package daemon import ( "bytes" "encoding/json" "errors" "fmt" "io" "io/ioutil" "os" "path" "path/filepath" "strings" "sync" "syscall" "time" "github.com/docker/libcontainer/configs" "github.com/docker/libcontainer/devices" "github.com/docker/libcontainer/label" "github.com/Sirupsen/logrus" "github.com/docker/docker/daemon/execdriver" "github.com/docker/docker/daemon/logger" "github.com/docker/docker/daemon/logger/jsonfilelog" "github.com/docker/docker/daemon/network" "github.com/docker/docker/daemon/networkdriver/bridge" "github.com/docker/docker/image" "github.com/docker/docker/links" "github.com/docker/docker/nat" "github.com/docker/docker/pkg/archive" "github.com/docker/docker/pkg/broadcastwriter" "github.com/docker/docker/pkg/directory" "github.com/docker/docker/pkg/etchosts" "github.com/docker/docker/pkg/ioutils" "github.com/docker/docker/pkg/jsonlog" "github.com/docker/docker/pkg/promise" "github.com/docker/docker/pkg/resolvconf" "github.com/docker/docker/pkg/stringid" "github.com/docker/docker/pkg/symlink" "github.com/docker/docker/pkg/ulimit" "github.com/docker/docker/runconfig" "github.com/docker/docker/utils" ) const DefaultPathEnv = "/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin" var ( ErrNotATTY = errors.New("The PTY is not a file") ErrNoTTY = errors.New("No PTY found") ErrContainerStart = errors.New("The container failed to start. Unknown error") ErrContainerStartTimeout = errors.New("The container failed to start due to timed out.") ) type StreamConfig struct { stdout *broadcastwriter.BroadcastWriter stderr *broadcastwriter.BroadcastWriter stdin io.ReadCloser stdinPipe io.WriteCloser } type Container struct { *State `json:"State"` // Needed for remote api version <= 1.11 root string // Path to the "home" of the container, including metadata. basefs string // Path to the graphdriver mountpoint ID string Created time.Time Path string Args []string Config *runconfig.Config ImageID string `json:"Image"` NetworkSettings *network.Settings ResolvConfPath string HostnamePath string HostsPath string LogPath string Name string Driver string ExecDriver string command *execdriver.Command StreamConfig daemon *Daemon MountLabel, ProcessLabel string AppArmorProfile string RestartCount int UpdateDns bool // Maps container paths to volume paths. The key in this is the path to which // the volume is being mounted inside the container. Value is the path of the // volume on disk Volumes map[string]string // Store rw/ro in a separate structure to preserve reverse-compatibility on-disk. // Easier than migrating older container configs :) VolumesRW map[string]bool hostConfig *runconfig.HostConfig activeLinks map[string]*links.Link monitor *containerMonitor execCommands *execStore // logDriver for closing logDriver logger.Logger logCopier *logger.Copier AppliedVolumesFrom map[string]struct{} } func (container *Container) FromDisk() error { pth, err := container.jsonPath() if err != nil { return err } jsonSource, err := os.Open(pth) if err != nil { return err } defer jsonSource.Close() dec := json.NewDecoder(jsonSource) // Load container settings // udp broke compat of docker.PortMapping, but it's not used when loading a container, we can skip it if err := dec.Decode(container); err != nil && !strings.Contains(err.Error(), "docker.PortMapping") { return err } if err := label.ReserveLabel(container.ProcessLabel); err != nil { return err } return container.readHostConfig() } func (container *Container) toDisk() error { data, err := json.Marshal(container) if err != nil { return err } pth, err := container.jsonPath() if err != nil { return err } if err := ioutil.WriteFile(pth, data, 0666); err != nil { return err } return container.WriteHostConfig() } func (container *Container) ToDisk() error { container.Lock() err := container.toDisk() container.Unlock() return err } func (container *Container) readHostConfig() error { container.hostConfig = &runconfig.HostConfig{} // If the hostconfig file does not exist, do not read it. // (We still have to initialize container.hostConfig, // but that's OK, since we just did that above.) pth, err := container.hostConfigPath() if err != nil { return err } _, err = os.Stat(pth) if os.IsNotExist(err) { return nil } f, err := os.Open(pth) if err != nil { return err } defer f.Close() return json.NewDecoder(f).Decode(&container.hostConfig) } func (container *Container) WriteHostConfig() error { data, err := json.Marshal(container.hostConfig) if err != nil { return err } pth, err := container.hostConfigPath() if err != nil { return err } return ioutil.WriteFile(pth, data, 0666) } func (container *Container) LogEvent(action string) { d := container.daemon d.EventsService.Log( action, container.ID, container.Config.Image, ) } // Evaluates `path` in the scope of the container's basefs, with proper path // sanitisation. Symlinks are all scoped to the basefs of the container, as // though the container's basefs was `/`. // // The basefs of a container is the host-facing path which is bind-mounted as // `/` inside the container. This method is essentially used to access a // particular path inside the container as though you were a process in that // container. // // NOTE: The returned path is *only* safely scoped inside the container's basefs // if no component of the returned path changes (such as a component // symlinking to a different path) between using this method and using the // path. See symlink.FollowSymlinkInScope for more details. func (container *Container) GetResourcePath(path string) (string, error) { cleanPath := filepath.Join("/", path) return symlink.FollowSymlinkInScope(filepath.Join(container.basefs, cleanPath), container.basefs) } // Evaluates `path` in the scope of the container's root, with proper path // sanitisation. Symlinks are all scoped to the root of the container, as // though the container's root was `/`. // // The root of a container is the host-facing configuration metadata directory. // Only use this method to safely access the container's `container.json` or // other metadata