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-rw-r--r--pkg/spec/storage.go765
1 files changed, 765 insertions, 0 deletions
diff --git a/pkg/spec/storage.go b/pkg/spec/storage.go
new file mode 100644
index 000000000..7806a8c72
--- /dev/null
+++ b/pkg/spec/storage.go
@@ -0,0 +1,765 @@
+package createconfig
+
+import (
+ "fmt"
+ "os"
+ "path"
+ "path/filepath"
+ "strings"
+
+ "github.com/containers/libpod/libpod"
+ "github.com/containers/storage/pkg/stringid"
+ spec "github.com/opencontainers/runtime-spec/specs-go"
+ "github.com/pkg/errors"
+ "github.com/sirupsen/logrus"
+)
+
+const (
+ // TypeBind is the type for mounting host dir
+ TypeBind = "bind"
+ // TypeVolume is the type for named volumes
+ TypeVolume = "volume"
+ // TypeTmpfs is the type for mounting tmpfs
+ TypeTmpfs = "tmpfs"
+)
+
+var (
+ errDuplicateDest = errors.Errorf("duplicate mount destination")
+ badOptionError = errors.Errorf("invalid mount option")
+ optionArgError = errors.Errorf("must provide an argument for option")
+ noDestError = errors.Errorf("must set volume destination")
+)
+
+// Parse all volume-related options in the create config into a set of mounts
+// and named volumes to add to the container.
+// Handles --volumes-from, --volumes, --tmpfs, --init, and --init-path flags.
+// TODO: Named volume options - should we default to rprivate? It bakes into a
+// bind mount under the hood...
+// TODO: Tmpfs options - we should probably check user-given ones, provide sane
+// defaults even if the user provides a few...
+func (config *CreateConfig) parseVolumes(runtime *libpod.Runtime) ([]spec.Mount, []*libpod.ContainerNamedVolume, error) {
+ // Add image volumes.
+ baseMounts, baseVolumes, err := config.getImageVolumes()
+ if err != nil {
+ return nil, nil, err
+ }
+
+ // Add --volumes-from.
+ // Overrides image volumes unconditionally.
+ vFromMounts, vFromVolumes, err := config.getVolumesFrom(runtime)
+ if err != nil {
+ return nil, nil, err
+ }
+ for dest, mount := range vFromMounts {
+ baseMounts[dest] = mount
+ }
+ for dest, volume := range vFromVolumes {
+ baseVolumes[dest] = volume
+ }
+
+ // Next mounts from the --mounts flag.
+ // Do not override yet.
+ unifiedMounts, unifiedVolumes, err := config.getMounts()
+ if err != nil {
+ return nil, nil, err
+ }
+
+ // Next --volumes flag.
+ // Do not override yet.
+ volumeMounts, volumeVolumes, err := config.getVolumeMounts()
+ if err != nil {
+ return nil, nil, err
+ }
+
+ // Next --tmpfs flag.
+ // Do not override yet.
+ tmpfsMounts, err := config.getTmpfsMounts()
+ if err != nil {
+ return nil, nil, err
+ }
+
+ // Unify mounts from --mount, --volume, --tmpfs.
+ // Start with --volume.
+ for dest, mount := range volumeMounts {
+ if _, ok := unifiedMounts[dest]; ok {
+ return nil, nil, errors.Wrapf(errDuplicateDest, dest)
+ }
+ unifiedMounts[dest] = mount
+ }
+ for dest, volume := range volumeVolumes {
+ if _, ok := unifiedVolumes[dest]; ok {
+ return nil, nil, errors.Wrapf(errDuplicateDest, dest)
+ }
+ unifiedVolumes[dest] = volume
+ }
+ // Now --tmpfs
+ for dest, tmpfs := range tmpfsMounts {
+ if _, ok := unifiedMounts[dest]; ok {
+ return nil, nil, errors.Wrapf(errDuplicateDest, dest)
+ }
+ unifiedMounts[dest] = tmpfs
+ }
+
+ // If requested, add container init binary
+ if config.Init {
+ initPath := config.InitPath
+ if initPath == "" {
+ rtc, err := runtime.GetConfig()
+ if err != nil {
+ return nil, nil, err
+ }
+ initPath = rtc.InitPath
+ }
+ initMount, err := config.addContainerInitBinary(initPath)
+ if err != nil {
+ return nil, nil, err
+ }
+ if _, ok := unifiedMounts[initMount.Destination]; ok {
+ return nil, nil, errors.Wrapf(errDuplicateDest, "conflict with mount added by --init to %q", initMount.Destination)
+ }
+ unifiedMounts[initMount.Destination] = initMount
+ }
+
+ // Supercede volumes-from/image volumes with unified volumes from above.
