package libpod import ( "context" "os" "path" "path/filepath" "strings" "time" "github.com/containers/libpod/libpod/define" "github.com/containers/libpod/libpod/events" "github.com/containers/libpod/pkg/rootless" "github.com/containers/storage/pkg/stringid" spec "github.com/opencontainers/runtime-spec/specs-go" "github.com/opencontainers/runtime-tools/generate" "github.com/opentracing/opentracing-go" "github.com/pkg/errors" "github.com/sirupsen/logrus" ) // Contains the public Runtime API for containers // A CtrCreateOption is a functional option which alters the Container created // by NewContainer type CtrCreateOption func(*Container) error // ContainerFilter is a function to determine whether a container is included // in command output. Containers to be outputted are tested using the function. // A true return will include the container, a false return will exclude it. type ContainerFilter func(*Container) bool // NewContainer creates a new container from a given OCI config. func (r *Runtime) NewContainer(ctx context.Context, rSpec *spec.Spec, options ...CtrCreateOption) (c *Container, err error) { r.lock.Lock() defer r.lock.Unlock() if !r.valid { return nil, define.ErrRuntimeStopped } return r.newContainer(ctx, rSpec, options...) } // RestoreContainer re-creates a container from an imported checkpoint func (r *Runtime) RestoreContainer(ctx context.Context, rSpec *spec.Spec, config *ContainerConfig) (c *Container, err error) { r.lock.Lock() defer r.lock.Unlock() if !r.valid { return nil, define.ErrRuntimeStopped } ctr, err := r.initContainerVariables(rSpec, config) if err != nil { return nil, errors.Wrapf(err, "error initializing container variables") } // For an imported checkpoint no one has ever set the StartedTime. Set it now. ctr.state.StartedTime = time.Now() // If the path to ConmonPidFile starts with the default value (RunRoot), then // the user has not specified '--conmon-pidfile' during run or create (probably). // In that case reset ConmonPidFile to be set to the default value later. if strings.HasPrefix(ctr.config.ConmonPidFile, r.config.StorageConfig.RunRoot) { ctr.config.ConmonPidFile = "" } return r.setupContainer(ctx, ctr) } func (r *Runtime) initContainerVariables(rSpec *spec.Spec, config *ContainerConfig) (c *Container, err error) { if rSpec == nil { return nil, errors.Wrapf(define.ErrInvalidArg, "must provide a valid runtime spec to create container") } ctr := new(Container) ctr.config = new(ContainerConfig) ctr.state = new(ContainerState) if config == nil { ctr.config.ID = stringid.GenerateNonCryptoID() ctr.config.ShmSize = DefaultShmSize } else { // This is a restore from an imported checkpoint ctr.restoreFromCheckpoint = true if err := JSONDeepCopy(config, ctr.config); err != nil { return nil, errors.Wrapf(err, "error copying container config for restore") } // If the ID is empty a new name for the restored container was requested if ctr.config.ID == "" { ctr.config.ID = stringid.GenerateNonCryptoID() // Fixup ExitCommand with new ID ctr.config.ExitCommand[len(ctr.config.ExitCommand)-1] = ctr.config.ID } // Reset the log path to point to the default ctr.config.LogPath = "" } ctr.config.Spec = new(spec.Spec) if err := JSONDeepCopy(rSpec, ctr.config.Spec); err != nil { return nil, errors.Wrapf(err, "error copying runtime spec while creating container") } ctr.config.CreatedTime = time.Now() ctr.state.BindMounts = make(map[string]string) ctr.config.StopTimeout = define.CtrRemoveTimeout ctr.config.OCIRuntime = r.defaultOCIRuntime.name // Set namespace based on current runtime namespace // Do so before options run so they can override it if r.config.Namespace != "" { ctr.config.Namespace = r.config.Namespace } ctr.runtime = r return ctr, nil } func (r *Runtime) newContainer(ctx context.Context, rSpec *spec.Spec, options ...CtrCreateOption) (c *Container, err error) { span, _ := opentracing.StartSpanFromContext(ctx, "newContainer") span.SetTag("type", "runtime") defer span.Finish() ctr, err := r.initContainerVariables(rSpec, nil) if err != nil { return nil, errors.Wrapf(err, "error initializing container variables") } for _, option := range options { if err := option(ctr); err != nil { return nil, errors.Wrapf(err, "error running container create option") } } return r.setupContainer(ctx, ctr) } func (r *Runtime) setupContainer(ctx context.Context, ctr *Container) (c *Container, err error) { // Allocate a lock for the container lock, err := r.lockManager.AllocateLock() if err != nil { return nil, errors.Wrapf(err, "error allocating lock for new container") } ctr.lock = lock ctr.config.LockID = ctr.lock.ID() logrus.Debugf("Allocated lock %d for container %s", ctr.lock.ID(), ctr.ID()) defer func() { if err != nil { if err2 := ctr.lock.Free(); err2 != nil { logrus.Errorf("Error freeing lock for container after creation failed: %v", err2) } } }() ctr.valid = true ctr.state.State = define.ContainerStateConfigured ctr.runtime = r if ctr.config.OCIRuntime == "" { ctr.ociRuntime = r.defaultOCIRuntime } else { ociRuntime, ok := r.ociRuntimes[ctr.config.OCIRuntime] if !ok { return nil, errors.Wrapf(define.ErrInvalidArg, "requested OCI runtime %s is not available", ctr.config.OCIRuntime) } ctr.ociRuntime = ociRuntime } // Check NoCgroups support if ctr.config.NoCgroups { if !ctr.ociRuntime.supportsNoCgroups { return nil, errors.Wrapf(define.ErrInvalidArg, "requested OCI runtime %s is not compatible with NoCgroups", ctr.ociRuntime.name) } } var pod *Pod if ctr.config.Pod != "" { // Get the pod from state pod, err = r.state.Pod(ctr.config.Pod) if err != nil { return nil, errors.Wrapf(err, "cannot add container %s to pod %s", ctr.ID(), ctr.config.Pod) } } if ctr.config.Name == "" { name, err := r.generateName() if err != nil { return nil, err } ctr.config.Name = name } // If CGroups are disabled, we MUST create a PID namespace. // Otherwise, the OCI runtime won't be able to stop our container. if ctr.config.NoCgroups { if ctr.config.Spec.Linux == nil { return nil, errors.Wrapf(define.ErrInvalidArg, "must provide Linux namespace configuration in OCI spec when using NoCgroups") } foundPid := false for _, ns := range ctr.config.Spec.Linux.Namespaces { if ns.Type == spec.PIDNamespace { foundPid = true if ns.Path != "" { return nil, errors.Wrapf(define.ErrInvalidArg, "containers not creating CGroups must create a private PID namespace - cannot use another") } break } } if !foundPid { return nil, errors.Wrapf(define.ErrInvalidArg, "containers not creating CGroups must create a private PID namespace") } } // Check CGroup parent sanity, and set it if it was not set. // Only if we're actually configuring CGroups. if !ctr.config.NoCgroups { switch r.config.CgroupManager { case CgroupfsCgroupsManager: if ctr.config.CgroupParent == "" { if pod != nil && pod.config.UsePodCgroup { podCgroup, err := pod.CgroupPath() if err != nil { return nil, errors.Wrapf(err, "error retrieving pod %s cgroup", pod.ID()) } if podCgroup == "" { return nil, errors.Wrapf(define.ErrInternal, "pod %s cgroup is not set", pod.ID()) } ctr.config.CgroupParent = podCgroup } else { ctr.config.CgroupParent = CgroupfsDefaultCgroupParent } } else if strings.HasSuffix(path.Base(ctr.config.CgroupParent), ".slice") { return nil, errors.Wrapf(define.ErrInvalidArg, "systemd slice received as cgroup parent when using cgroupfs") } case SystemdCgroupsManager: if ctr.config.CgroupParent == "" { if pod != nil && pod.config.UsePodCgroup { podCgroup, err := pod.CgroupPath() if err != nil { return nil, errors.Wrapf(err, "error retrieving pod %s cgroup", pod.ID()) } ctr.config.CgroupParent = podCgroup } else if rootless.IsRootless() { ctr.config.CgroupParent = SystemdDefaultRootlessCgroupParent } else { ctr.config.CgroupParent = SystemdDefaultCgroupParent } } else if len(ctr.config.CgroupParent) < 6 || !strings.HasSuffix(path.Base(ctr.config.CgroupParent), ".slice") { return nil, errors.Wrapf(define.ErrInvalidArg, "did not receive systemd slice as cgroup parent when using systemd to manage cgroups") } default: return nil, errors.Wrapf(define.ErrInvalidArg, "unsupported CGroup manager: %s - cannot validate cgroup parent", r.config.CgroupManager) } } if ctr.restoreFromCheckpoint { // Remove information about bind mount // for new container from imported checkpoint g := generate.Generator{Config: ctr.config.Spec} g.RemoveMount("/dev/shm") ctr.config.ShmDir = "" g.RemoveMount("/etc/resolv.conf") g.RemoveMount("/etc/hostname") g.RemoveMount("/etc/hosts") g.RemoveMount("/run/.containerenv") g.RemoveMount("/run/secrets") } // Set up storage for the container if err := ctr.setupStorage(ctx); err != nil { return nil, err } defer func() { if err != nil { if err2 := ctr.teardownStorage(); err2 != nil { logrus.Errorf("Error removing partially-created container root filesystem: %s", err2) } } }() if ctr.config.ConmonPidFile == "" { ctr.config.ConmonPidFile = filepath.Join(ctr.state.RunDir, "conmon.pid") } // Go through named volumes and add them. // If they don't exist they will be created using basic options. // Maintain an array of them - we need to lock them later. ctrNamedVolumes := make([]*Volume, 0, len(ctr.config.NamedVolumes)) for _, vol := range ctr.config.NamedVolumes { // Check if it exists already dbVol, err := r.state.Volume(vol.Name) if err == nil { ctrNamedVolumes = append(ctrNamedVolumes, dbVol) // The volume exists, we're good continue } else if errors.Cause(err) != define.ErrNoSuchVolume { return nil, errors.Wrapf(err, "error retrieving named volume %s for new container", vol.Name) } logrus.Debugf("Creating new volume %s for container", vol.Name) // The volume does not exist, so we need to create it. newVol, err := r.newVolume(ctx, WithVolumeName(vol.Name), withSetCtrSpecific(), WithVolumeUID(ctr.RootUID()), WithVolumeGID(ctr.RootGID())) if err != nil { return nil, errors.Wrapf(err, "error creating named volume %q", vol.Name) } ctrNamedVolumes = append(ctrNamedVolumes, newVol) } if ctr.config.LogPath == "" && ctr.config.LogDriver != JournaldLogging { ctr.config.LogPath = filepath.Join(ctr.config.StaticDir, "ctr.log") } if !MountExists(ctr.config.Spec.Mounts, "/dev/shm") && ctr.config.ShmDir == "" { ctr.config.ShmDir = filepath.Join(ctr.bundlePath(), "shm") if err := os.MkdirAll(ctr.config.ShmDir, 0700); err != nil { if !os.IsExist(err) { return nil, errors.Wrapf(err, "unable to create shm %q dir", ctr.config.ShmDir) } } ctr.config.Mounts = append(ctr.config.Mounts, ctr.config.ShmDir) } // Lock all named volumes we are adding ourself to, to ensure we can't // use a volume being removed. for _, namedVol := range ctrNamedVolumes { toLock := namedVol toLock.lock.Lock() defer toLock.lock.Unlock() } // Add the container to the state // TODO: May be worth looking into recovering from name/ID collisions here if ctr.config.Pod != "" { // Lock the pod to ensure we can't add containers to pods // being removed pod.lock.Lock() defer pod.lock.Unlock() if err := r.state.AddContainerToPod(pod, ctr); err != nil { return nil, err } } else { if err := r.state.AddContainer(ctr); err != nil { return nil, err } } ctr.newContainerEvent(events.Create) return ctr, nil } // RemoveContainer removes the given container // If force is specified, the container will be stopped first // If removeVolume is specified, named volumes used by the container will // be removed also if and only if the container is the sole user // Otherwise, RemoveContainer will return an error if the container is running func (r *Runtime) RemoveContainer(ctx context.Context, c *Container, force bool, removeVolume bool) error { r.lock.Lock() defer r.lock.Unlock() return