blob: 8c3ba00f0754b5b2433be915330da09492ed08f7 [file] [log] [blame]
// +build linux
// Package specconv implements conversion of specifications to libcontainer
// configurations
package specconv
import (
"fmt"
"os"
"path/filepath"
"strings"
"time"
"github.com/opencontainers/runc/libcontainer/configs"
"github.com/opencontainers/runc/libcontainer/seccomp"
libcontainerUtils "github.com/opencontainers/runc/libcontainer/utils"
"github.com/opencontainers/runtime-spec/specs-go"
"golang.org/x/sys/unix"
)
const wildcard = -1
var namespaceMapping = map[specs.LinuxNamespaceType]configs.NamespaceType{
specs.PIDNamespace: configs.NEWPID,
specs.NetworkNamespace: configs.NEWNET,
specs.MountNamespace: configs.NEWNS,
specs.UserNamespace: configs.NEWUSER,
specs.IPCNamespace: configs.NEWIPC,
specs.UTSNamespace: configs.NEWUTS,
}
var mountPropagationMapping = map[string]int{
"rprivate": unix.MS_PRIVATE | unix.MS_REC,
"private": unix.MS_PRIVATE,
"rslave": unix.MS_SLAVE | unix.MS_REC,
"slave": unix.MS_SLAVE,
"rshared": unix.MS_SHARED | unix.MS_REC,
"shared": unix.MS_SHARED,
"": unix.MS_PRIVATE | unix.MS_REC,
}
var allowedDevices = []*configs.Device{
// allow mknod for any device
{
Type: 'c',
Major: wildcard,
Minor: wildcard,
Permissions: "m",
Allow: true,
},
{
Type: 'b',
Major: wildcard,
Minor: wildcard,
Permissions: "m",
Allow: true,
},
{
Type: 'c',
Path: "/dev/null",
Major: 1,
Minor: 3,
Permissions: "rwm",
Allow: true,
},
{
Type: 'c',
Path: "/dev/random",
Major: 1,
Minor: 8,
Permissions: "rwm",
Allow: true,
},
{
Type: 'c',
Path: "/dev/full",
Major: 1,
Minor: 7,
Permissions: "rwm",
Allow: true,
},
{
Type: 'c',
Path: "/dev/tty",
Major: 5,
Minor: 0,
Permissions: "rwm",
Allow: true,
},
{
Type: 'c',
Path: "/dev/zero",
Major: 1,
Minor: 5,
Permissions: "rwm",
Allow: true,
},
{
Type: 'c',
Path: "/dev/urandom",
Major: 1,
Minor: 9,
Permissions: "rwm",
Allow: true,
},
{
Path: "/dev/console",
Type: 'c',
Major: 5,
Minor: 1,
Permissions: "rwm",
Allow: true,
},
// /dev/pts/ - pts namespaces are "coming soon"
{
Path: "",
Type: 'c',
Major: 136,
Minor: wildcard,
Permissions: "rwm",
Allow: true,
},
{
Path: "",
Type: 'c',
Major: 5,
Minor: 2,
Permissions: "rwm",
Allow: true,
},
// tuntap
{
Path: "",
Type: 'c',
Major: 10,
Minor: 200,
Permissions: "rwm",
Allow: true,
},
}
type CreateOpts struct {
CgroupName string
UseSystemdCgroup bool
NoPivotRoot bool
NoNewKeyring bool
Spec *specs.Spec
Rootless bool
}
// CreateLibcontainerConfig creates a new libcontainer configuration from a
// given specification and a cgroup name
func CreateLibcontainerConfig(opts *CreateOpts) (*configs.Config, error) {
// runc's cwd will always be the bundle path
rcwd, err := os.Getwd()
if err != nil {
return nil, err
}
cwd, err := filepath.Abs(rcwd)
if err != nil {
return nil, err
}
spec := opts.Spec
if spec.Root == nil {
return nil, fmt.Errorf("Root must be specified")
}
rootfsPath := spec.Root.Path
if !filepath.IsAbs(rootfsPath) {
rootfsPath = filepath.Join(cwd, rootfsPath)
}
labels := []string{}
for k, v := range spec.Annotations {
labels = append(labels, fmt.Sprintf("%s=%s", k, v))
}
config := &configs.Config{
Rootfs: rootfsPath,
NoPivotRoot: opts.NoPivotRoot,
Readonlyfs: spec.Root.Readonly,
Hostname: spec.Hostname,
Labels: append(labels, fmt.Sprintf("bundle=%s", cwd)),
NoNewKeyring: opts.NoNewKeyring,
Rootless: opts.Rootless,
}