+ // This is an unconditional replacement.
+ for dest, mount := range unifiedMounts {
+ baseMounts[dest] = mount
+ }
+ for dest, volume := range unifiedVolumes {
+ baseVolumes[dest] = volume
+ }
+
+ // TODO: Allow an explicit list of named volumes and spec mounts in the
+ // createconfig. Podman doesn't need them, but other libpod consumers
+ // might want them.
+
+ // Final step: maps to arrays
+ finalMounts := make([]spec.Mount, 0, len(baseMounts))
+ for _, mount := range baseMounts {
+ finalMounts = append(finalMounts, mount)
+ }
+ finalVolumes := make([]*libpod.ContainerNamedVolume, 0, len(baseVolumes))
+ for _, volume := range baseVolumes {
+ finalVolumes = append(finalVolumes, volume)
+ }
+
+ return finalMounts, finalVolumes, nil
+}
+
+// Parse volumes from - a set of containers whose volumes we will mount in.
+// Grab the containers, retrieve any user-created spec mounts and all named
+// volumes, and return a list of them.
+// Conflicts are resolved simply - the last container specified wins.
+// Container names may be suffixed by mount options after a colon.
+func (config *CreateConfig) getVolumesFrom(runtime *libpod.Runtime) (map[string]spec.Mount, map[string]*libpod.ContainerNamedVolume, error) {
+ // TODO: This can probably be disabled now
+ if os.Geteuid() != 0 {
+ return nil, nil, nil
+ }
+
+ // Both of these are maps of mount destination to mount type.
+ // We ensure that each destination is only mounted to once in this way.
+ // We tiebreak only within each category; we'll let libpod tiebreak
+ // between mounts and named volumes.
+ // TODO: Should we unmount subtree mounts? E.g., if /tmp/ is mounted by
+ // one mount, and we already have /tmp/a and /tmp/b, should we remove
+ // the /tmp/a and /tmp/b mounts in favor of the more general /tmp?
+ finalMounts := make(map[string]spec.Mount)
+ finalNamedVolumes := make(map[string]*libpod.ContainerNamedVolume)
+
+ for _, vol := range config.VolumesFrom {
+ options := []string{}
+ // TODO: now that container names may contain colons this is no
+ // longer safe.
+ // I don't know if there's much we can do here...
+ splitVol := strings.SplitN(vol, ":", 2)
+ if len(splitVol) == 2 {
+ if strings.Contains(splitVol[1], "Z") ||
+ strings.Contains(splitVol[1], "private") ||
+ strings.Contains(splitVol[1], "slave") ||
+ strings.Contains(splitVol[1], "shared") {
+ return nil, nil, errors.Errorf("invalid options %q, can only specify 'ro', 'rw', and 'z", splitVol[1])
+ }
+ if err := ValidateVolumeOpts(splitVol[1]); err != nil {
+ return nil, nil, err
+ }
+ options = strings.Split(splitVol[1], ",")
+ }
+ ctr, err := runtime.LookupContainer(splitVol[0])
+ if err != nil {
+ return nil, nil, errors.Wrapf(err, "error looking up container %q for volumes-from", splitVol[0])
+ }
+
+ logrus.Debugf("Adding volumes from container %s", ctr.ID())
+
+ // Look up the container's user volumes. This gets us the
+ // destinations of all mounts the user added to the container.
+ userVolumesArr := ctr.UserVolumes()
+
+ // We're going to need to access them a lot, so convert to a map
+ // to reduce looping.
+ // We'll also use the map to indicate if we missed any volumes along the way.