r.removeContainer(ctx, c, force, removeVolume, false) } // Internal function to remove a container. // Locks the container, but does not lock the runtime. // removePod is used only when removing pods. It instructs Podman to ignore // infra container protections, and *not* remove from the database (as pod // remove will handle that). func (r *Runtime) removeContainer(ctx context.Context, c *Container, force bool, removeVolume bool, removePod bool) error { span, _ := opentracing.StartSpanFromContext(ctx, "removeContainer") span.SetTag("type", "runtime") defer span.Finish() if !c.valid { if ok, _ := r.state.HasContainer(c.ID()); !ok { // Container probably already removed // Or was never in the runtime to begin with return nil } } // We need to lock the pod before we lock the container. // To avoid races around removing a container and the pod it is in. // Don't need to do this in pod removal case - we're evicting the entire // pod. var pod *Pod var err error runtime := c.runtime if c.config.Pod != "" && !removePod { pod, err = r.state.Pod(c.config.Pod) if err != nil { return errors.Wrapf(err, "container %s is in pod %s, but pod cannot be retrieved", c.ID(), pod.ID()) } // Lock the pod while we're removing container pod.lock.Lock() defer pod.lock.Unlock() if err := pod.updatePod(); err != nil { return err } infraID := pod.state.InfraContainerID if c.ID() == infraID { return errors.Errorf("container %s is the infra container of pod %s and cannot be removed without removing the pod", c.ID(), pod.ID()) } } // For pod removal, the container is already locked by the caller if !removePod { c.lock.Lock() defer c.lock.Unlock() } if !r.valid { return define.ErrRuntimeStopped } // Update the container to get current state if err := c.syncContainer(); err != nil { return err } // If we're not force-removing, we need to check if we're in a good // state to remove. if !force { if err := c.checkReadyForRemoval(); err != nil { return err } } if c.state.State == define.ContainerStatePaused { if err := c.ociRuntime.killContainer(c, 9); err != nil { return err } if err := c.unpause(); err != nil { return err } // Need to update container state to make sure we know it's stopped if err := c.waitForExitFileAndSync(); err != nil { return err } } // Check that the container's in a good state to be removed if c.state.State == define.ContainerStateRunning { if err := c.stop(c.StopTimeout()); err != nil { return errors.Wrapf(err, "cannot remove container %s as it could not be stopped", c.ID()) } } // Check that all of our exec sessions have finished if len(c.state.ExecSessions) != 0 { if err := c.ociRuntime.execStopContainer(c, c.StopTimeout()); err != nil { return err } } // Check that no other containers depend on the container. // Only used if not removing a pod - pods guarantee that all // deps will be evicted at the same time. if !removePod { deps, err := r.state.ContainerInUse(c) if err != nil { return err } if len(deps) != 0 { depsStr := strings.Join(deps, ", ") return errors.Wrapf(define.ErrCtrExists, "container %s has dependent containers which must be removed before it: %s", c.ID(), depsStr) } } var cleanupErr error // Remove the container from the state if c.config.Pod != "" { // If we're removing the pod, the container will be evicted // from the state elsewhere if !removePod { if err := r.state.RemoveContainerFromPod(pod, c); err != nil { cleanupErr = err } } } else { if err := r.state.RemoveContainer(c); err != nil { cleanupErr = err } } // Set container as invalid so it can no longer be used c.valid = false // Clean up network namespace, cgroups, mounts if err := c.cleanup(ctx); err != nil { if cleanupErr == nil { cleanupErr = errors.Wrapf(err, "error cleaning up container %s", c.ID()) } else { logrus.Errorf("cleanup network, cgroups, mounts: %v", err) } } // Stop the container's storage if err := c.teardownStorage(); err != nil { if cleanupErr == nil { cleanupErr = err } else { logrus.Errorf("cleanup storage: %v", err) } } // Delete the container. // Not needed in Configured and Exited states, where the container // doesn't exist in the runtime if c.state.State != define.ContainerStateConfigured && c.state.State != define.ContainerStateExited { if err := c.delete(ctx); err != nil { if cleanupErr == nil { cleanupErr = err } else { logrus.Errorf("delete container: %v", err) } } } // Deallocate the container's lock if err := c.lock.Free(); err != nil { if cleanupErr == nil { cleanupErr = errors.Wrapf(err, "error freeing lock for container %s", c.ID()) } else { logrus.Errorf("free container lock: %v", err) } } c.newContainerEvent(events.Remove) if !removeVolume { return cleanupErr } for _, v := range c.config.NamedVolumes { if volume, err := runtime.state.Volume(v.Name); err == nil { if !volume.IsCtrSpecific() { continue } if err := runtime.removeVolume(ctx, volume, false); err != nil && err != define.ErrNoSuchVolume && err != define.ErrVolumeBeingUsed { logrus.Errorf("cleanup volume (%s): %v", v, err) } } } return cleanupErr } // EvictContainer removes the given container partial or full ID or name, and // returns the full ID of the evicted container and any error encountered. // It should be used to remove a container when obtaining a Container struct // pointer has failed. // Running container will not be stopped. // If removeVolume is specified, named volumes used by the container will // be removed also if and only if the container is the sole user. func (r *Runtime) EvictContainer(ctx context.Context, idOrName string, removeVolume bool) (string, error) { r.lock.RLock() defer r.lock.RUnlock() return r.evictContainer(ctx, idOrName, removeVolume) } // evictContainer is the internal function to handle container eviction based // on its partial or full ID or name. // It returns the full ID of the evicted container and any error encountered. // This does not lock the runtime nor the container. // removePod is used only when removing pods. It instructs Podman to ignore // infra container protections, and *not* remove from the database (as pod // remove will handle that). func (r *Runtime) evictContainer(ctx context.Context, idOrName string, removeVolume bool) (string, error) { var err error if !r.valid { return "", define.ErrRuntimeStopped } id, err := r.state.LookupContainerID(idOrName) if err != nil { return "", errors.Wrapf(err, "Failed to find container %q in state", idOrName) } // Error out if the container does not exist in libpod exists, err := r.state.HasContainer(id) if err != nil { return id, err } if !exists { return id, errors.Wrapf(err, "Failed to find container ID %q for eviction", id) } // Re-create a container struct for removal purposes c := new(Container) c.config, err = r.state.GetContainerConfig(id) if err != nil { return id, errors.Wrapf(err, "failed to retrieve config for ctr ID %q", id) } c.state = new(ContainerState) // We need to lock the pod before we lock the container. // To avoid races around removing a container and the pod it is in. // Don't need to do this in pod removal case - we're evicting the entire // pod. var pod *Pod if c.config.Pod != "" { pod, err = r.state.Pod(c.config.Pod) if err != nil { return id, errors.Wrapf(err, "container %s is in pod %s, but pod cannot be retrieved", c.ID(), pod.ID()) } // Lock the pod while we're removing container pod.lock.Lock() defer pod.lock.Unlock() if err := pod.updatePod(); err != nil { return id, err } infraID := pod.state.InfraContainerID if c.ID() == infraID { return id, errors.Errorf("container %s is the infra container of pod %s and cannot be removed without removing the pod", c.ID(), pod.ID()) } } var cleanupErr error // Remove the container from the state if c.config.Pod != "" { // If we're removing the pod, the container