exists := false
if config.Namespaces.Contains(configs.NEWNET) {
config.Networks = []*configs.Network{
{
Type: "loopback",
},
}
}
for _, m := range spec.Mounts {
config.Mounts = append(config.Mounts, createLibcontainerMount(cwd, m))
}
if err := createDevices(spec, config); err != nil {
return nil, err
}
if err := setupUserNamespace(spec, config); err != nil {
return nil, err
}
c, err := createCgroupConfig(opts)
if err != nil {
return nil, err
}
config.Cgroups = c
// set linux-specific config
if spec.Linux != nil {
if config.RootPropagation, exists = mountPropagationMapping[spec.Linux.RootfsPropagation]; !exists {
return nil, fmt.Errorf("rootfsPropagation=%v is not supported", spec.Linux.RootfsPropagation)
}
for _, ns := range spec.Linux.Namespaces {
t, exists := namespaceMapping[ns.Type]
if !exists {
return nil, fmt.Errorf("namespace %q does not exist", ns)
}
if config.Namespaces.Contains(t) {
return nil, fmt.Errorf("malformed spec file: duplicated ns %q", ns)
}
config.Namespaces.Add(t, ns.Path)
}
config.MaskPaths = spec.Linux.MaskedPaths
config.ReadonlyPaths = spec.Linux.ReadonlyPaths
config.MountLabel = spec.Linux.MountLabel
config.Sysctl = spec.Linux.Sysctl
if spec.Linux.Seccomp != nil {
seccomp, err := setupSeccomp(spec.Linux.Seccomp)
if err != nil {
return nil, err
}
config.Seccomp = seccomp
}
}
if spec.Process.SelinuxLabel != "" {
config.ProcessLabel = spec.Process.SelinuxLabel
}
if spec.Process != nil && spec.Process.OOMScoreAdj != nil {
config.OomScoreAdj = *spec.Process.OOMScoreAdj
}
if spec.Process.Capabilities != nil {
config.Capabilities = &configs.Capabilities{
Bounding: spec.Process.Capabilities.Bounding,
Effective: spec.Process.Capabilities.Effective,
Permitted: spec.Process.Capabilities.Permitted,
Inheritable: spec.Process.Capabilities.Inheritable,
Ambient: spec.Process.Capabilities.Ambient,
}
}
createHooks(spec, config)
config.Version = specs.Version
return config, nil
}
func createLibcontainerMount(cwd string, m specs.Mount) *configs.Mount {
flags, pgflags, data, ext := parseMountOptions(m.Options)
source := m.Source
if m.Type == "bind" {
if !filepath.IsAbs(source) {
source = filepath.Join(cwd, m.Source)
}
}
return &configs.Mount{
Device: m.Type,
Source: source,
Destination: m.Destination,
Data: data,
Flags: flags,
PropagationFlags: pgflags,
Extensions: ext,
}
}
func createCgroupConfig(opts *CreateOpts) (*configs.Cgroup, error) {
var (
myCgroupPath string
spec = opts.Spec
useSystemdCgroup = opts.UseSystemdCgroup
name = opts.CgroupName
)
c := &configs.Cgroup{
Resources: &configs.Resources{},
}
if spec.Linux != nil && spec.Linux.CgroupsPath != "" {
myCgroupPath = libcontainerUtils.CleanPath(spec.Linux.CgroupsPath)
if useSystemdCgroup {
myCgroupPath = spec.Linux.CgroupsPath
}
}
if useSystemdCgroup {
if myCgroupPath == "" {
c.Parent = "system.slice"
c.ScopePrefix = "runc"
c.Name = name
} else {
// Parse the path from expected "slice:prefix:name"
// for e.g. "system.slice:docker:1234"
parts := strings.Split(myCgroupPath, ":")
if len(parts) != 3 {
return nil, fmt.Errorf("expected cgroupsPath to be of format \"slice:prefix:name\" for systemd cgroups")
}
c.Parent = parts[0]
c.ScopePrefix = parts[1]
c.Name = parts[2]
}
} else {
if myCgroupPath == "" {
c.Name = name
}
c.Path = myCgroupPath
}
// In rootless containers, any attempt to make cgroup changes will fail.