files. If in doubt, use container.GetResourcePath. // // NOTE: The returned path is *only* safely scoped inside the container's root // if no component of the returned path changes (such as a component // symlinking to a different path) between using this method and using the // path. See symlink.FollowSymlinkInScope for more details. func (container *Container) GetRootResourcePath(path string) (string, error) { cleanPath := filepath.Join("/", path) return symlink.FollowSymlinkInScope(filepath.Join(container.root, cleanPath), container.root) } func getDevicesFromPath(deviceMapping runconfig.DeviceMapping) (devs []*configs.Device, err error) { device, err := devices.DeviceFromPath(deviceMapping.PathOnHost, deviceMapping.CgroupPermissions) // if there was no error, return the device if err == nil { device.Path = deviceMapping.PathInContainer return append(devs, device), nil } // if the device is not a device node // try to see if it's a directory holding many devices if err == devices.ErrNotADevice { // check if it is a directory if src, e := os.Stat(deviceMapping.PathOnHost); e == nil && src.IsDir() { // mount the internal devices recursively filepath.Walk(deviceMapping.PathOnHost, func(dpath string, f os.FileInfo, e error) error { childDevice, e := devices.DeviceFromPath(dpath, deviceMapping.CgroupPermissions) if e != nil { // ignore the device return nil } // add the device to userSpecified devices childDevice.Path = strings.Replace(dpath, deviceMapping.PathOnHost, deviceMapping.PathInContainer, 1) devs = append(devs, childDevice) return nil }) } } if len(devs) > 0 { return devs, nil } return devs, fmt.Errorf("error gathering device information while adding custom device %q: %s", deviceMapping.PathOnHost, err) } func populateCommand(c *Container, env []string) error { en := &execdriver.Network{ Mtu: c.daemon.config.Mtu, Interface: nil, } parts := strings.SplitN(string(c.hostConfig.NetworkMode), ":", 2) switch parts[0] { case "none": case "host": en.HostNetworking = true case "bridge", "": // empty string to support existing containers if !c.Config.NetworkDisabled { network := c.NetworkSettings en.Interface = &execdriver.NetworkInterface{ Gateway: network.Gateway, Bridge: network.Bridge, IPAddress: network.IPAddress, IPPrefixLen: network.IPPrefixLen, MacAddress: network.MacAddress, LinkLocalIPv6Address: network.LinkLocalIPv6Address, GlobalIPv6Address: network.GlobalIPv6Address, GlobalIPv6PrefixLen: network.GlobalIPv6PrefixLen, IPv6Gateway: network.IPv6Gateway, HairpinMode: network.HairpinMode, } } case "container": nc, err := c.getNetworkedContainer() if err != nil { return err } en.ContainerID = nc.ID default: return fmt.Errorf("invalid network mode: %s", c.hostConfig.NetworkMode) } ipc := &execdriver.Ipc{} if c.hostConfig.IpcMode.IsContainer() { ic, err := c.getIpcContainer() if err != nil { return err } ipc.ContainerID = ic.ID } else { ipc.HostIpc = c.hostConfig.IpcMode.IsHost() } pid := &execdriver.Pid{} pid.HostPid = c.hostConfig.PidMode.IsHost() uts := &execdriver.UTS{ HostUTS: c.hostConfig.UTSMode.IsHost(), } // Build lists of devices allowed and created within the container. var userSpecifiedDevices []*configs.Device for _, deviceMapping := range c.hostConfig.Devices { devs, err := getDevicesFromPath(deviceMapping) if err != nil { return err } userSpecifiedDevices = append(userSpecifiedDevices, devs...) } allowedDevices := append(configs.DefaultAllowedDevices, userSpecifiedDevices...) autoCreatedDevices := append(configs.DefaultAutoCreatedDevices, userSpecifiedDevices...) // TODO: this can be removed after lxc-conf is fully deprecated lxcConfig, err := mergeLxcConfIntoOptions(c.hostConfig) if err != nil { return err } var rlimits []*ulimit.Rlimit ulimits := c.hostConfig.Ulimits // Merge ulimits with daemon defaults ulIdx := make(map[string]*ulimit.Ulimit) for _, ul := range ulimits { ulIdx[ul.Name] = ul } for name, ul := range c.daemon.config.Ulimits { if _, exists := ulIdx[name]; !exists { ulimits = append(ulimits, ul) } } for _, limit := range ulimits { rl, err := limit.GetRlimit() if err != nil { return err } rlimits = append(rlimits, rl) } resources := &execdriver.Resources{ Memory: c.hostConfig.Memory, MemorySwap: c.hostConfig.MemorySwap, CpuShares: c.hostConfig.CpuShares, CpusetCpus: c.hostConfig.CpusetCpus, CpusetMems: c.hostConfig.CpusetMems, CpuPeriod: c.hostConfig.CpuPeriod, CpuQuota: c.hostConfig.CpuQuota, BlkioWeight: c.hostConfig.BlkioWeight, Rlimits: rlimits, OomKillDisable: c.hostConfig.OomKillDisable, } processConfig := execdriver.ProcessConfig{ Privileged: c.hostConfig.Privileged, Entrypoint: c.Path, Arguments: c.Args, Tty: c.Config.Tty, User: c.Config.User, } processConfig.SysProcAttr = &syscall.SysProcAttr{Setsid: true} processConfig.Env = env c.command = &execdriver.Command{ ID: c.ID, Rootfs: c.RootfsPath(), ReadonlyRootfs: c.hostConfig.ReadonlyRootfs, InitPath: "/.dockerinit", WorkingDir: c.Config.WorkingDir, Network: en, Ipc: ipc, Pid: pid, UTS: uts, Resources: resources, AllowedDevices: allowedDevices, AutoCreatedDevices: autoCreatedDevices, CapAdd: c.hostConfig.CapAdd, CapDrop: c.hostConfig.CapDrop, ProcessConfig: processConfig, ProcessLabel: c.GetProcessLabel(), MountLabel: c.GetMountLabel(), LxcConfig: lxcConfig, AppArmorProfile: c.AppArmorProfile, CgroupParent: c.hostConfig.CgroupParent, } return nil } func (container *Container) Start() (err error) { container.Lock() defer container.Unlock() if container.Running { return nil } if container.removalInProgress || container.Dead { return fmt.Errorf("Container is marked for removal and cannot be started.") } // if we encounter an error during start we need to ensure that any other // setup has been cleaned up properly defer func() { if err != nil { container.setError(err) // if no one else has set it, make sure we don't leave it at zero if container.ExitCode == 0 { container.ExitCode = 128 } container.toDisk() container.cleanup() } }() if err := container.setupContainerDns(); err != nil { return err } if err := container.Mount(); err != nil { return err } if err := container.initializeNetworking(); err != nil { return err } if err := container.updateParentsHosts(); err != nil { return err } container.verifyDaemonSettings() if err := container.prepareVolumes(); err != nil { return err } linkedEnv, err := container.setupLinkedContainers() if err != nil { return err } if err := container.setupWorkingDirectory(); err != nil { return err } env := container.createDaemonEnvironment(linkedEnv) if err := populateCommand(container, env); err != nil { return err } if err := container.setupMounts(); err != nil { return err } return container.waitForStart() } func (container *Container) Run() error { if err := container.Start(); err != nil { return err } container.WaitStop(-1 * time.Second) return nil } func (container *Container) Output() (output []byte, err error) { pipe := container.StdoutPipe() defer pipe.Close() if err := container.Start(); err != nil { return nil, err } output, err = ioutil.ReadAll(pipe) container.WaitStop(-1 * time.Second) return output, err } // StreamConfig.StdinPipe returns a WriteCloser which can be used to feed data // to the standard input of the container's active process. // Container.StdoutPipe and Container.StderrPipe each return a ReadCloser // which can be used to retrieve the standard output (and error) generated // by the container's active process. The output (and error) are actually // copied and delivered to all StdoutPipe and StderrPipe consumers, using // a kind of "broadcaster". func (streamConfig *StreamConfig) StdinPipe() io.WriteCloser { return streamConfig.stdinPipe } func (streamConfig *StreamConfig) StdoutPipe() io.ReadCloser { reader, writer := io.Pipe() streamConfig.stdout.AddWriter(writer, "") return ioutils.NewBufReader(reader) } func (streamConfig *StreamConfig) StderrPipe() io.ReadCloser { reader, writer := io.Pipe() streamConfig.stderr.AddWriter(writer, "") return ioutils.NewBufReader(reader) } func (streamConfig *StreamConfig) StdoutLogPipe() io.ReadCloser { reader, writer := io.Pipe() streamConfig.stdout.AddWriter(writer, "stdout") return ioutils.NewBufReader(reader) } func (streamConfig *StreamConfig) StderrLogPipe() io.ReadCloser { reader, writer := io.Pipe() streamConfig.stderr.AddWriter(writer, "stderr") return ioutils.NewBufReader(reader) } func (container *Container) buildHostnameFile() error { hostnamePath, err := container.GetRootResourcePath("hostname") if err != nil { return err } container.HostnamePath = hostnamePath if container.Config.Domainname != "" { return ioutil.WriteFile(container.HostnamePath, []byte(fmt.Sprintf("%s.%s\n", container.Config.Hostname, container.Config.Domainname)), 0644) } return ioutil.WriteFile(container.HostnamePath, []byte(container.Config.Hostname+"\n"), 0644) } func (container *Container) buildHostsFiles(IP string) error { hostsPath, err := container.GetRootResourcePath("hosts") if err != nil { return err } container.HostsPath = hostsPath var extraContent []etchosts.Record children, err := container.daemon.Children(container.Name) if err != nil { return err } for linkAlias, child := range children { _, alias := path.Split(linkAlias) // allow access to the linked container via the alias, real name, and container hostname aliasList := alias + " " + child.Config.Hostname // only add the name if alias isn't equal to the name if alias != child.Name[1:] { aliasList = aliasList + " " + child.Name[1:] } extraContent = append(extraContent, etchosts.Record{Hosts: aliasList, IP: child.NetworkSettings.IPAddress}) } for _, extraHost := range container.hostConfig.ExtraHosts { // allow IPv6 addresses in extra hosts; only split on first ":" parts := strings.SplitN(extraHost, ":", 2) extraContent = append(extraContent, etchosts.Record{Hosts: parts[0], IP: parts[1]}) } return etchosts.Build(container.HostsPath, IP, container.Config.Hostname, container.Config.Domainname, extraContent) } func (container *Container) buildHostnameAndHostsFiles(IP string) error { if err := container.buildHostnameFile(); err != nil { return err } return container.buildHostsFiles(IP) } func (container *Container) AllocateNetwork() error { mode := container.hostConfig.NetworkMode if container.Config.NetworkDisabled || !mode.IsPrivate() { return nil } var err error networkSettings, err := bridge.Allocate(container.ID, container.Config.MacAddress, "", "") if err != nil { return err } // Error handling: At this point, the interface is allocated so we have to // make sure that it is always released in case of error, otherwise we // might leak resources. if container.Config.PortSpecs != nil { if err = migratePortMappings(container.Config, container.hostConfig); err != nil { bridge.Release(container.ID) return err } container.Config.PortSpecs = nil if err = container.WriteHostConfig(); err != nil { bridge.Release(container.ID) return err } } var ( portSpecs = make(nat.PortSet) bindings = make(nat.PortMap) ) if container.Config.ExposedPorts != nil { portSpecs = container.Config.ExposedPorts } if container.hostConfig.PortBindings != nil { for p, b := range container.hostConfig.PortBindings { bindings[p] = []nat.PortBinding{} for _, bb := range b { bindings[p] = append(bindings[p], nat.PortBinding{ HostIp: bb.HostIp, HostPort: bb.HostPort, }) } } } container.NetworkSettings.PortMapping = nil ports := make([]nat.Port, len(portSpecs)) var i int for p := range portSpecs { ports[i] = p i++ } nat.SortPortMap(ports, bindings) for _, port := range ports { if err = container.allocatePort(port, bindings); err != nil { bridge.Release(container.ID) return err } } container.WriteHostConfig() networkSettings.Ports = bindings container.NetworkSettings = networkSettings return nil } func (container *Container) ReleaseNetwork() { if container.Config.NetworkDisabled || !container.hostConfig.NetworkMode.IsPrivate() { return } bridge.Release(container.ID) container.NetworkSettings = &network.Settings{} } func (container *Container) isNetworkAllocated() bool { return container.NetworkSettings.IPAddress != "" } func (container *Container) RestoreNetwork() error { mode := container.hostConfig.NetworkMode // Don't attempt a restore if we previously didn't allocate networking. // This might be a legacy container with no network allocated, in which case the // allocation will happen once and for all at start. if !container.isNetworkAllocated() || container.Config.NetworkDisabled || !mode.IsPrivate() { return nil } // Re-allocate the interface with the same IP and MAC address. if _, err := bridge.Allocate(container.ID, container.NetworkSettings.MacAddress, container.NetworkSettings.IPAddress, ""); err != nil { return err } // Re-allocate any previously allocated ports. for port := range container.NetworkSettings.Ports { if err := container.allocatePort(port, container.NetworkSettings.Ports); err != nil { return err } } return nil } // cleanup releases any network resources allocated to the container along with any rules // around how containers are linked together. It also unmounts the container's root filesystem. func (container *Container) cleanup() { container.ReleaseNetwork() // Disable all active links if container.activeLinks != nil { for _, link := range container.activeLinks { link.Disable() } } if err := container.Unmount(); err != nil { logrus.Errorf("%v: Failed to umount filesystem: %v", container.ID, err) } for _, eConfig := range container.execCommands.s { container.daemon.unregisterExecCommand(eConfig) } } func (container *Container) KillSig(sig int) error { logrus.Debugf("Sending %d to %s", sig, container.ID) container.Lock() defer container.Unlock() // We could unpause the container for them rather than returning this error if container.Paused { return fmt.Errorf("Container %s is paused. Unpause the container before stopping", container.ID) } if !container.Running { return nil } // signal to the monitor that it should not restart the container // after we send the kill signal container.monitor.ExitOnNext() // if the container is currently restarting we do not need to send the signal // to the process. Telling the monitor that it should exit on it's next event // loop is enough if container.Restarting { return nil } return container.daemon.Kill(container, sig) } // Wrapper aroung KillSig() suppressing "no such process" error. func (container *Container) killPossiblyDeadProcess(sig int) error { err := container.KillSig(sig) if err == syscall.ESRCH { logrus.Debugf("Cannot kill process (pid=%d) with signal %d: no such process.", container.GetPid(), sig) return nil } return err } func (container *Container) Pause() error { container.Lock() defer container.Unlock() // We cannot Pause the container which is already paused if container.Paused { return fmt.Errorf("Container %s is already paused", container.ID) } // We cannot Pause the container which is not running if !container.Running { return fmt.Errorf("Container %s is not running", container.ID) } if err := container.daemon.execDriver.Pause(container.command); err != nil { return err } container.Paused = true return nil } func (container *Container) Unpause() error { container.Lock() defer container.Unlock() // We cannot unpause the container which is not paused if !container.Paused { return fmt.Errorf("Container %s is not paused, so what", container.ID) } // We cannot unpause the container which is not running if !container.Running { return fmt.Errorf("Container %s is not running", container.ID) } if err := container.daemon.execDriver.Unpause(container.command); err != nil { return err } container.Paused = false return nil } func (container *Container) Kill() error { if !container.IsRunning() { return nil } // 1. Send SIGKILL if err := container.killPossiblyDeadProcess(9); err != nil { return err } // 2. Wait for the process to die, in last resort, try to kill the process directly if _, err := container.WaitStop(10 * time.Second); err != nil { // Ensure that we don't kill ourselves if pid := container.GetPid(); pid != 0 { logrus.Infof("Container %s failed to exit within 10 seconds of kill - trying direct SIGKILL", stringid.TruncateID(container.ID)) if err := syscall.Kill(pid, 9); err != nil { if err != syscall.ESRCH { return err } logrus.Debugf("Cannot kill process (pid=%d) with signal 9: no such process.", pid) } } } container.WaitStop(-1 * time.Second) return nil } func (container *Container) Stop(seconds int) error { if !container.IsRunning() { return nil } // 1. Send a SIGTERM if err := container.killPossiblyDeadProcess(15); err != nil { logrus.Infof("Failed to send SIGTERM to the process, force killing") if err := container.killPossiblyDeadProcess(9); err != nil { return err } } // 2. Wait for the process to exit on its own if _, err := container.WaitStop(time.Duration(seconds) * time.Second); err != nil { logrus.Infof("Container %v failed to exit within %d seconds of SIGTERM - using the force", container.ID, seconds) // 3. If it doesn't, then send SIGKILL if err := container.Kill(); err != nil { container.WaitStop(-1 * time.Second) return err } } return nil } func (container *Container) Restart(seconds int) error { // Avoid unnecessarily unmounting and then directly mounting // the container when the container stops and then starts // again if err := container.Mount(); err == nil { defer container.Unmount() } if err := container.Stop(seconds); err != nil { return err } return container.Start() } func (container *Container) Resize(h, w int) error { if !container.IsRunning() { return fmt.Errorf("Cannot resize container %s, container is not running", container.ID) } return container.command.ProcessConfig.Terminal.Resize(h, w) } func (container *Container) ExportRw() (archive.Archive, error) { if err := container.Mount(); err != nil { return nil, err } if container.daemon == nil { return nil, fmt.Errorf("Can't load storage driver for unregistered container %s", container.ID) } archive, err := container.daemon.Diff(container) if err != nil { container.Unmount() return nil, err } return ioutils.NewReadCloserWrapper(archive, func() error { err := archive.Close() container.Unmount() return err }), nil } func (container *Container) Export() (archive.Archive, error) { if