will be evicted // from the state elsewhere if err := r.state.RemoveContainerFromPod(pod, c); err != nil { cleanupErr = err } } else { if err := r.state.RemoveContainer(c); err != nil { cleanupErr = err } } // Unmount container mount points for _, mount := range c.config.Mounts { Unmount(mount) } // Remove container from c/storage if err := r.removeStorageContainer(id, true); err != nil { if cleanupErr == nil { cleanupErr = err } } if !removeVolume { return id, cleanupErr } for _, v := range c.config.NamedVolumes { if volume, err := r.state.Volume(v.Name); err == nil { if !volume.IsCtrSpecific() { continue } if err := r.removeVolume(ctx, volume, false); err != nil && err != define.ErrNoSuchVolume && err != define.ErrVolumeBeingUsed { logrus.Errorf("cleanup volume (%s): %v", v, err) } } } return id, cleanupErr } // GetContainer retrieves a container by its ID func (r *Runtime) GetContainer(id string) (*Container, error) { r.lock.RLock() defer r.lock.RUnlock() if !r.valid { return nil, define.ErrRuntimeStopped } return r.state.Container(id) } // HasContainer checks if a container with the given ID is present func (r *Runtime) HasContainer(id string) (bool, error) { r.lock.RLock() defer r.lock.RUnlock() if !r.valid { return false, define.ErrRuntimeStopped } return r.state.HasContainer(id) } // LookupContainer looks up a container by its name or a partial ID // If a partial ID is not unique, an error will be returned func (r *Runtime) LookupContainer(idOrName string) (*Container, error) { r.lock.RLock() defer r.lock.RUnlock() if !r.valid { return nil, define.ErrRuntimeStopped } return r.state.LookupContainer(idOrName) } // GetContainers retrieves all containers from the state // Filters can be provided which will determine what containers are included in // the output. Multiple filters are handled by ANDing their output, so only // containers matching all filters are returned func (r *Runtime) GetContainers(filters ...ContainerFilter) ([]*Container, error) { r.lock.RLock() defer r.lock.RUnlock() if !r.valid { return nil, define.ErrRuntimeStopped } ctrs, err := r.state.AllContainers() if err != nil { return nil, err } ctrsFiltered := make([]*Container, 0, len(ctrs)) for _, ctr := range ctrs { include := true for _, filter := range filters { include = include && filter(ctr) } if include { ctrsFiltered = append(ctrsFiltered, ctr) } } return ctrsFiltered, nil } // GetAllContainers is a helper function for GetContainers func (r *Runtime) GetAllContainers() ([]*Container, error) { return r.state.AllContainers() } // GetRunningContainers is a helper function for GetContainers func (r *Runtime) GetRunningContainers() ([]*Container, error) { running := func(c *Container) bool { state, _ := c.State() return state == define.ContainerStateRunning } return r.GetContainers(running) } // GetContainersByList is a helper function for GetContainers // which takes a []string of container IDs or names func (r *Runtime) GetContainersByList(containers []string) ([]*Container, error) { var ctrs []*Container for _, inputContainer := range containers { ctr, err := r.LookupContainer(inputContainer) if err != nil { return ctrs, errors.Wrapf(err, "unable to lookup container %s", inputContainer) } ctrs = append(ctrs, ctr) } return ctrs, nil } // GetLatestContainer returns a container object of the latest created container. func (r *Runtime) GetLatestContainer() (*Container, error) { lastCreatedIndex := -1 var lastCreatedTime time.Time ctrs, err := r.GetAllContainers() if err != nil { return nil, errors.Wrapf(err, "unable to find latest container") } if len(ctrs) == 0 { return nil, define.ErrNoSuchCtr } for containerIndex, ctr := range ctrs { createdTime := ctr.config.CreatedTime if createdTime.After(lastCreatedTime) { lastCreatedTime = createdTime lastCreatedIndex = containerIndex } } return ctrs[lastCreatedIndex], nil }