Comment: h.Comment,
Size: layerSize,
}}, history...)
}
// Fill in image IDs and tags
histImg := img
id := img.ID()
for _, h := range history {
h.ID = id.String()
var tags []string
for _, r := range daemon.referenceStore.References(id) {
if _, ok := r.(reference.NamedTagged); ok {
tags = append(tags, r.String())
}
}
h.Tags = tags
id = histImg.Parent
if id == "" {
break
}
histImg, err = daemon.GetImage(id.String())
if err != nil {
break
}
}
return history, nil
}
// GetImageID returns an image ID corresponding to the image referred to by
// refOrID.
func (daemon *Daemon) GetImageID(refOrID string) (image.ID, error) {
// Treat as an ID
if id, err := digest.ParseDigest(refOrID); err == nil {
if _, err := daemon.imageStore.Get(image.ID(id)); err != nil {
return "", ErrImageDoesNotExist{refOrID}
}
return image.ID(id), nil
}
// Treat it as a possible tag or digest reference
if ref, err := reference.ParseNamed(refOrID); err == nil {
if id, err := daemon.referenceStore.Get(ref); err == nil {
return id, nil
}
if tagged, ok := ref.(reference.NamedTagged); ok {
if id, err := daemon.imageStore.Search(tagged.Tag()); err == nil {
for _, namedRef := range daemon.referenceStore.References(id) {
if namedRef.Name() == ref.Name() {
return id, nil
}
}
}
}
}
// Search based on ID
if id, err := daemon.imageStore.Search(refOrID); err == nil {
return id, nil
}
return "", ErrImageDoesNotExist{refOrID}
}
// GetImage returns an image corresponding to the image referred to by refOrID.
func (daemon *Daemon) GetImage(refOrID string) (*image.Image, error) {
imgID, err := daemon.GetImageID(refOrID)
if err != nil {
return nil, err
}
return daemon.imageStore.Get(imgID)
}
// GraphDriverName returns the name of the graph driver used by the layer.Store
func (daemon *Daemon) GraphDriverName() string {
return daemon.layerStore.DriverName()
}
// ExecutionDriver returns the currently used driver for creating and
// starting execs in a container.
func (daemon *Daemon) ExecutionDriver() execdriver.Driver {
return daemon.execDriver
}
// GetUIDGIDMaps returns the current daemon's user namespace settings
// for the full uid and gid maps which will be applied to containers
// started in this instance.
func (daemon *Daemon) GetUIDGIDMaps() ([]idtools.IDMap, []idtools.IDMap) {
return daemon.uidMaps, daemon.gidMaps
}
// GetRemappedUIDGID returns the current daemon's uid and gid values
// if user namespaces are in use for this daemon instance. If not
// this function will return "real" root values of 0, 0.
func (daemon *Daemon) GetRemappedUIDGID() (int, int) {
uid, gid, _ := idtools.GetRootUIDGID(daemon.uidMaps, daemon.gidMaps)
return uid, gid
}
// ImageGetCached returns the most recent created image that is a child
// of the image with imgID, that had the same config when it was
// created. nil is returned if a child cannot be found. An error is
// returned if the parent image cannot be found.
func (daemon *Daemon) ImageGetCached(imgID image.ID, config *containertypes.Config) (*image.Image, error) {
// Loop on the children of the given image and check the config
getMatch := func(siblings []image.ID) (*image.Image, error) {
var match *image.Image
for _, id := range siblings {
img, err := daemon.imageStore.Get(id)
if err != nil {
return nil, fmt.Errorf("unable to find image %q", id)
}
if runconfig.Compare(&img.ContainerConfig, config) {
// check for the most up to date match
if match == nil || match.Created.Before(img.Created) {
match = img
}
}
}
return match, nil
}
// In this case, this is `FROM scratch`, which isn't an actual image.
if imgID == "" {
images := daemon.imageStore.Map()
var siblings []image.ID
for id, img := range images {
if img.Parent == imgID {
siblings = append(siblings, id)
}
}
return getMatch(siblings)
}
// find match from child images
siblings := daemon.imageStore.Children(imgID)
return getMatch(siblings)
}
// tempDir returns the default directory to use for temporary files.