// libcontainer will validate this and we shouldn't add any cgroup options
// the user didn't specify.
if !opts.Rootless {
c.Resources.AllowedDevices = allowedDevices
}
if spec.Linux != nil {
r := spec.Linux.Resources
if r == nil {
return c, nil
}
for i, d := range spec.Linux.Resources.Devices {
var (
t = "a"
major = int64(-1)
minor = int64(-1)
)
if d.Type != "" {
t = d.Type
}
if d.Major != nil {
major = *d.Major
}
if d.Minor != nil {
minor = *d.Minor
}
if d.Access == "" {
return nil, fmt.Errorf("device access at %d field cannot be empty", i)
}
dt, err := stringToCgroupDeviceRune(t)
if err != nil {
return nil, err
}
dd := &configs.Device{
Type: dt,
Major: major,
Minor: minor,
Permissions: d.Access,
Allow: d.Allow,
}
c.Resources.Devices = append(c.Resources.Devices, dd)
}
if r.Memory != nil {
if r.Memory.Limit != nil {
c.Resources.Memory = *r.Memory.Limit
}
if r.Memory.Reservation != nil {
c.Resources.MemoryReservation = *r.Memory.Reservation
}
if r.Memory.Swap != nil {
c.Resources.MemorySwap = *r.Memory.Swap
}
if r.Memory.Kernel != nil {
c.Resources.KernelMemory = *r.Memory.Kernel
}
if r.Memory.KernelTCP != nil {
c.Resources.KernelMemoryTCP = *r.Memory.KernelTCP
}
if r.Memory.Swappiness != nil {
c.Resources.MemorySwappiness = r.Memory.Swappiness
}
if r.Memory.DisableOOMKiller != nil {
c.Resources.OomKillDisable = *r.Memory.DisableOOMKiller
}
}
if r.CPU != nil {
if r.CPU.Shares != nil {
c.Resources.CpuShares = *r.CPU.Shares
}
if r.CPU.Quota != nil {
c.Resources.CpuQuota = *r.CPU.Quota
}
if r.CPU.Period != nil {
c.Resources.CpuPeriod = *r.CPU.Period
}
if r.CPU.RealtimeRuntime != nil {
c.Resources.CpuRtRuntime = *r.CPU.RealtimeRuntime
}
if r.CPU.RealtimePeriod != nil {
c.Resources.CpuRtPeriod = *r.CPU.RealtimePeriod
}
if r.CPU.Cpus != "" {
c.Resources.CpusetCpus = r.CPU.Cpus
}
if r.CPU.Mems != "" {
c.Resources.CpusetMems = r.CPU.Mems
}
}
if r.Pids != nil {
c.Resources.PidsLimit = r.Pids.Limit
}
if r.BlockIO != nil {
if r.BlockIO.Weight != nil {
c.Resources.BlkioWeight = *r.BlockIO.Weight
}
if r.BlockIO.LeafWeight != nil {
c.Resources.BlkioLeafWeight = *r.BlockIO.LeafWeight
}
if r.BlockIO.WeightDevice != nil {
for _, wd := range r.BlockIO.WeightDevice {
var weight, leafWeight uint16
if wd.Weight != nil {
weight = *wd.Weight
}
if wd.LeafWeight != nil {
leafWeight = *wd.LeafWeight
}
weightDevice := configs.NewWeightDevice(wd.Major, wd.Minor, weight, leafWeight)
c.Resources.BlkioWeightDevice = append(c.Resources.BlkioWeightDevice, weightDevice)
}
}
if r.BlockIO.ThrottleReadBpsDevice != nil {
for _, td := range r.BlockIO.ThrottleReadBpsDevice {
rate := td.Rate
throttleDevice := configs.NewThrottleDevice(td.Major, td.Minor, rate)
c.Resources.BlkioThrottleReadBpsDevice = append(c.Resources.BlkioThrottleReadBpsDevice, throttleDevice)
}
}
if r.BlockIO.ThrottleWriteBpsDevice != nil {
for _, td := range r.BlockIO.ThrottleWriteBpsDevice {
rate := td.Rate