err := container.Mount(); err != nil { return nil, err } archive, err := archive.Tar(container.basefs, archive.Uncompressed) if err != nil { container.Unmount() return nil, err } return ioutils.NewReadCloserWrapper(archive, func() error { err := archive.Close() container.Unmount() return err }), nil } func (container *Container) Mount() error { return container.daemon.Mount(container) } func (container *Container) changes() ([]archive.Change, error) { return container.daemon.Changes(container) } func (container *Container) Changes() ([]archive.Change, error) { container.Lock() defer container.Unlock() return container.changes() } func (container *Container) GetImage() (*image.Image, error) { if container.daemon == nil { return nil, fmt.Errorf("Can't get image of unregistered container") } return container.daemon.graph.Get(container.ImageID) } func (container *Container) Unmount() error { return container.daemon.Unmount(container) } func (container *Container) hostConfigPath() (string, error) { return container.GetRootResourcePath("hostconfig.json") } func (container *Container) jsonPath() (string, error) { return container.GetRootResourcePath("config.json") } // This method must be exported to be used from the lxc template // This directory is only usable when the container is running func (container *Container) RootfsPath() string { return container.basefs } func validateID(id string) error { if id == "" { return fmt.Errorf("Invalid empty id") } return nil } // GetSize, return real size, virtual size func (container *Container) GetSize() (int64, int64) { var ( sizeRw, sizeRootfs int64 err error driver = container.daemon.driver ) if err := container.Mount(); err != nil { logrus.Errorf("Failed to compute size of container rootfs %s: %s", container.ID, err) return sizeRw, sizeRootfs } defer container.Unmount() initID := fmt.Sprintf("%s-init", container.ID) sizeRw, err = driver.DiffSize(container.ID, initID) if err != nil { logrus.Errorf("Driver %s couldn't return diff size of container %s: %s", driver, container.ID, err) // FIXME: GetSize should return an error. Not changing it now in case // there is a side-effect. sizeRw = -1 } if _, err = os.Stat(container.basefs); err != nil { if sizeRootfs, err = directory.Size(container.basefs); err != nil { sizeRootfs = -1 } } return sizeRw, sizeRootfs } func (container *Container) Copy(resource string) (io.ReadCloser, error) { container.Lock() defer container.Unlock() var err error if err := container.Mount(); err != nil { return nil, err } defer func() { if err != nil { container.Unmount() } }() if err = container.mountVolumes(); err != nil { container.unmountVolumes() return nil, err } defer func() { if err != nil { container.unmountVolumes() } }() basePath, err := container.GetResourcePath(resource) if err != nil { return nil, err } stat, err := os.Stat(basePath) if err != nil { return nil, err } var filter []string if !stat.IsDir() { d, f := path.Split(basePath) basePath = d filter = []string{f} } else { filter = []string{path.Base(basePath)} basePath = path.Dir(basePath) } archive, err := archive.TarWithOptions(basePath, &archive.TarOptions{ Compression: archive.Uncompressed, IncludeFiles: filter, }) if err != nil { return nil, err } return ioutils.NewReadCloserWrapper(archive, func() error { err := archive.Close() container.unmountVolumes() container.Unmount() return err }), nil } // Returns true if the container exposes a certain port func (container *Container) Exposes(p nat.Port) bool { _, exists := container.Config.ExposedPorts[p] return exists } func (container *Container) HostConfig() *runconfig.HostConfig { return container.hostConfig } func (container *Container) SetHostConfig(hostConfig *runconfig.HostConfig) { container.hostConfig = hostConfig } func (container *Container) DisableLink(name string) { if container.activeLinks != nil { if link, exists := container.activeLinks[name]; exists { link.Disable() } else { logrus.Debugf("Could not find active link for %s", name) } } } func (container *Container) setupContainerDns() error { if container.ResolvConfPath != "" { // check if this is an existing container that needs DNS update: if container.UpdateDns { // read the host's resolv.conf, get the hash and call updateResolvConf logrus.Debugf("Check container (%s) for update to resolv.conf - UpdateDns flag was set", container.ID) latestResolvConf, latestHash := resolvconf.GetLastModified() // clean container resolv.conf re: localhost nameservers and IPv6 NS (if IPv6 disabled) updatedResolvConf, modified := resolvconf.FilterResolvDns(latestResolvConf, container.daemon.config.Bridge.EnableIPv6) if modified { // changes have occurred during resolv.conf localhost cleanup: generate an updated hash newHash, err := ioutils.HashData(bytes.NewReader(updatedResolvConf)) if err != nil { return err } latestHash = newHash } if err := container.updateResolvConf(updatedResolvConf, latestHash); err != nil { return err } // successful update of the restarting container; set the flag off container.UpdateDns = false } return nil } var ( config = container.hostConfig daemon = container.daemon ) resolvConf, err := resolvconf.Get() if err != nil { return err } container.ResolvConfPath, err = container.GetRootResourcePath("resolv.conf") if err != nil { return err } if config.NetworkMode.IsBridge() || config.NetworkMode.IsNone() { // check configurations for any container/daemon dns settings if len(config.Dns) > 0 || len(daemon.config.Dns) > 0 || len(config.DnsSearch) > 0 || len(daemon.config.DnsSearch) > 0 { var ( dns = resolvconf.GetNameservers(resolvConf) dnsSearch = resolvconf.GetSearchDomains(resolvConf) ) if len(config.Dns) > 0 { dns = config.Dns } else if len(daemon.config.Dns) > 0 { dns = daemon.config.Dns } if len(config.DnsSearch) > 0 { dnsSearch = config.DnsSearch } else if len(daemon.config.DnsSearch) > 0 { dnsSearch = daemon.config.DnsSearch } return resolvconf.Build(container.ResolvConfPath, dns, dnsSearch) } // replace any localhost/127.