+ userVolumes := make(map[string]bool)
+ for _, dest := range userVolumesArr {
+ userVolumes[dest] = false
+ }
+
+ // Now we get the container's spec and loop through its volumes
+ // and append them in if we can find them.
+ spec := ctr.Spec()
+ if spec == nil {
+ return nil, nil, errors.Errorf("error retrieving container %s spec for volumes-from", ctr.ID())
+ }
+ for _, mnt := range spec.Mounts {
+ if mnt.Type != TypeBind {
+ continue
+ }
+ if _, exists := userVolumes[mnt.Destination]; exists {
+ userVolumes[mnt.Destination] = true
+
+ if len(options) != 0 {
+ mnt.Options = options
+ }
+
+ if _, ok := finalMounts[mnt.Destination]; ok {
+ logrus.Debugf("Overriding mount to %s with new mount from container %s", mnt.Destination, ctr.ID())
+ }
+ finalMounts[mnt.Destination] = mnt
+ }
+ }
+
+ // We're done with the spec mounts. Add named volumes.
+ // Add these unconditionally - none of them are automatically
+ // part of the container, as some spec mounts are.
+ namedVolumes := ctr.NamedVolumes()
+ for _, namedVol := range namedVolumes {
+ if _, exists := userVolumes[namedVol.Dest]; exists {
+ userVolumes[namedVol.Dest] = true
+ }
+
+ if len(options) != 0 {
+ namedVol.Options = options
+ }
+
+ if _, ok := finalMounts[namedVol.Dest]; ok {
+ logrus.Debugf("Overriding named volume mount to %s with new named volume from container %s", namedVol.Dest, ctr.ID())
+ }
+ finalNamedVolumes[namedVol.Dest] = namedVol
+ }
+
+ // Check if we missed any volumes
+ for volDest, found := range userVolumes {
+ if !found {
+ logrus.Warnf("Unable to match volume %s from container %s for volumes-from", volDest, ctr.ID())
+ }
+ }
+ }
+
+ return finalMounts, finalNamedVolumes, nil
+}
+
+// getMounts takes user-provided input from the --mount flag and creates OCI
+// spec mounts and Libpod named volumes.
+// podman run --mount type=bind,src=/etc/resolv.conf,target=/etc/resolv.conf ...
+// podman run --mount type=tmpfs,target=/dev/shm ...
+// podman run --mount type=volume,source=test-volume, ...
+func (config *CreateConfig) getMounts() (map[string]spec.Mount, map[string]*libpod.ContainerNamedVolume, error) {
+ finalMounts := make(map[string]spec.Mount)
+ finalNamedVolumes := make(map[string]*libpod.ContainerNamedVolume)
+
+ errInvalidSyntax := errors.Errorf("incorrect mount format: should be --mount type=<bind|tmpfs|volume>,[src=<host-dir|volume-name>,]target=<ctr-dir>[,options]")
+
+ // TODO(vrothberg): the manual parsing can be replaced with a regular expression
+ // to allow a more robust parsing of the mount format and to give
+ // precise errors regarding supported format versus suppored options.
+ for _, mount := range config.MountsFlag {
+ arr := strings.SplitN(mount, ",", 2)
+ if len(arr) < 2 {
+ return nil, nil, errors.Wrapf(errInvalidSyntax, "%q", mount)
+ }
+ kv := strings.Split(arr[0], "=")
+ // TODO: type is not explicitly required in Docker.
+ // If not specified, it defaults to "volume".
