runc/nsinit/config.go

303 lines
9.0 KiB
Go

package main
import (
"bytes"
"encoding/json"
"io"
"math"
"os"
"path/filepath"
"strings"
"syscall"
"github.com/Sirupsen/logrus"
"github.com/codegangsta/cli"
"github.com/docker/libcontainer/configs"
"github.com/docker/libcontainer/utils"
)
const defaultMountFlags = syscall.MS_NOEXEC | syscall.MS_NOSUID | syscall.MS_NODEV
var createFlags = []cli.Flag{
cli.IntFlag{Name: "parent-death-signal", Usage: "set the signal that will be delivered to the process in case the parent dies"},
cli.BoolFlag{Name: "read-only", Usage: "set the container's rootfs as read-only"},
cli.StringSliceFlag{Name: "bind", Value: &cli.StringSlice{}, Usage: "add bind mounts to the container"},
cli.StringSliceFlag{Name: "tmpfs", Value: &cli.StringSlice{}, Usage: "add tmpfs mounts to the container"},
cli.IntFlag{Name: "cpushares", Usage: "set the cpushares for the container"},
cli.IntFlag{Name: "memory-limit", Usage: "set the memory limit for the container"},
cli.IntFlag{Name: "memory-swap", Usage: "set the memory swap limit for the container"},
cli.StringFlag{Name: "cpuset-cpus", Usage: "set the cpuset cpus"},
cli.StringFlag{Name: "cpuset-mems", Usage: "set the cpuset mems"},
cli.StringFlag{Name: "apparmor-profile", Usage: "set the apparmor profile"},
cli.StringFlag{Name: "process-label", Usage: "set the process label"},
cli.StringFlag{Name: "mount-label", Usage: "set the mount label"},
cli.StringFlag{Name: "rootfs", Usage: "set the rootfs"},
cli.IntFlag{Name: "userns-root-uid", Usage: "set the user namespace root uid"},
cli.StringFlag{Name: "hostname", Value: "nsinit", Usage: "hostname value for the container"},
cli.StringFlag{Name: "net", Value: "", Usage: "network namespace"},
cli.StringFlag{Name: "ipc", Value: "", Usage: "ipc namespace"},
cli.StringFlag{Name: "pid", Value: "", Usage: "pid namespace"},
cli.StringFlag{Name: "uts", Value: "", Usage: "uts namespace"},
cli.StringFlag{Name: "mnt", Value: "", Usage: "mount namespace"},
cli.StringFlag{Name: "veth-bridge", Usage: "veth bridge"},
cli.StringFlag{Name: "veth-address", Usage: "veth ip address"},
cli.StringFlag{Name: "veth-gateway", Usage: "veth gateway address"},
cli.IntFlag{Name: "veth-mtu", Usage: "veth mtu"},
cli.BoolFlag{Name: "cgroup", Usage: "mount the cgroup data for the container"},
cli.StringSliceFlag{Name: "sysctl", Value: &cli.StringSlice{}, Usage: "set system properties in the container"},
}
var configCommand = cli.Command{
Name: "config",
Usage: "generate a standard configuration file for a container",
Flags: append([]cli.Flag{
cli.StringFlag{Name: "file,f", Value: "stdout", Usage: "write the configuration to the specified file"},
}, createFlags...),
Action: func(context *cli.Context) {
template := getTemplate()
modify(template, context)
data, err := json.MarshalIndent(template, "", "\t")
if err != nil {
fatal(err)
}
var f *os.File
filePath := context.String("file")
switch filePath {
case "stdout", "":
f = os.Stdout
default:
if f, err = os.Create(filePath); err != nil {
fatal(err)
}
defer f.Close()
}
if _, err := io.Copy(f, bytes.NewBuffer(data)); err != nil {
fatal(err)
}
},
}
func modify(config *configs.Config, context *cli.Context) {
config.ParentDeathSignal = context.Int("parent-death-signal")
config.Readonlyfs = context.Bool("read-only")
config.Cgroups.CpusetCpus = context.String("cpuset-cpus")
config.Cgroups.CpusetMems = context.String("cpuset-mems")
config.Cgroups.CpuShares = int64(context.Int("cpushares"))
config.Cgroups.Memory = int64(context.Int("memory-limit"))
config.Cgroups.MemorySwap = int64(context.Int("memory-swap"))
config.AppArmorProfile = context.String("apparmor-profile")
config.ProcessLabel = context.String("process-label")
config.MountLabel = context.String("mount-label")
rootfs := context.String("rootfs")
if rootfs != "" {
config.Rootfs = rootfs
}
userns_uid := context.Int("userns-root-uid")
if userns_uid != 0 {
config.Namespaces.Add(configs.NEWUSER, "")
config.UidMappings = []configs.IDMap{
{ContainerID: 0, HostID: userns_uid, Size: 1},
{ContainerID: 1, HostID: 1, Size: userns_uid - 1},
{ContainerID: userns_uid + 1, HostID: userns_uid + 1, Size: math.MaxInt32 - userns_uid},
}
config.GidMappings = []configs.IDMap{