*, and remove IPv6 nameservers if IPv6 disabled in daemon resolvConf, _ = resolvconf.FilterResolvDns(resolvConf, daemon.config.Bridge.EnableIPv6) } //get a sha256 hash of the resolv conf at this point so we can check //for changes when the host resolv.conf changes (e.g. network update) resolvHash, err := ioutils.HashData(bytes.NewReader(resolvConf)) if err != nil { return err } resolvHashFile := container.ResolvConfPath + ".hash" if err = ioutil.WriteFile(resolvHashFile, []byte(resolvHash), 0644); err != nil { return err } return ioutil.WriteFile(container.ResolvConfPath, resolvConf, 0644) } // called when the host's resolv.conf changes to check whether container's resolv.conf // is unchanged by the container "user" since container start: if unchanged, the // container's resolv.conf will be updated to match the host's new resolv.conf func (container *Container) updateResolvConf(updatedResolvConf []byte, newResolvHash string) error { if container.ResolvConfPath == "" { return nil } if container.Running { //set a marker in the hostConfig to update on next start/restart container.UpdateDns = true return nil } resolvHashFile := container.ResolvConfPath + ".hash" //read the container's current resolv.conf and compute the hash resolvBytes, err := ioutil.ReadFile(container.ResolvConfPath) if err != nil { return err } curHash, err := ioutils.HashData(bytes.NewReader(resolvBytes)) if err != nil { return err } //read the hash from the last time we wrote resolv.conf in the container hashBytes, err := ioutil.ReadFile(resolvHashFile) if err != nil { if !os.IsNotExist(err) { return err } // backwards compat: if no hash file exists, this container pre-existed from // a Docker daemon that didn't contain this update feature. Given we can't know // if the user has modified the resolv.conf since container start time, safer // to just never update the container's resolv.conf during it's lifetime which // we can control by setting hashBytes to an empty string hashBytes = []byte("") } //if the user has not modified the resolv.conf of the container since we wrote it last //we will replace it with the updated resolv.conf from the host if string(hashBytes) == curHash { logrus.Debugf("replacing %q with updated host resolv.conf", container.ResolvConfPath) // for atomic updates to these files, use temporary files with os.Rename: dir := path.Dir(container.ResolvConfPath) tmpHashFile, err := ioutil.TempFile(dir, "hash") if err != nil { return err } tmpResolvFile, err := ioutil.TempFile(dir, "resolv") if err != nil { return err } // write the updates to the temp files if err = ioutil.WriteFile(tmpHashFile.Name(), []byte(newResolvHash), 0644); err != nil { return err } if err = ioutil.WriteFile(tmpResolvFile.Name(), updatedResolvConf, 0644); err != nil { return err } // rename the temp files for atomic replace if err = os.Rename(tmpHashFile.Name(), resolvHashFile); err != nil { return err } return os.Rename(tmpResolvFile.Name(), container.ResolvConfPath) } return nil } func (container *Container) updateParentsHosts() error { refs := container.daemon.ContainerGraph().RefPaths(container.ID) for _, ref := range refs { if ref.ParentID == "0" { continue } c, err := container.daemon.Get(ref.ParentID) if err != nil { logrus.Error(err) } if c != nil && !container.daemon.config.DisableNetwork && container.hostConfig.NetworkMode.IsPrivate() { logrus.Debugf("Update /etc/hosts of %s for alias %s with ip %s", c.ID, ref.Name, container.NetworkSettings.IPAddress) if err := etchosts.Update(c.HostsPath, container.NetworkSettings.IPAddress, ref.Name); err != nil { logrus.Errorf("Failed to update /etc/hosts in parent container %s for alias %s: %v", c.ID, ref.Name, err) } } } return nil } func (container *Container) initializeNetworking() error { var err error if container.hostConfig.NetworkMode.IsHost() { container.Config.Hostname, err = os.Hostname() if err != nil { return err } parts := strings.SplitN(container.Config.Hostname, ".", 2) if len(parts) > 1 { container.Config.Hostname = parts[0] container.Config.Domainname = parts[1] } content, err := ioutil.ReadFile("/etc/hosts") if os.IsNotExist(err) { return container.buildHostnameAndHostsFiles("") } else if err != nil { return err } if err := container.buildHostnameFile(); err != nil { return err } hostsPath, err := container.GetRootResourcePath("hosts") if err != nil { return err } container.HostsPath = hostsPath return ioutil.WriteFile(container.HostsPath, content, 0644) } if container.hostConfig.NetworkMode.IsContainer() { // we need to get the hosts files from the container to join nc, err := container.getNetworkedContainer() if err != nil { return err } container.HostnamePath = nc.HostnamePath container.HostsPath = nc.HostsPath container.ResolvConfPath = nc.ResolvConfPath container.Config.Hostname = nc.Config.Hostname container.Config.Domainname = nc.Config.Domainname return nil } if container.daemon.config.DisableNetwork { container.Config.NetworkDisabled = true return container.buildHostnameAndHostsFiles("127.0.1.1") } if err := container.AllocateNetwork(); err != nil { return err } return container.buildHostnameAndHostsFiles(container.NetworkSettings.IPAddress) } // Make sure the config is compatible with the current kernel func (container *Container) verifyDaemonSettings() { if container.hostConfig.Memory > 0 && !container.daemon.sysInfo.MemoryLimit { logrus.Warnf("Your kernel does not support memory limit capabilities. Limitation discarded.") container.hostConfig.Memory = 0 } if container.hostConfig.Memory > 0 && container.hostConfig.MemorySwap != -1 && !container.daemon.sysInfo.SwapLimit { logrus.Warnf("Your kernel does not support swap limit capabilities. Limitation discarded.") container.hostConfig.MemorySwap = -1 } if container.daemon.sysInfo.IPv4ForwardingDisabled { logrus.Warnf("IPv4 forwarding is disabled. Networking will not work") } } func (container *Container) setupLinkedContainers() ([]string, error) { var ( env []string daemon = container.daemon ) children, err := daemon.Children(container.Name) if err != nil { return nil, err } if len(children) > 0 { container.activeLinks = make(map[string]*links.Link, len(children)) // If we encounter an error make sure that we rollback any network // config and iptables changes rollback := func() { for _, link := range container.activeLinks { link.Disable() } container.activeLinks = nil } for linkAlias, child := range children { if !child.IsRunning() { return nil, fmt.Errorf("Cannot link to a non running container: %s AS %s", child.Name, linkAlias) } link, err := links.NewLink( container.NetworkSettings.IPAddress, child.NetworkSettings.IPAddress, linkAlias, child.Config.Env, child.Config.ExposedPorts, ) if err != nil { rollback() return nil, err } container.activeLinks[link.Alias()] = link if err := link.Enable(); err != nil { rollback() return nil, err } for _, envVar := range link.ToEnv() { env = append(env, envVar) } } } return env, nil } func (container *Container) createDaemonEnvironment(linkedEnv []string) []string { // if a domain name was specified, append it to the hostname (see #7851) fullHostname := container.Config.Hostname if container.Config.Domainname != "" { fullHostname = fmt.Sprintf("%s.%s", fullHostname, container.Config.Domainname) } // Setup environment env := []string{ "PATH=" + DefaultPathEnv, "HOSTNAME=" + fullHostname, // Note: we don't set HOME here because it'll get autoset intelligently // based on the value of USER inside dockerinit, but only if it isn't // set already (ie, that can be overridden by setting HOME via -e or ENV // in a Dockerfile). } if container.Config.Tty { env = append(env, "TERM=xterm") } env = append(env, linkedEnv...) // because the env on the container can override certain default values // we need to replace the 'env' keys where they match and append anything // else. env = utils.ReplaceOrAppendEnvValues(env, container.Config.Env) return env } func (container *Container) setupWorkingDirectory() error { if container.Config.WorkingDir != "" { container.Config.WorkingDir = path.Clean(container.Config.WorkingDir) pth, err := container.GetResourcePath(container.Config.WorkingDir) if err != nil { return err } pthInfo, err := os.Stat(pth) if err != nil { if !os.IsNotExist(err) { return err } if err := os.MkdirAll(pth, 0755); err != nil { return err } } if pthInfo != nil && !pthInfo.IsDir() { return fmt.Errorf("Cannot mkdir: %s is not a directory", container.Config.WorkingDir) } } return nil } func (container *Container) getLogConfig() runconfig.LogConfig { cfg := container.hostConfig.LogConfig if cfg.Type != "" { // container has log driver configured return cfg } // Use daemon's default log config for containers return container.daemon.defaultLogConfig } func (container *Container) getLogger() (logger.Logger, error) { cfg := container.getLogConfig() c, err := logger.GetLogDriver(cfg.Type) if err != nil { return nil, fmt.Errorf("Failed to get logging factory: %v", err) } ctx := logger.Context{ ContainerID: container.ID, ContainerName: container.Name, } // Set logging file for "json-logger" if cfg.Type == jsonfilelog.Name { ctx.LogPath, err = container.GetRootResourcePath(fmt.Sprintf("%s-json.log", container.ID)) if err != nil { return nil, err } } return c(ctx) } func (container *Container) startLogging() error { cfg := container.getLogConfig() if cfg.Type == "none" { return nil // do not start logging routines } l, err := container.getLogger() if err != nil { return fmt.Errorf("Failed to initialize logging driver: %v", err) } copier, err := logger.NewCopier(container.ID, map[string]io.Reader{"stdout": container.StdoutPipe(), "stderr": container.StderrPipe()}, l) if err != nil { return err } container.logCopier = copier copier.Run() container.logDriver = l // set LogPath field only for json-file logdriver if jl, ok := l.(*jsonfilelog.JSONFileLogger); ok { container.LogPath = jl.LogPath() } return nil } func (container *Container) waitForStart() error { container.monitor = newContainerMonitor(container, container.hostConfig.RestartPolicy) // block until we either receive an error from the initial start of the container's // process or until the process is running in the container select { case <-container.monitor.startSignal: case err := <-promise.Go(container.monitor.Start): return err } return nil } func (container *Container) allocatePort(port nat.Port, bindings nat.PortMap) error { binding := bindings[port] if container.hostConfig.PublishAllPorts && len(binding) == 0 { binding = append(binding, nat.PortBinding{}) } for i := 0; i < len(binding); i++ { b, err := bridge.AllocatePort(container.ID, port, binding[i]) if err != nil { return err } binding[i] = b } bindings[port] = binding return nil } func (container *Container) GetProcessLabel() string { // even if we have a process label return "" if we are running // in privileged mode if container.hostConfig.Privileged { return "" } return container.ProcessLabel } func (container *Container) GetMountLabel() string { if container.hostConfig.Privileged { return "" } return container.MountLabel } func (container *Container) getIpcContainer() (*Container, error) { containerID := container.hostConfig.IpcMode.Container() c, err := container.daemon.Get(containerID) if err != nil { return nil, err } if !c.IsRunning() { return nil, fmt.Errorf("cannot join IPC of a non running container: %s", containerID) } return c, nil } func (container *Container) getNetworkedContainer() (*Container, error) { parts := strings.SplitN(string(container.hostConfig.NetworkMode), ":", 2) switch parts[0] { case "container": if len(parts) != 2 { return nil, fmt.Errorf("no container specified to join network") } nc, err := container.daemon.Get(parts[1]) if err != nil { return nil, err } if container == nc { return nil, fmt.Errorf("cannot join own network") } if !nc.IsRunning() { return nil, fmt.Errorf("cannot join network of a non running container: %s", parts[1]) } return nc, nil default: return nil, fmt.Errorf("network mode not set to container") } } func (container *Container) Stats() (*execdriver.ResourceStats, error) { return container.daemon.Stats(container) } func (c *Container) LogDriverType() string { c.Lock() defer c.Unlock() if c.hostConfig.LogConfig.Type == "" { return c.daemon.defaultLogConfig.Type } return c.hostConfig.LogConfig.Type } func (container *Container) GetExecIDs() []string { return container.execCommands.List() } func (container *Container) Exec(execConfig *execConfig) error { container.Lock() defer container.Unlock() waitStart := make(chan struct{}) callback := func(processConfig *execdriver.ProcessConfig, pid int) { if processConfig.Tty { // The callback is called after the process Start() // so we are in the parent process. In TTY mode, stdin/out/err is the PtySlave // which we close here. if c, ok := processConfig.Stdout.