+ if len(kv) != 2 || kv[0] != "type" {
+ return nil, nil, errors.Wrapf(errInvalidSyntax, "%q", mount)
+ }
+
+ tokens := strings.Split(arr[1], ",")
+ switch kv[1] {
+ case TypeBind:
+ mount, err := getBindMount(tokens)
+ if err != nil {
+ return nil, nil, err
+ }
+ if _, ok := finalMounts[mount.Destination]; ok {
+ return nil, nil, errors.Wrapf(errDuplicateDest, mount.Destination)
+ }
+ finalMounts[mount.Destination] = mount
+ case TypeTmpfs:
+ mount, err := getTmpfsMount(tokens)
+ if err != nil {
+ return nil, nil, err
+ }
+ if _, ok := finalMounts[mount.Destination]; ok {
+ return nil, nil, errors.Wrapf(errDuplicateDest, mount.Destination)
+ }
+ finalMounts[mount.Destination] = mount
+ case "volume":
+ volume, err := getNamedVolume(tokens)
+ if err != nil {
+ return nil, nil, err
+ }
+ if _, ok := finalNamedVolumes[volume.Dest]; ok {
+ return nil, nil, errors.Wrapf(errDuplicateDest, volume.Dest)
+ }
+ finalNamedVolumes[volume.Dest] = volume
+ default:
+ return nil, nil, errors.Errorf("invalid fylesystem type %q", kv[1])
+ }
+ }
+
+ return finalMounts, finalNamedVolumes, nil
+}
+
+// Parse a single bind mount entry from the --mount flag.
+func getBindMount(args []string) (spec.Mount, error) {
+ newMount := spec.Mount{
+ Type: TypeBind,
+ }
+
+ setSource := false
+ setDest := false
+
+ for _, val := range args {
+ kv := strings.Split(val, "=")
+ switch kv[0] {
+ case "ro", "nosuid", "nodev", "noexec":
+ // TODO: detect duplication of these options
+ newMount.Options = append(newMount.Options, kv[0])
+ case "shared", "rshared", "private", "rprivate", "slave", "rslave", "Z", "z":
+ // TODO: detect duplicate mount propagation options
+ newMount.Options = append(newMount.Options, kv[0])
+ case "bind-propagation":
+ // TODO: this should conflict with the mount propagation
+ // options above.
+ if len(kv) == 1 {
+ return newMount, errors.Wrapf(optionArgError, kv[0])
+ }
+ newMount.Options = append(newMount.Options, kv[1])
+ case "src", "source":
+ if len(kv) == 1 {
+ return newMount, errors.Wrapf(optionArgError, kv[0])
+ }
+ if err := ValidateVolumeHostDir(kv[1]); err != nil {
+ return newMount, err
+ }
+ newMount.Source = kv[1]
+ setSource = true
+ case "target", "dst", "destination":
+ if len(kv) == 1 {
+ return newMount, errors.Wrapf(optionArgError, kv[0])
+ }
+ if err := ValidateVolumeCtrDir(kv[1]); err != nil {
+ return newMount, err
+ }
+ newMount.Destination = kv[1]
+ setDest = true
+ default:
+ return newMount, errors.Wrapf(badOptionError, kv[0])
+ }
+ }
+
+ if !setDest {
+ return newMount, noDestError
+ }
+
+ if !setSource {
+ newMount.Source = newMount.Destination
+ }
+
+ // Process options
+ newMount.Options = processOptions(newMount.Options)
+
+ return newMount, nil
+}
+
+// Parse a single tmpfs mount entry from the --mount flag
+func getTmpfsMount(args []string) (spec.Mount, error) {
+ newMount := spec.Mount{
+ Type: TypeTmpfs,
+ Source: TypeTmpfs,
+ }
+
+ setDest := false
+
+ for _, val := range args {
+ kv := strings.Split(val, "=")
+ switch kv[0] {
+ case "ro", "nosuid", "nodev", "noexec":
+ // TODO: detect duplication of these options
+ newMount.Options = append(newMount.Options, kv[0])
+ case "tmpfs-mode":
+ // TODO: detect duplicate modes
+ if len(kv) == 1 {
+ return newMount, errors.Wrapf(optionArgError, kv[0])
+ }
+ newMount.Options = append(newMount.Options, fmt.Sprintf("mode=%s", kv[1]))
+ case "tmpfs-size":
+ // TODO: detect duplicate sizes
+ if len(kv) == 1 {
+ return newMount, errors.Wrapf(optionArgError, kv[0])
+ }
+ newMount.Options = append(newMount.Options, fmt.Sprintf("size=%s", kv[1]))
+ case "src", "source":
+ return newMount, errors.Errorf("source is not supported with tmpfs mounts")
+ case "target", "dst", "destination":
+ if len(kv) == 1 {
+ return newMount, errors.Wrapf(optionArgError, kv[0])
+ }
+ if err := ValidateVolumeCtrDir(kv[1]); err != nil {
+ return newMount, err
+ }
+ newMount.Destination = kv[1]
+ setDest = true
+ default:
+ return newMount, errors.Wrapf(badOptionError, kv[0])
+ }
+ }
+
+ if !setDest {
+ return newMount, noDestError
+ }
+
+ return newMount, nil
+}
+
+// Parse a single volume mount entry from the --mount flag.