func tempDir(rootDir string, rootUID, rootGID int) (string, error) {
var tmpDir string
if tmpDir = os.Getenv("DOCKER_TMPDIR"); tmpDir == "" {
tmpDir = filepath.Join(rootDir, "tmp")
}
return tmpDir, idtools.MkdirAllAs(tmpDir, 0700, rootUID, rootGID)
}
func (daemon *Daemon) setSecurityOptions(container *container.Container, hostConfig *containertypes.HostConfig) error {
container.Lock()
defer container.Unlock()
return parseSecurityOpt(container, hostConfig)
}
func (daemon *Daemon) setHostConfig(container *container.Container, hostConfig *containertypes.HostConfig) error {
// Do not lock while creating volumes since this could be calling out to external plugins
// Don't want to block other actions, like `docker ps` because we're waiting on an external plugin
if err := daemon.registerMountPoints(container, hostConfig); err != nil {
return err
}
container.Lock()
defer container.Unlock()
// Register any links from the host config before starting the container
if err := daemon.registerLinks(container, hostConfig); err != nil {
return err
}
// make sure links is not nil
// this ensures that on the next daemon restart we don't try to migrate from legacy sqlite links
if hostConfig.Links == nil {
hostConfig.Links = []string{}
}
container.HostConfig = hostConfig
return container.ToDisk()
}
func (daemon *Daemon) setupInitLayer(initPath string) error {
rootUID, rootGID := daemon.GetRemappedUIDGID()
return setupInitLayer(initPath, rootUID, rootGID)
}
func setDefaultMtu(config *Config) {
// do nothing if the config does not have the default 0 value.
if config.Mtu != 0 {
return
}
config.Mtu = defaultNetworkMtu
}
// verifyContainerSettings performs validation of the hostconfig and config
// structures.
func (daemon *Daemon) verifyContainerSettings(hostConfig *containertypes.HostConfig, config *containertypes.Config) ([]string, error) {
// First perform verification of settings common across all platforms.
if config != nil {
if config.WorkingDir != "" {
config.WorkingDir = filepath.FromSlash(config.WorkingDir) // Ensure in platform semantics
if !system.IsAbs(config.WorkingDir) {
return nil, fmt.Errorf("The working directory '%s' is invalid. It needs to be an absolute path.", config.WorkingDir)
}
}
if len(config.StopSignal) > 0 {
_, err := signal.ParseSignal(config.StopSignal)
if err != nil {
return nil, err
}
}
}
if hostConfig == nil {
return nil, nil
}
for port := range hostConfig.PortBindings {
_, portStr := nat.SplitProtoPort(string(port))
if _, err := nat.ParsePort(portStr); err != nil {
return nil, fmt.Errorf("Invalid port specification: %q", portStr)
}
for _, pb := range hostConfig.PortBindings[port] {
_, err := nat.NewPort(nat.SplitProtoPort(pb.HostPort))
if err != nil {
return nil, fmt.Errorf("Invalid port specification: %q", pb.HostPort)
}
}
}
// Now do platform-specific verification
return verifyPlatformContainerSettings(daemon, hostConfig, config)
}
// Checks if the client set configurations for more than one network while creating a container
func (daemon *Daemon) verifyNetworkingConfig(nwConfig *networktypes.NetworkingConfig) error {
if nwConfig == nil || len(nwConfig.EndpointsConfig) <= 1 {
return nil
}
l := make([]string, 0, len(nwConfig.EndpointsConfig))
for k := range nwConfig.EndpointsConfig {
l = append(l, k)
}
return derr.ErrorCodeMultipleNetworkConnect.WithArgs(fmt.Sprintf("%v", l))
}
func configureVolumes(config *Config, rootUID, rootGID int) (*store.VolumeStore, error) {
volumesDriver, err := local.New(config.Root, rootUID, rootGID)
if err != nil {
return nil, err
}
volumedrivers.Register(volumesDriver, volumesDriver.Name())
return store.New(), nil
}
// AuthenticateToRegistry checks the validity of credentials in authConfig
func (daemon *Daemon) AuthenticateToRegistry(authConfig *types.AuthConfig) (string, error) {
return daemon.RegistryService.Auth(authConfig)
}
// SearchRegistryForImages queries the registry for images matching
// term. authConfig is used to login.