throttleDevice := configs.NewThrottleDevice(td.Major, td.Minor, rate)
c.Resources.BlkioThrottleWriteBpsDevice = append(c.Resources.BlkioThrottleWriteBpsDevice, throttleDevice)
}
}
if r.BlockIO.ThrottleReadIOPSDevice != nil {
for _, td := range r.BlockIO.ThrottleReadIOPSDevice {
rate := td.Rate
throttleDevice := configs.NewThrottleDevice(td.Major, td.Minor, rate)
c.Resources.BlkioThrottleReadIOPSDevice = append(c.Resources.BlkioThrottleReadIOPSDevice, throttleDevice)
}
}
if r.BlockIO.ThrottleWriteIOPSDevice != nil {
for _, td := range r.BlockIO.ThrottleWriteIOPSDevice {
rate := td.Rate
throttleDevice := configs.NewThrottleDevice(td.Major, td.Minor, rate)
c.Resources.BlkioThrottleWriteIOPSDevice = append(c.Resources.BlkioThrottleWriteIOPSDevice, throttleDevice)
}
}
}
for _, l := range r.HugepageLimits {
c.Resources.HugetlbLimit = append(c.Resources.HugetlbLimit, &configs.HugepageLimit{
Pagesize: l.Pagesize,
Limit: l.Limit,
})
}
if r.Network != nil {
if r.Network.ClassID != nil {
c.Resources.NetClsClassid = *r.Network.ClassID
}
for _, m := range r.Network.Priorities {
c.Resources.NetPrioIfpriomap = append(c.Resources.NetPrioIfpriomap, &configs.IfPrioMap{
Interface: m.Name,
Priority: int64(m.Priority),
})
}
}
}
if !opts.Rootless {
// append the default allowed devices to the end of the list
c.Resources.Devices = append(c.Resources.Devices, allowedDevices...)
}
return c, nil
}
func stringToCgroupDeviceRune(s string) (rune, error) {
switch s {
case "a":
return 'a', nil
case "b":
return 'b', nil
case "c":
return 'c', nil
default:
return 0, fmt.Errorf("invalid cgroup device type %q", s)
}
}
func stringToDeviceRune(s string) (rune, error) {
switch s {
case "p":
return 'p', nil
case "u":
return 'u', nil
case "b":
return 'b', nil
case "c":
return 'c', nil
default:
return 0, fmt.Errorf("invalid device type %q", s)
}
}
func createDevices(spec *specs.Spec, config *configs.Config) error {
// add whitelisted devices
config.Devices = []*configs.Device{
{
Type: 'c',
Path: "/dev/null",
Major: 1,
Minor: 3,
FileMode: 0666,
Uid: 0,
Gid: 0,
},
{
Type: 'c',
Path: "/dev/random",
Major: 1,
Minor: 8,
FileMode: 0666,
Uid: 0,
Gid: 0,
},
{
Type: 'c',
Path: "/dev/full",
Major: 1,
Minor: 7,
FileMode: 0666,
Uid: 0,
Gid: 0,
},
{
Type: 'c',
Path: "/dev/tty",
Major: 5,
Minor: 0,
FileMode: 0666,
Uid: 0,
Gid: 0,
},
{
Type: 'c',
Path: "/dev/zero",
Major: 1,
Minor: 5,
FileMode: 0666,
Uid: 0,
Gid: 0,
},
{
Type: 'c',
Path: "/dev/urandom",
Major: 1,
Minor: 9,
FileMode: 0666,
Uid: 0,
Gid: 0,
},
}
// merge in additional devices from the spec
if spec.Linux != nil {
for _, d := range spec.Linux.Devices {
var uid, gid uint32
var filemode os.FileMode = 0666
if d.UID != nil {
uid = *d.UID
}
if d.GID != nil {
gid = *d.GID
}
dt, err := stringToDeviceRune(d.Type)
if err != nil {
return err
}
if d.FileMode != nil {
filemode = *d.FileMode
}
device := &configs.Device{
Type: dt,
Path: d.Path,
Major: d.Major,