+// Note that the volume-label option for named volumes is currently NOT supported.
+// TODO: add support for --volume-label
+func getNamedVolume(args []string) (*libpod.ContainerNamedVolume, error) {
+ newVolume := new(libpod.ContainerNamedVolume)
+
+ setSource := false
+ setDest := false
+
+ for _, val := range args {
+ kv := strings.Split(val, "=")
+ switch kv[0] {
+ case "ro", "nosuid", "nodev", "noexec":
+ // TODO: detect duplication of these options
+ newVolume.Options = append(newVolume.Options, kv[0])
+ case "volume-label":
+ return nil, errors.Errorf("the --volume-label option is not presently implemented")
+ case "src", "source":
+ if len(kv) == 1 {
+ return nil, errors.Wrapf(optionArgError, kv[0])
+ }
+ newVolume.Name = kv[1]
+ setSource = true
+ case "target", "dst", "destination":
+ if len(kv) == 1 {
+ return nil, errors.Wrapf(optionArgError, kv[0])
+ }
+ if err := ValidateVolumeCtrDir(kv[1]); err != nil {
+ return nil, err
+ }
+ newVolume.Dest = kv[1]
+ setDest = true
+ default:
+ return nil, errors.Wrapf(badOptionError, kv[0])
+ }
+ }
+
+ if !setSource {
+ return nil, errors.Errorf("must set source volume")
+ }
+ if !setDest {
+ return nil, noDestError
+ }
+
+ return newVolume, nil
+}
+
+// ValidateVolumeHostDir validates a volume mount's source directory
+func ValidateVolumeHostDir(hostDir string) error {
+ if len(hostDir) == 0 {
+ return errors.Errorf("host directory cannot be empty")
+ }
+ if filepath.IsAbs(hostDir) {
+ if _, err := os.Stat(hostDir); err != nil {
+ return errors.Wrapf(err, "error checking path %q", hostDir)
+ }
+ }
+ // If hostDir is not an absolute path, that means the user wants to create a
+ // named volume. This will be done later on in the code.
+ return nil
+}
+
+// ValidateVolumeCtrDir validates a volume mount's destination directory.
+func ValidateVolumeCtrDir(ctrDir string) error {
+ if len(ctrDir) == 0 {
+ return errors.Errorf("container directory cannot be empty")
+ }
+ if !filepath.IsAbs(ctrDir) {
+ return errors.Errorf("invalid container path %q, must be an absolute path", ctrDir)
+ }
+ return nil
+}
+
+// ValidateVolumeOpts validates a volume's options
+func ValidateVolumeOpts(option string) error {
+ var foundRootPropagation, foundRWRO, foundLabelChange int
+ options := strings.Split(option, ",")
+ for _, opt := range options {
+ switch opt {
+ case "rw", "ro":
+ foundRWRO++
+ if foundRWRO > 1 {
+ return errors.Errorf("invalid options %q, can only specify 1 'rw' or 'ro' option", option)
+ }
+ case "z", "Z":
+ foundLabelChange++
+ if foundLabelChange > 1 {
+ return errors.Errorf("invalid options %q, can only specify 1 'z' or 'Z' option", option)
+ }
+ case "private", "rprivate", "shared", "rshared", "slave", "rslave":
+ foundRootPropagation++
+ if foundRootPropagation > 1 {
+ return errors.Errorf("invalid options %q, can only specify 1 '[r]shared', '[r]private' or '[r]slave' option", option)
+ }
+ default:
+ return errors.Errorf("invalid option type %q", option)
+ }
+ }
+ return nil
+}
+
+// GetVolumeMounts takes user provided input for bind mounts and creates Mount structs
+func (config *CreateConfig) getVolumeMounts() (map[string]spec.Mount, map[string]*libpod.ContainerNamedVolume, error) {
+ mounts := make(map[string]spec.Mount)