{ContainerID: 0, HostID: userns_uid, Size: 1},
{ContainerID: 1, HostID: 1, Size: userns_uid - 1},
{ContainerID: userns_uid + 1, HostID: userns_uid + 1, Size: math.MaxInt32 - userns_uid},
}
for _, node := range config.Devices {
node.Uid = uint32(userns_uid)
node.Gid = uint32(userns_uid)
}
}
config.SystemProperties = make(map[string]string)
for _, sysProp := range context.StringSlice("sysctl") {
parts := strings.SplitN(sysProp, "=", 2)
if len(parts) != 2 {
logrus.Fatalf("invalid system property %s", sysProp)
}
config.SystemProperties[parts[0]] = parts[1]
}
for _, rawBind := range context.StringSlice("bind") {
mount := &configs.Mount{
Device: "bind",
Flags: syscall.MS_BIND | syscall.MS_REC,
}
parts := strings.SplitN(rawBind, ":", 3)
switch len(parts) {
default:
logrus.Fatalf("invalid bind mount %s", rawBind)
case 2:
mount.Source, mount.Destination = parts[0], parts[1]
case 3:
mount.Source, mount.Destination = parts[0], parts[1]
switch parts[2] {
case "ro":
mount.Flags |= syscall.MS_RDONLY
case "rw":
default:
logrus.Fatalf("invalid bind mount mode %s", parts[2])
}
}
config.Mounts = append(config.Mounts, mount)
}
for _, tmpfs := range context.StringSlice("tmpfs") {
config.Mounts = append(config.Mounts, &configs.Mount{
Device: "tmpfs",
Destination: tmpfs,
Flags: syscall.MS_NOEXEC | syscall.MS_NOSUID | syscall.MS_NODEV,
})
}
for flag, value := range map[string]configs.NamespaceType{
"net": configs.NEWNET,
"mnt": configs.NEWNS,
"pid": configs.NEWPID,
"ipc": configs.NEWIPC,
"uts": configs.NEWUTS,
} {
switch v := context.String(flag); v {
case "host":
config.Namespaces.Remove(value)
case "", "private":
if !config.Namespaces.Contains(value) {
config.Namespaces.Add(value, "")
}
if flag == "net" {
config.Networks = []*configs.Network{
{
Type: "loopback",
Address: "127.0.0.1/0",
Gateway: "localhost",
},
}
}
if flag == "uts" {
config.Hostname = context.String("hostname")
}
default:
config.Namespaces.Remove(value)
config.Namespaces.Add(value, v)
}
}
if bridge := context.String("veth-bridge"); bridge != "" {
hostName, err := utils.GenerateRandomName("veth", 7)
if err != nil {
logrus.Fatal(err)
}
network := &configs.Network{
Type: "veth",
Name: "eth0",
Bridge: bridge,
Address: context.String("veth-address"),
Gateway: context.String("veth-gateway"),
Mtu: context.Int("veth-mtu"),
HostInterfaceName: hostName,
}
config.Networks = append(config.Networks, network)
}
if context.Bool("cgroup") {
config.Mounts = append(config.Mounts, &configs.Mount{
Destination: "/sys/fs/cgroup",
Device: "cgroup",
})
}
}
func getTemplate() *configs.Config {
cwd, err := os.Getwd()
if err != nil {
panic(err)
}
return &configs.Config{
Rootfs: cwd,
ParentDeathSignal: int(syscall.SIGKILL),
Capabilities: []string{
"CHOWN",
"DAC_OVERRIDE",
"FSETID",
"FOWNER",
"MKNOD",
"NET_RAW",
"SETGID",
"SETUID",
"SETFCAP",
"SETPCAP",
"NET_BIND_SERVICE",
"SYS_CHROOT",
"KILL",
"AUDIT_WRITE",
},
Namespaces: configs.Namespaces([]configs.Namespace{
{Type: configs.NEWNS},
{Type: configs.NEWUTS},
{Type: configs.NEWIPC},
{Type: configs.NEWPID},
{Type: configs.NEWNET},
}),
Cgroups: &configs.Cgroup{
Name: filepath.Base(cwd),
Parent: "nsinit",
AllowAllDevices: false,
AllowedDevices: configs.DefaultAllowedDevices,
},
Devices: configs.DefaultAutoCreatedDevices,
MaskPaths: []string{
"/proc/kcore",
},
ReadonlyPaths: []string{
"/proc/sys", "/proc/sysrq-trigger", "/proc/irq", "/proc/bus",
},
Mounts: []*configs.Mount{
{
Source: "proc",
Destination: "/proc",
Device: "proc",
Flags: defaultMountFlags,
},
{
Source: "tmpfs",
Destination: "/dev",
Device: "tmpfs",
Flags: syscall.MS_NOSUID | syscall.MS_STRICTATIME,
Data: "mode=755",
},
{
Source: "devpts",
Destination: "/dev/pts",
Device: "devpts",
Flags: syscall.MS_NOSUID | syscall.MS_NOEXEC,
Data: "newinstance,ptmxmode=0666,mode=0620,gid=5",
},
{
Device: "tmpfs",
Source: "shm",
Destination: "/dev/shm",
Data: "mode=1777,size=65536k",
Flags: defaultMountFlags,
},
{
Source: "mqueue",
Destination: "/dev/mqueue",
Device: "mqueue",
Flags: defaultMountFlags,
},
{
Source: "sysfs",
Destination: "/sys",
Device: "sysfs",
Flags: defaultMountFlags | syscall.MS_RDONLY,
},
},
Rlimits: []configs.Rlimit{
{
Type: syscall.RLIMIT_NOFILE,
Hard: 1024,
Soft: 1024,
},
},
}
}