package common import ( "fmt" "path/filepath" "strings" "github.com/containers/common/pkg/parse" "github.com/containers/podman/v2/pkg/specgen" "github.com/containers/podman/v2/pkg/util" spec "github.com/opencontainers/runtime-spec/specs-go" "github.com/pkg/errors" ) 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" // TypeDevpts is the type for creating a devpts TypeDevpts = "devpts" ) var ( errDuplicateDest = errors.Errorf("duplicate mount destination") optionArgError = errors.Errorf("must provide an argument for option") noDestError = errors.Errorf("must set volume destination") errInvalidSyntax = errors.Errorf("incorrect mount format: should be --mount type=,[src=,]target=[,options]") ) // Parse all volume-related options in the create config into a set of mounts // and named volumes to add to the container. // Handles --volumes, --mount, and --tmpfs flags. // Does not handle image volumes, init, and --volumes-from flags. // Can also add tmpfs mounts from read-only tmpfs. // TODO: handle options parsing/processing via containers/storage/pkg/mount func parseVolumes(volumeFlag, mountFlag, tmpfsFlag []string, addReadOnlyTmpfs bool) ([]spec.Mount, []*specgen.NamedVolume, []*specgen.OverlayVolume, []*specgen.ImageVolume, error) { // Get mounts from the --mounts flag. unifiedMounts, unifiedVolumes, unifiedImageVolumes, err := getMounts(mountFlag) if err != nil { return nil, nil, nil, nil, err } // Next --volumes flag. volumeMounts, volumeVolumes, overlayVolumes, err := specgen.GenVolumeMounts(volumeFlag) if err != nil { return nil, nil, nil, nil, err } // Next --tmpfs flag. tmpfsMounts, err := getTmpfsMounts(tmpfsFlag) if err != nil { return nil, nil, 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, nil, nil, errors.Wrapf(errDuplicateDest, dest) } unifiedMounts[dest] = mount } for dest, volume := range volumeVolumes { if _, ok := unifiedVolumes[dest]; ok { return nil, nil, nil, nil, errors.Wrapf(errDuplicateDest, dest) } unifiedVolumes[dest] = volume } // Now --tmpfs for dest, tmpfs := range tmpfsMounts { if _, ok := unifiedMounts[dest]; ok { return nil, nil, nil, nil, errors.Wrapf(errDuplicateDest, dest) } unifiedMounts[dest] = tmpfs } // If requested, add tmpfs filesystems for read-only containers. if addReadOnlyTmpfs { readonlyTmpfs := []string{"/tmp", "/var/tmp", "/run"} options := []string{"rw", "rprivate", "nosuid", "nodev", "tmpcopyup"} for _, dest := range readonlyTmpfs { if _, ok := unifiedMounts[dest]; ok { continue } if _, ok := unifiedVolumes[dest]; ok { continue } unifiedMounts[dest] = spec.Mount{ Destination: dest, Type: TypeTmpfs, Source: "tmpfs", Options: options, } } } // Check for conflicts between named volumes, overlay & image volumes, // and mounts allMounts := make(map[string]bool) testAndSet := func(dest string) error { if _, ok := allMounts[dest]; ok { return errors.Wrapf(errDuplicateDest, "conflict at mount destination %v", dest) } allMounts[dest] = true return nil } for dest := range unifiedMounts { if err := testAndSet(dest); err != nil { return nil, nil, nil, nil, err } } for dest := range unifiedVolumes { if err := testAndSet(dest); err != nil { return nil, nil, nil, nil, err } } for dest := range overlayVolumes { if err := testAndSet(dest); err != nil { return nil, nil, nil, nil, err } } for dest := range unifiedImageVolumes { if err := testAndSet(dest); err != nil { return nil, nil, nil, nil, err } } // Final step: maps to arrays finalMounts := make([]spec.Mount, 0, len(unifiedMounts)) for _, mount := range unifiedMounts { if mount.Type == TypeBind { absSrc, err := filepath.Abs(mount.Source) if err != nil { return nil, nil, nil, nil, errors.Wrapf(err, "error getting absolute path of %s", mount.Source) } mount.Source = absSrc } finalMounts = append(finalMounts, mount) } finalVolumes := make([]*specgen.NamedVolume, 0, len(unifiedVolumes)) for _, volume := range unifiedVolumes { finalVolumes = append(finalVolumes, volume) } finalOverlayVolume := make([]*specgen.OverlayVolume, 0) for _, volume := range overlayVolumes { finalOverlayVolume = append(finalOverlayVolume, volume) } finalImageVolumes := make([]*specgen.ImageVolume, 0, len(unifiedImageVolumes)) for _, volume := range unifiedImageVolumes { finalImageVolumes = append(finalImageVolumes, volume) } return finalMounts, finalVolumes, finalOverlayVolume, finalImageVolumes, nil } // findMountType parses the input and extracts the type of the mount type and // the remaining non-type tokens. func findMountType(input string) (mountType string, tokens []string, err error) { // Split by comma, iterate over the slice and look for // "type=$mountType". Everything else is appended to tokens. found := false for _, s := range strings.Split(input, ",") { kv := strings.Split(s, "=") if found || !(len(kv) == 2 && kv[0] == "type") { tokens = append(tokens, s) continue } mountType = kv[1] found = true } if !found { err = errInvalidSyntax } return } // 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 getMounts(mountFlag []string) (map[string]spec.Mount, map[string]*specgen.NamedVolume, map[string]*specgen.ImageVolume, error) { finalMounts := make(map[string]spec.Mount) finalNamedVolumes := make(map[string]*specgen.NamedVolume) finalImageVolumes := make(map[string]*specgen.ImageVolume) for _, mount := range mountFlag { // TODO: Docker defaults to "volume" if no mount type is specified. mountType, tokens, err := findMountType(mount) if err != nil { return nil, nil, nil, err } switch mountType { case TypeBind: mount, err := getBindMount(tokens) if err != nil { return nil, nil, nil, err } if _, ok := finalMounts[mount.Destination]; ok { return nil, nil, nil, errors.Wrapf(errDuplicateDest, mount.Destination) } finalMounts[mount.Destination] = mount case TypeTmpfs: mount, err := getTmpfsMount(tokens) if err != nil { return nil, nil, nil, err } if _, ok := finalMounts[mount.Destination]; ok { return nil, nil, nil, errors.Wrapf(errDuplicateDest, mount.Destination) } finalMounts[mount.Destination] = mount case TypeDevpts: mount, err := getDevptsMount(tokens) if err != nil { return nil, nil, nil, err } if _, ok := finalMounts[mount.Destination]; ok { return nil, nil, nil, errors.Wrapf(errDuplicateDest, mount.Destination) } finalMounts[mount.Destination] = mount case "image": volume, err := getImageVolume(tokens) if err != nil { return nil, nil, nil, err } if _, ok := finalImageVolumes[volume.Destination]; ok { return nil, nil, nil, errors.Wrapf(errDuplicateDest, volume.Destination) } finalImageVolumes[volume.Destination] = volume case "volume": volume, err := getNamedVolume(tokens) if err != nil { return nil, nil, nil, err } if _, ok := finalNamedVolumes[volume.Dest]; ok { return nil, nil, nil, errors.Wrapf(errDuplicateDest, volume.Dest) } finalNamedVolumes[volume.Dest] = volume default: return nil, nil, nil, errors.Errorf("invalid filesystem type %q", mountType) } } return finalMounts, finalNamedVolumes, finalImageVolumes, nil } // Parse a single bind mount entry from the --mount flag. func getBindMount(args []string) (spec.Mount, error) { newMount := spec.Mount{ Type: TypeBind, } var setSource, setDest, setRORW, setSuid, setDev, setExec, setRelabel bool for _, val := range args { kv := strings.SplitN(val, "=", 2) switch kv[0] { case "bind-nonrecursive": newMount.Options = append(newMount.Options, "bind") case "readonly", "ro", "rw": if setRORW { return newMount, errors.Wrapf(optionArgError, "cannot pass 'readonly', 'ro', or 'rw' options more than once") } setRORW = true // Can be formatted as one of: // readonly // readonly=[true|false] // ro // ro=[true|false] // rw // rw=[true|false] if kv[0] == "readonly" { kv[0] = "ro" } switch len(kv) { case 1: newMount.Options = append(newMount.Options, kv[0]) case 2: switch strings.ToLower(kv[1]) { case "true": newMount.Options = append(newMount.Options, kv[0]) case "false": // Set the opposite only for rw // ro's opposite is the default if kv[0] == "rw" { newMount.Options = append(newMount.Options, "ro") } default: return newMount, errors.Wrapf(optionArgError, "'readonly', 'ro', or 'rw' must be set to true or false, instead received %q", kv[1]) } default: return newMount, errors.Wrapf(optionArgError, "badly formatted option %q", val) } case "nosuid", "suid": if setSuid { return newMount, errors.Wrapf(optionArgError, "cannot pass 'nosuid' and 'suid' options more than once") } setSuid = true newMount.Options = append(newMount.Options, kv[0]) case "nodev", "dev": if setDev { return newMount, errors.Wrapf(optionArgError, "cannot pass 'nodev' and 'dev' options more than once") } setDev = true newMount.Options = append(newMount.Options, kv[0]) case "noexec", "exec": if setExec { return newMount, errors.Wrapf(optionArgError, "cannot pass 'noexec' and 'exec' options more than once") } setExec = true newMount.Options = append(newMount.Options, kv[0]) case "shared", "rshared", "private", "rprivate", "slave", "rslave", "unbindable", "runbindable", "Z", "z": newMount.Options = append(newMount.Options, kv[0]) case "bind-propagation": 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 len(kv[1]) == 0 { return newMount, errors.Wrapf(optionArgError, "host directory cannot be empty") } newMount.Source = kv[1] setSource = true case "target", "dst", "destination": if len(kv) == 1 { return newMount, errors.Wrapf(optionArgError, kv[0]) } if err := parse.ValidateVolumeCtrDir(kv[1]); err != nil { return newMount, err } newMount.Destination = filepath.Clean(kv[1]) setDest = true case "relabel": if setRelabel { return newMount, errors.Wrapf(optionArgError, "cannot pass 'relabel' option more than once") } setRelabel = true if len(kv) != 2 { return newMount, errors.Wrapf(util.ErrBadMntOption, "%s mount option must be 'private' or 'shared'", kv[0]) } switch kv[1] { case "private": newMount.Options = append(newMount.Options, "z") case "shared": newMount.Options = append(newMount.Options, "Z") default: return newMount, errors.Wrapf(util.ErrBadMntOption, "%s mount option must be 'private' or 'shared'", kv[0]) } case "consistency": // Often used on MACs and mistakenly on Linux platforms. // Since Docker ignores this option so shall we. continue default: return newMount, errors.Wrapf(util.ErrBadMntOption, kv[0]) } } if !setDest { return newMount, noDestError } if !setSource { newMount.Source = newMount.Destination } options, err := parse.ValidateVolumeOpts(newMount.Options) if err != nil { return newMount, err } newMount.Options = 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, } var setDest, setRORW, setSuid, setDev, setExec, setTmpcopyup bool for _, val := range args { kv := strings.SplitN(val, "=", 2) switch kv[0] { case "tmpcopyup", "notmpcopyup": if setTmpcopyup { return newMount, errors.Wrapf(optionArgError, "cannot pass 'tmpcopyup' and 'notmpcopyup' options more than once") } setTmpcopyup = true newMount.Options = append(newMount.Options, kv[0]) case "ro", "rw": if setRORW { return newMount, errors.Wrapf(optionArgError, "cannot pass 'ro' and 'rw' options more than once") } setRORW = true newMount.Options = append(newMount.Options, kv[0]) case "nosuid", "suid": if setSuid { return newMount, errors.Wrapf(optionArgError, "cannot pass 'nosuid' and 'suid' options more than once") } setSuid = true newMount.Options = append(newMount.Options, kv[0]) case "nodev", "dev": if setDev { return newMount, errors.Wrapf(optionArgError, "cannot pass 'nodev' and 'dev' options more than once") } setDev = true newMount.Options = append(newMount.Options, kv[0]) case "noexec", "exec": if setExec { return newMount, errors.Wrapf(optionArgError, "cannot pass 'noexec' and 'exec' options more than once") } setExec = true newMount.Options = append(newMount.Options, kv[0]) case "tmpfs-mode": 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": 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 := parse.ValidateVolumeCtrDir(kv[1]); err != nil { return newMount, err } newMount.Destination = filepath.Clean(kv[1]) setDest = true case "consistency": // Often used on MACs and mistakenly on Linux platforms. // Since Docker ignores this option so shall we. continue default: return newMount, errors.Wrapf(util.ErrBadMntOption, kv[0]) } } if !setDest { return newMount, noDestError } return newMount, nil } // Parse a single devpts mount entry from the --mount flag func getDevptsMount(args []string) (spec.Mount, error) { newMount := spec.Mount{ Type: TypeDevpts, Source: TypeDevpts, } var setDest bool for _, val := range args { kv := strings.SplitN(val, "=", 2) switch kv[0] { case "target", "dst", "destination": if len(kv) == 1 { return newMount, errors.Wrapf(optionArgError, kv[0]) } if err := parse.ValidateVolumeCtrDir(kv[1]); err != nil { return newMount, err } newMount.Destination = filepath.Clean(kv[1]) setDest = true default: return newMount, errors.Wrapf(util.ErrBadMntOption, 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) (*specgen.NamedVolume, error) { newVolume := new(specgen.NamedVolume) var setSource, setDest, setRORW, setSuid, setDev, setExec bool for _, val := range args { kv := strings.SplitN(val, "=", 2) switch kv[0] { case "ro", "rw": if setRORW { return nil, errors.Wrapf(optionArgError, "cannot pass 'ro' and 'rw' options more than once") } setRORW = true newVolume.Options = append(newVolume.Options, kv[0]) case "nosuid", "suid": if setSuid { return nil, errors.Wrapf(optionArgError, "cannot pass 'nosuid' and 'suid' options more than once") } setSuid = true newVolume.Options = append(newVolume.Options, kv[0]) case "nodev", "dev": if setDev { return nil, errors.Wrapf(optionArgError, "cannot pass 'nodev' and 'dev' options more than once") } setDev = true newVolume.Options = append(newVolume.Options, kv[0]) case "noexec", "exec": if setExec { return nil, errors.Wrapf(optionArgError, "cannot pass 'noexec' and 'exec' options more than once") } setExec = true 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 := parse.ValidateVolumeCtrDir(kv[1]); err != nil { return nil, err } newVolume.Dest = filepath.Clean(kv[1]) setDest = true case "consistency": // Often used on MACs and mistakenly on Linux platforms. // Since Docker ignores this option so shall we. continue default: return nil, errors.Wrapf(util.ErrBadMntOption, kv[0]) } } if !setSource { return nil, errors.Errorf("must set source volume") } if !setDest { return nil, noDestError } return newVolume, nil } // Parse the arguments into an image volume. An image volume is a volume based // on a container image. The container image is first mounted on the host and // is then bind-mounted into the container. An ImageVolume is always mounted // read only. func getImageVolume(args []string) (*specgen.ImageVolume, error) { newVolume := new(specgen.ImageVolume) for _, val := range args { kv := strings.SplitN(val, "=", 2) switch kv[0] { case "src", "source": if len(kv) == 1 { return nil, errors.Wrapf(optionArgError, kv[0]) } newVolume.Source = kv[1] case "target", "dst", "destination": if len(kv) == 1 { return nil, errors.Wrapf(optionArgError, kv[0]) } if err := parse.ValidateVolumeCtrDir(kv[1]); err != nil { return nil, err } newVolume.Destination = filepath.Clean(kv[1]) case "rw", "readwrite": switch kv[1] { case "true": newVolume.ReadWrite = true case "false": // Nothing to do. RO is default. default: return nil, errors.Wrapf(util.ErrBadMntOption, "invalid rw value %q", kv[1]) } case "consistency": // Often used on MACs and mistakenly on Linux platforms. // Since Docker ignores this option so shall we. continue default: return nil, errors.Wrapf(util.ErrBadMntOption, kv[0]) } } if len(newVolume.Source)*len(newVolume.Destination) == 0 { return nil, errors.Errorf("must set source and destination for image volume") } return newVolume, nil } // GetTmpfsMounts creates spec.Mount structs for user-requested tmpfs mounts func getTmpfsMounts(tmpfsFlag []string) (map[string]spec.Mount, error) { m := make(map[string]spec.Mount) for _, i := range tmpfsFlag { // Default options if nothing passed var options []string spliti := strings.Split(i, ":") destPath := spliti[0] if err := parse.ValidateVolumeCtrDir(spliti[0]); err != nil { return nil, err } if len(spliti) > 1 { options = strings.Split(spliti[1], ",") } if _, ok := m[destPath]; ok { return nil, errors.Wrapf(errDuplicateDest, destPath) } mount := spec.Mount{ Destination: filepath.Clean(destPath), Type: string(TypeTmpfs), Options: options, Source: string(TypeTmpfs), } m[destPath] = mount } return m, nil }