+ volumes := make(map[string]*libpod.ContainerNamedVolume)
+
+ volumeFormatErr := errors.Errorf("incorrect volume format, should be host-dir:ctr-dir[:option]")
+
+ for _, vol := range config.Volumes {
+ var (
+ options []string
+ src string
+ dest string
+ )
+
+ splitVol := strings.Split(vol, ":")
+ if len(splitVol) > 3 {
+ return nil, nil, errors.Wrapf(volumeFormatErr, vol)
+ }
+
+ src = splitVol[0]
+ if len(splitVol) == 1 {
+ dest = src
+ } else if len(splitVol) > 1 {
+ dest = splitVol[1]
+ }
+ if len(splitVol) > 2 {
+ if err := ValidateVolumeOpts(splitVol[2]); err != nil {
+ return nil, nil, err
+ }
+ options = strings.Split(splitVol[2], ",")
+ }
+
+ if err := ValidateVolumeHostDir(src); err != nil {
+ return nil, nil, err
+ }
+ if err := ValidateVolumeCtrDir(dest); err != nil {
+ return nil, nil, err
+ }
+
+ if strings.HasPrefix(src, "/") || strings.HasPrefix(src, ".") {
+ // This is not a named volume
+ newMount := spec.Mount{
+ Destination: dest,
+ Type: string(TypeBind),
+ Source: src,
+ Options: processOptions(options),
+ }
+ if _, ok := mounts[newMount.Destination]; ok {
+ return nil, nil, errors.Wrapf(errDuplicateDest, newMount.Destination)
+ }
+ mounts[newMount.Destination] = newMount
+ } else {
+ // This is a named volume
+ newNamedVol := new(libpod.ContainerNamedVolume)
+ newNamedVol.Name = src
+ newNamedVol.Dest = dest
+ newNamedVol.Options = options
+
+ if _, ok := volumes[newNamedVol.Dest]; ok {
+ return nil, nil, errors.Wrapf(errDuplicateDest, newNamedVol.Dest)
+ }
+ volumes[newNamedVol.Dest] = newNamedVol
+ }
+
+ logrus.Debugf("User mount %s:%s options %v", src, dest, options)
+ }
+
+ return mounts, volumes, nil
+}
+
+// Get mounts for container's image volumes
+func (config *CreateConfig) getImageVolumes() (map[string]spec.Mount, map[string]*libpod.ContainerNamedVolume, error) {
+ mounts := make(map[string]spec.Mount)
+ volumes := make(map[string]*libpod.ContainerNamedVolume)
+
+ if config.ImageVolumeType == "ignore" {
+ return mounts, volumes, nil
+ }
+
+ for vol := range config.BuiltinImgVolumes {
+ if config.ImageVolumeType == "tmpfs" {
+ // Tmpfs image volumes are handled as mounts
+ mount := spec.Mount{
+ Destination: vol,
+ Source: TypeTmpfs,
+ Type: TypeTmpfs,
+ Options: []string{"rprivate", "rw", "nodev"},
+ }
+ mounts[vol] = mount
+ } else {
+ namedVolume := new(libpod.ContainerNamedVolume)
+ namedVolume.Name = stringid.GenerateNonCryptoID()
+ namedVolume.Options = []string{"rprivate", "rw", "nodev"}
+ namedVolume.Dest = vol
+ volumes[vol] = namedVolume
+ }
+ }
+
+ return mounts, volumes, nil
+}
+
+// GetTmpfsMounts creates spec.Mount structs for user-requested tmpfs mounts
+func (config *CreateConfig) getTmpfsMounts() (map[string]spec.Mount, error) {
+ m := make(map[string]spec.Mount)
+ for _, i := range config.Tmpfs {
+ // Default options if nothing passed
+ options := []string{"rprivate", "rw", "noexec", "nosuid", "nodev", "size=65536k"}
+ spliti := strings.Split(i, ":")
+ destPath := spliti[0]
+ if len(spliti) > 1 {
+ options = strings.Split(spliti[1], ",")
+ }
+
+ if _, ok := m[destPath]; ok {
+ return nil, errors.Wrapf(errDuplicateDest, destPath)
+ }
+
+ // TODO: Do we want to set some default options if the user
+ // passed options?