Minor: d.Minor,
FileMode: filemode,
Uid: uid,
Gid: gid,
}
config.Devices = append(config.Devices, device)
}
}
return nil
}
func setupUserNamespace(spec *specs.Spec, config *configs.Config) error {
create := func(m specs.LinuxIDMapping) configs.IDMap {
return configs.IDMap{
HostID: int(m.HostID),
ContainerID: int(m.ContainerID),
Size: int(m.Size),
}
}
if spec.Linux != nil {
if len(spec.Linux.UIDMappings) == 0 {
return nil
}
for _, m := range spec.Linux.UIDMappings {
config.UidMappings = append(config.UidMappings, create(m))
}
for _, m := range spec.Linux.GIDMappings {
config.GidMappings = append(config.GidMappings, create(m))
}
}
rootUID, err := config.HostRootUID()
if err != nil {
return err
}
rootGID, err := config.HostRootGID()
if err != nil {
return err
}
for _, node := range config.Devices {
node.Uid = uint32(rootUID)
node.Gid = uint32(rootGID)
}
return nil
}
// parseMountOptions parses the string and returns the flags, propagation
// flags and any mount data that it contains.
func parseMountOptions(options []string) (int, []int, string, int) {
var (
flag int
pgflag []int
data []string
extFlags int
)
flags := map[string]struct {
clear bool
flag int
}{
"acl": {false, unix.MS_POSIXACL},
"async": {true, unix.MS_SYNCHRONOUS},
"atime": {true, unix.MS_NOATIME},
"bind": {false, unix.MS_BIND},
"defaults": {false, 0},
"dev": {true, unix.MS_NODEV},
"diratime": {true, unix.MS_NODIRATIME},
"dirsync": {false, unix.MS_DIRSYNC},
"exec": {true, unix.MS_NOEXEC},
"iversion": {false, unix.MS_I_VERSION},
"lazytime": {false, unix.MS_LAZYTIME},
"loud": {true, unix.MS_SILENT},
"mand": {false, unix.MS_MANDLOCK},
"noacl": {true, unix.MS_POSIXACL},
"noatime": {false, unix.MS_NOATIME},
"nodev": {false, unix.MS_NODEV},
"nodiratime": {false, unix.MS_NODIRATIME},
"noexec": {false, unix.MS_NOEXEC},
"noiversion": {true, unix.MS_I_VERSION},
"nolazytime": {true, unix.MS_LAZYTIME},
"nomand": {true, unix.MS_MANDLOCK},
"norelatime": {true, unix.MS_RELATIME},
"nostrictatime": {true, unix.MS_STRICTATIME},
"nosuid": {false, unix.MS_NOSUID},
"rbind": {false, unix.MS_BIND | unix.MS_REC},
"relatime": {false, unix.MS_RELATIME},
"remount": {false, unix.MS_REMOUNT},
"ro": {false, unix.MS_RDONLY},
"rw": {true, unix.MS_RDONLY},
"silent": {false, unix.MS_SILENT},
"strictatime": {false, unix.MS_STRICTATIME},
"suid": {true, unix.MS_NOSUID},
"sync": {false, unix.MS_SYNCHRONOUS},
}
propagationFlags := map[string]int{
"private": unix.MS_PRIVATE,
"shared": unix.MS_SHARED,
"slave": unix.MS_SLAVE,
"unbindable": unix.MS_UNBINDABLE,
"rprivate": unix.MS_PRIVATE | unix.MS_REC,
"rshared": unix.MS_SHARED | unix.MS_REC,
"rslave": unix.MS_SLAVE | unix.MS_REC,
"runbindable": unix.MS_UNBINDABLE | unix.MS_REC,
}
extensionFlags := map[string]struct {
clear bool
flag int
}{
"tmpcopyup": {false, configs.EXT_COPYUP},
}
for _, o := range options {
// If the option does not exist in the flags table or the flag