(io.Closer); ok { c.Close() } } close(waitStart) } // We use a callback here instead of a goroutine and an chan for // syncronization purposes cErr := promise.Go(func() error { return container.monitorExec(execConfig, callback) }) // Exec should not return until the process is actually running select { case <-waitStart: case err := <-cErr: return err } return nil } func (container *Container) monitorExec(execConfig *execConfig, callback execdriver.StartCallback) error { var ( err error exitCode int ) pipes := execdriver.NewPipes(execConfig.StreamConfig.stdin, execConfig.StreamConfig.stdout, execConfig.StreamConfig.stderr, execConfig.OpenStdin) exitCode, err = container.daemon.Exec(container, execConfig, pipes, callback) if err != nil { logrus.Errorf("Error running command in existing container %s: %s", container.ID, err) } logrus.Debugf("Exec task in container %s exited with code %d", container.ID, exitCode) if execConfig.OpenStdin { if err := execConfig.StreamConfig.stdin.Close(); err != nil { logrus.Errorf("Error closing stdin while running in %s: %s", container.ID, err) } } if err := execConfig.StreamConfig.stdout.Clean(); err != nil { logrus.Errorf("Error closing stdout while running in %s: %s", container.ID, err) } if err := execConfig.StreamConfig.stderr.Clean(); err != nil { logrus.Errorf("Error closing stderr while running in %s: %s", container.ID, err) } if execConfig.ProcessConfig.Terminal != nil { if err := execConfig.ProcessConfig.Terminal.Close(); err != nil { logrus.Errorf("Error closing terminal while running in container %s: %s", container.ID, err) } } return err } func (c *Container) Attach(stdin io.ReadCloser, stdout io.Writer, stderr io.Writer) chan error { return attach(&c.StreamConfig, c.Config.OpenStdin, c.Config.StdinOnce, c.Config.Tty, stdin, stdout, stderr) } func (c *Container) AttachWithLogs(stdin io.ReadCloser, stdout, stderr io.Writer, logs, stream bool) error { if logs { logDriver, err := c.getLogger() cLog, err := logDriver.GetReader() if err != nil { logrus.Errorf("Error reading logs: %s", err) } else if c.LogDriverType() != jsonfilelog.Name { logrus.Errorf("Reading logs not implemented for driver %s", c.LogDriverType()) } else { dec := json.NewDecoder(cLog) for { l := &jsonlog.JSONLog{} if err := dec.Decode(l); err == io.EOF { break } else if err != nil { logrus.Errorf("Error streaming logs: %s", err) break } if l.Stream == "stdout" && stdout != nil { io.WriteString(stdout, l.Log) } if l.Stream == "stderr" && stderr != nil { io.WriteString(stderr, l.Log) } } } } //stream if stream { var stdinPipe io.ReadCloser if stdin != nil { r, w := io.Pipe() go func() { defer w.Close() defer logrus.Debugf("Closing buffered stdin pipe") io.Copy(w, stdin) }() stdinPipe = r } <-c.Attach(stdinPipe, stdout, stderr) // If we are in stdinonce mode, wait for the process to end // otherwise, simply return if c.Config.StdinOnce && !c.Config.Tty { c.WaitStop(-1 * time.Second) } } return nil } func attach(streamConfig *StreamConfig, openStdin, stdinOnce, tty bool, stdin io.ReadCloser, stdout io.Writer, stderr io.Writer) chan error { var ( cStdout, cStderr io.ReadCloser cStdin io.WriteCloser wg sync.WaitGroup errors = make(chan error, 3) ) if stdin != nil && openStdin { cStdin = streamConfig.StdinPipe() wg.Add(1) } if stdout != nil { cStdout = streamConfig.StdoutPipe() wg.Add(1) } if stderr != nil { cStderr = streamConfig.StderrPipe() wg.Add(1) } // Connect stdin of container to the http conn. go func() { if stdin == nil || !openStdin { return } logrus.Debugf("attach: stdin: begin") defer func() { if stdinOnce && !tty { cStdin.Close() } else { // No matter what, when stdin is closed (io.Copy unblock), close stdout and stderr if cStdout != nil { cStdout.Close() } if cStderr != nil { cStderr.Close() } } wg.Done() logrus.Debugf("attach: stdin: end") }() var err error if tty { _, err = copyEscapable(cStdin, stdin) } else { _, err = io.Copy(cStdin, stdin) } if err == io.ErrClosedPipe { err = nil } if err != nil { logrus.Errorf("attach: stdin: %s", err) errors <- err return } }() attachStream := func(name string, stream io.Writer, streamPipe io.ReadCloser) { if stream == nil { return } defer func() { // Make sure stdin gets closed if stdin != nil { stdin.Close() } streamPipe.Close() wg.Done() logrus.Debugf("attach: %s: end", name) }() logrus.Debugf("attach: %s: begin", name) _, err := io.Copy(stream, streamPipe) if err == io.ErrClosedPipe { err = nil } if err != nil { logrus.Errorf("attach: %s: %v", name, err) errors <- err } } go attachStream("stdout", stdout, cStdout) go attachStream("stderr", stderr, cStderr) return promise.Go(func() error { wg.Wait() close(errors) for err := range errors { if err != nil { return err } } return nil }) } // Code c/c from io.Copy() modified to handle escape sequence func copyEscapable(dst io.Writer, src io.ReadCloser) (written int64, err error) { buf := make([]byte, 32*1024) for { nr, er := src.Read(buf) if nr > 0 { // ---- Docker addition // char 16 is C-p if nr == 1 && buf[0] == 16 { nr, er = src.Read(buf) // char 17 is C-q if nr == 1 && buf[0] == 17 { if err := src.Close(); err != nil { return 0, err } return 0, nil } } // ---- End of docker nw, ew := dst.Write(buf[0:nr]) if nw > 0 { written += int64(nw) } if ew != nil { err = ew break } if nr != nw { err = io.ErrShortWrite break } } if er == io.EOF { break } if er != nil { err = er break } } return written, err }