+ // TODO: should we validate the options passed in?
+ mount := spec.Mount{
+ Destination: destPath,
+ Type: string(TypeTmpfs),
+ Options: options,
+ Source: string(TypeTmpfs),
+ }
+ m[destPath] = mount
+ }
+ return m, nil
+}
+
+// AddContainerInitBinary adds the init binary specified by path iff the
+// container will run in a private PID namespace that is not shared with the
+// host or another pre-existing container, where an init-like process is
+// already running.
+//
+// Note that AddContainerInitBinary prepends "/dev/init" "--" to the command
+// to execute the bind-mounted binary as PID 1.
+func (config *CreateConfig) addContainerInitBinary(path string) (spec.Mount, error) {
+ mount := spec.Mount{
+ Destination: "/dev/init",
+ Type: TypeBind,
+ Source: path,
+ Options: []string{TypeBind, "ro"},
+ }
+
+ if path == "" {
+ return mount, fmt.Errorf("please specify a path to the container-init binary")
+ }
+ if !config.PidMode.IsPrivate() {
+ return mount, fmt.Errorf("cannot add init binary as PID 1 (PID namespace isn't private)")
+ }
+ if config.Systemd {
+ return mount, fmt.Errorf("cannot use container-init binary with systemd")
+ }
+ if _, err := os.Stat(path); os.IsNotExist(err) {
+ return mount, errors.Wrap(err, "container-init binary not found on the host")
+ }
+ config.Command = append([]string{"/dev/init", "--"}, config.Command...)
+ return mount, nil
+}
+
+// Handle options for volume mounts
+func processOptions(options []string) []string {
+ var (
+ foundrw, foundro bool
+ rootProp string
+ )
+ options = append(options, "rbind")
+ for _, opt := range options {
+ switch opt {
+ case "rw":
+ foundrw = true
+ case "ro":
+ foundro = true
+ case "private", "rprivate", "slave", "rslave", "shared", "rshared":
+ rootProp = opt
+ }
+ }
+ if !foundrw && !foundro {
+ options = append(options, "rw")
+ }
+ if rootProp == "" {
+ options = append(options, "rprivate")
+ }
+ return options
+}
+
+func supercedeUserMounts(mounts []spec.Mount, configMount []spec.Mount) []spec.Mount {
+ if len(mounts) > 0 {
+ // If we have overlappings mounts, remove them from the spec in favor of
+ // the user-added volume mounts
+ destinations := make(map[string]bool)
+ for _, mount := range mounts {
+ destinations[path.Clean(mount.Destination)] = true
+ }
+ // Copy all mounts from spec to defaultMounts, except for
+ // - mounts overridden by a user supplied mount;
+ // - all mounts under /dev if a user supplied /dev is present;
+ mountDev := destinations["/dev"]
+ for _, mount := range configMount {
+ if _, ok := destinations[path.Clean(mount.Destination)]; !ok {
+ if mountDev && strings.HasPrefix(mount.Destination, "/dev/") {
+ // filter out everything under /dev if /dev is user-mounted
+ continue
+ }
+
+ logrus.Debugf("Adding mount %s", mount.Destination)
+ mounts = append(mounts, mount)
+ }
+ }
+ return mounts
+ }
+ return configMount
+}
+
+// Ensure mount options on all mounts are correct
+func initFSMounts(inputMounts []spec.Mount) []spec.Mount {
+ var mounts []spec.Mount
+ for _, m := range inputMounts {
+ m.Options = processOptions(m.Options)
+ if m.Type == "tmpfs" {
+ m.Options = append(m.Options, "tmpcopyup")
+ } else {
+ mounts = append(mounts, m)
+ }
+ }
+ return mounts
+}
generated by cgit v1.2.3-54-g00ecf (git 2.39.0) at 2024-11-16 11:18:49 +0000