func (daemon *Daemon) SearchRegistryForImages(term string,
authConfig *types.AuthConfig,
headers map[string][]string) (*registrytypes.SearchResults, error) {
return daemon.RegistryService.Search(term, authConfig, headers)
}
// IsShuttingDown tells whether the daemon is shutting down or not
func (daemon *Daemon) IsShuttingDown() bool {
return daemon.shutdown
}
// GetContainerStats collects all the stats published by a container
func (daemon *Daemon) GetContainerStats(container *container.Container) (*execdriver.ResourceStats, error) {
stats, err := daemon.stats(container)
if err != nil {
return nil, err
}
// Retrieve the nw statistics from libnetwork and inject them in the Stats
var nwStats []*libcontainer.NetworkInterface
if nwStats, err = daemon.getNetworkStats(container); err != nil {
return nil, err
}
stats.Interfaces = nwStats
return stats, nil
}
func (daemon *Daemon) getNetworkStats(c *container.Container) ([]*libcontainer.NetworkInterface, error) {
var list []*libcontainer.NetworkInterface
sb, err := daemon.netController.SandboxByID(c.NetworkSettings.SandboxID)
if err != nil {
return list, err
}
stats, err := sb.Statistics()
if err != nil {
return list, err
}
// Convert libnetwork nw stats into libcontainer nw stats
for ifName, ifStats := range stats {
list = append(list, convertLnNetworkStats(ifName, ifStats))
}
return list, nil
}
// newBaseContainer creates a new container with its initial
// configuration based on the root storage from the daemon.
func (daemon *Daemon) newBaseContainer(id string) *container.Container {
return container.NewBaseContainer(id, daemon.containerRoot(id))
}
// initDiscovery initializes the discovery watcher for this daemon.
func (daemon *Daemon) initDiscovery(config *Config) error {
advertise, err := parseClusterAdvertiseSettings(config.ClusterStore, config.ClusterAdvertise)
if err != nil {
if err == errDiscoveryDisabled {
return nil
}
return err
}
config.ClusterAdvertise = advertise
discoveryWatcher, err := initDiscovery(config.ClusterStore, config.ClusterAdvertise, config.ClusterOpts)
if err != nil {
return fmt.Errorf("discovery initialization failed (%v)", err)
}
daemon.discoveryWatcher = discoveryWatcher
return nil
}
// Reload reads configuration changes and modifies the
// daemon according to those changes.
// This are the settings that Reload changes:
// - Daemon labels.
func (daemon *Daemon) Reload(config *Config) error {
daemon.configStore.reloadLock.Lock()
daemon.configStore.Labels = config.Labels
daemon.configStore.reloadLock.Unlock()
return nil
}
func (daemon *Daemon) reloadClusterDiscovery(config *Config) error {
newAdvertise, err := parseClusterAdvertiseSettings(config.ClusterStore, config.ClusterAdvertise)
if err != nil && err != errDiscoveryDisabled {
return err
}
// check discovery modifications
if !modifiedDiscoverySettings(daemon.configStore, newAdvertise, config.ClusterStore, config.ClusterOpts) {
return nil
}
// enable discovery for the first time if it was not previously enabled
if daemon.discoveryWatcher == nil {
discoveryWatcher, err := initDiscovery(config.ClusterStore, newAdvertise, config.ClusterOpts)
if err != nil {
return fmt.Errorf("discovery initialization failed (%v)", err)
}
daemon.discoveryWatcher = discoveryWatcher
} else {
if err == errDiscoveryDisabled {
// disable discovery if it was previously enabled and it's disabled now
daemon.discoveryWatcher.Stop()
} else {
// reload discovery
if err = daemon.discoveryWatcher.Reload(config.ClusterStore, newAdvertise, config.ClusterOpts); err != nil {
return err
}
}
}
daemon.configStore.ClusterStore = config.ClusterStore
daemon.configStore.ClusterOpts = config.ClusterOpts
daemon.configStore.ClusterAdvertise = newAdvertise
return nil
}
func convertLnNetworkStats(name string, stats *lntypes.InterfaceStatistics) *libcontainer.NetworkInterface {
n := &libcontainer.NetworkInterface{Name: name}
n.RxBytes = stats.RxBytes
n.RxPackets = stats.RxPackets
n.RxErrors = stats.RxErrors
n.RxDropped = stats.RxDropped
n.TxBytes = stats.TxBytes
n.TxPackets = stats.TxPackets
n.TxErrors = stats.TxErrors
n.TxDropped = stats.TxDropped
return n
}
func validateID(id string) error {
if id == "" {
return derr.ErrorCodeEmptyID
}
return nil
}