// is not supported on the platform,
// then it is a data value for a specific fs type
if f, exists := flags[o]; exists && f.flag != 0 {
if f.clear {
flag &= ^f.flag
} else {
flag |= f.flag
}
} else if f, exists := propagationFlags[o]; exists && f != 0 {
pgflag = append(pgflag, f)
} else if f, exists := extensionFlags[o]; exists && f.flag != 0 {
if f.clear {
extFlags &= ^f.flag
} else {
extFlags |= f.flag
}
} else {
data = append(data, o)
}
}
return flag, pgflag, strings.Join(data, ","), extFlags
}
func setupSeccomp(config *specs.LinuxSeccomp) (*configs.Seccomp, error) {
if config == nil {
return nil, nil
}
// No default action specified, no syscalls listed, assume seccomp disabled
if config.DefaultAction == "" && len(config.Syscalls) == 0 {
return nil, nil
}
newConfig := new(configs.Seccomp)
newConfig.Syscalls = []*configs.Syscall{}
if len(config.Architectures) > 0 {
newConfig.Architectures = []string{}
for _, arch := range config.Architectures {
newArch, err := seccomp.ConvertStringToArch(string(arch))
if err != nil {
return nil, err
}
newConfig.Architectures = append(newConfig.Architectures, newArch)
}
}
// Convert default action from string representation
newDefaultAction, err := seccomp.ConvertStringToAction(string(config.DefaultAction))
if err != nil {
return nil, err
}
newConfig.DefaultAction = newDefaultAction
// Loop through all syscall blocks and convert them to libcontainer format
for _, call := range config.Syscalls {
newAction, err := seccomp.ConvertStringToAction(string(call.Action))
if err != nil {
return nil, err
}
for _, name := range call.Names {
newCall := configs.Syscall{
Name: name,
Action: newAction,
Args: []*configs.Arg{},
}
// Loop through all the arguments of the syscall and convert them
for _, arg := range call.Args {
newOp, err := seccomp.ConvertStringToOperator(string(arg.Op))
if err != nil {
return nil, err
}
newArg := configs.Arg{
Index: arg.Index,
Value: arg.Value,
ValueTwo: arg.ValueTwo,
Op: newOp,
}
newCall.Args = append(newCall.Args, &newArg)
}
newConfig.Syscalls = append(newConfig.Syscalls, &newCall)
}
}
return newConfig, nil
}
func createHooks(rspec *specs.Spec, config *configs.Config) {
config.Hooks = &configs.Hooks{}
if rspec.Hooks != nil {
for _, h := range rspec.Hooks.Prestart {
cmd := createCommandHook(h)
config.Hooks.Prestart = append(config.Hooks.Prestart, configs.NewCommandHook(cmd))
}
for _, h := range rspec.Hooks.Poststart {
cmd := createCommandHook(h)
config.Hooks.Poststart = append(config.Hooks.Poststart, configs.NewCommandHook(cmd))
}
for _, h := range rspec.Hooks.Poststop {
cmd := createCommandHook(h)
config.Hooks.Poststop = append(config.Hooks.Poststop, configs.NewCommandHook(cmd))
}
}
}
func createCommandHook(h specs.Hook) configs.Command {
cmd := configs.Command{
Path: h.Path,
Args: h.Args,
Env: h.Env,
}
if h.Timeout != nil {
d := time.Duration(*h.Timeout) * time.Second
cmd.Timeout = &d
}
return cmd
}