// Init is the init process that first runs inside a new namespace to setup mounts, users, networking,
// and other options required for the new container.
func (ns *linuxNs) Init(container *libcontainer.Container, uncleanRootfs, consolePath string, syncPipe *SyncPipe, args []string) error {
rootfs, err := utils.ResolveRootfs(uncleanRootfs)
if err != nil {
return err
}
// We always read this as it is a way to sync with the parent as well
ns.logger.Printf("reading from sync pipe fd %d\n", syncPipe.child.Fd())
context, err := syncPipe.ReadFromParent()
if err != nil {
syncPipe.Close()
return err
}
ns.logger.Println("received context from parent")
syncPipe.Close()
if consolePath != "" {
ns.logger.Printf("setting up %s as console\n", consolePath)
if err := console.OpenAndDup(consolePath); err != nil {
return err
}
}
if _, err := system.Setsid(); err != nil {
return fmt.Errorf("setsid %s", err)
}
if consolePath != "" {
if err := system.Setctty(); err != nil {
return fmt.Errorf("setctty %s", err)
}
}
if err := setupNetwork(container, context); err != nil {
return fmt.Errorf("setup networking %s", err)
}
label.Init()
ns.logger.Println("setup mount namespace")
if err := mount.InitializeMountNamespace(rootfs, consolePath, container); err != nil {
return fmt.Errorf("setup mount namespace %s", err)
}
if err := system.Sethostname(container.Hostname); err != nil {
return fmt.Errorf("sethostname %s", err)
}
if err := finalizeNamespace(container); err != nil {
return fmt.Errorf("finalize namespace %s", err)
}
if profile := container.Context["apparmor_profile"]; profile != "" {
ns.logger.Printf("setting apparmor profile %s\n", profile)
if err := apparmor.ApplyProfile(os.Getpid(), profile); err != nil {
return err
}
}
runtime.LockOSThread()
if err := label.SetProcessLabel(container.Context["process_label"]); err != nil {
return fmt.Errorf("SetProcessLabel label %s", err)
}
ns.logger.Printf("execing %s\n", args[0])
return system.Execv(args[0], args[0:], container.Env)
}
// NsEnter is run after entering the namespace.
func NsEnter(container *libcontainer.Container, processLabel string, nspid int, args []string) error {
// clear the current processes env and replace it with the environment
// defined on the container
if err := LoadContainerEnvironment(container); err != nil {
return err
}
if err := FinalizeNamespace(container); err != nil {
return err
}
if err := label.SetProcessLabel(processLabel); err != nil {
return err
}
if err := system.Execv(args[0], args[0:], container.Env); err != nil {
return err
}
panic("unreachable")
}
// Init is the init process that first runs inside a new namespace to setup mounts, users, networking,
// and other options required for the new container.
func (ns *linuxNs) Init(container *libcontainer.Container, uncleanRootfs, console string, syncPipe *SyncPipe, args []string) error {
rootfs, err := utils.ResolveRootfs(uncleanRootfs)
if err != nil {
return err
}
// We always read this as it is a way to sync with the parent as well
ns.logger.Printf("reading from sync pipe fd %d\n", syncPipe.child.Fd())
context, err := syncPipe.ReadFromParent()
if err != nil {
syncPipe.Close()
return err
}
ns.logger.Println("received context from parent")
syncPipe.Close()
if console != "" {
ns.logger.Printf("setting up %s as console\n", console)
slave, err := system.OpenTerminal(console, syscall.O_RDWR)
if err != nil {
return fmt.Errorf("open terminal %s", err)
}
if err := dupSlave(slave); err != nil {
return fmt.Errorf("dup2 slave %s", err)
}
}
if _, err := system.Setsid(); err != nil {
return fmt.Errorf("setsid %s", err)
}
if console != "" {
if err := system.Setctty(); err != nil {
return fmt.Errorf("setctty %s", err)
}
}
// this is our best effort to let the process know that the parent has died and that it
// should it should act on it how it sees fit
if err := system.ParentDeathSignal(uintptr(syscall.SIGTERM)); err != nil {
return fmt.Errorf("parent death signal %s", err)
}
ns.logger.Println("setup mount namespace")
if err := setupNewMountNamespace(rootfs, container.Mounts, console, container.ReadonlyFs, container.NoPivotRoot, container.Context["mount_label"]); err != nil {
return fmt.Errorf("setup mount namespace %s", err)
}
if err := setupNetwork(container, context); err != nil {
return fmt.Errorf("setup networking %s", err)
}
if err := system.Sethostname(container.Hostname); err != nil {
return fmt.Errorf("sethostname %s", err)
}
if err := finalizeNamespace(container); err != nil {
return fmt.Errorf("finalize namespace %s", err)
}
if profile := container.Context["apparmor_profile"]; profile != "" {
ns.logger.Printf("setting apparmor profile %s\n", profile)
if err := apparmor.ApplyProfile(os.Getpid(), profile); err != nil {
return err
}
}
runtime.LockOSThread()
if err := label.SetProcessLabel(container.Context["process_label"]); err != nil {
return fmt.Errorf("SetProcessLabel label %s", err)
}
ns.logger.Printf("execing %s\n", args[0])
return system.Execv(args[0], args[0:], container.Env)
}
// Init is the init process that first runs inside a new namespace to setup mounts, users, networking,
// and other options required for the new container.
func Init(container *libcontainer.Container, uncleanRootfs, consolePath string, syncPipe *SyncPipe, args []string) error {
rootfs, err := utils.ResolveRootfs(uncleanRootfs)
if err != nil {
return err
}
// clear the current processes env and replace it with the environment
// defined on the container
if err := LoadContainerEnvironment(container); err != nil {
return err
}
// We always read this as it is a way to sync with the parent as well
context, err := syncPipe.ReadFromParent()
if err != nil {
syncPipe.Close()
return err
}
syncPipe.Close()
if consolePath != "" {
if err := console.OpenAndDup(consolePath); err != nil {
return err
}
}
if _, err := system.Setsid(); err != nil {
return fmt.Errorf("setsid %s", err)
}
if consolePath != "" {
if err := system.Setctty(); err != nil {
return fmt.Errorf("setctty %s", err)
}
}
if err := setupNetwork(container, context); err != nil {
return fmt.Errorf("setup networking %s", err)
}
label.Init()
if err := mount.InitializeMountNamespace(rootfs, consolePath, container); err != nil {
return fmt.Errorf("setup mount namespace %s", err)
}
if container.Hostname != "" {
if err := system.Sethostname(container.Hostname); err != nil {
return fmt.Errorf("sethostname %s", err)
}
}
runtime.LockOSThread()
if err := apparmor.ApplyProfile(container.Context["apparmor_profile"]); err != nil {
return fmt.Errorf("set apparmor profile %s: %s", container.Context["apparmor_profile"], err)
}
if err := label.SetProcessLabel(container.Context["process_label"]); err != nil {
return fmt.Errorf("set process label %s", err)
}
if container.Context["restrictions"] != "" {
if err := restrict.Restrict("proc", "sys"); err != nil {
return err
}
}
if err := FinalizeNamespace(container); err != nil {
return fmt.Errorf("finalize namespace %s", err)
}
return system.Execv(args[0], args[0:], container.Env)
}
// ExecIn uses an existing pid and joins the pid's namespaces with the new command.
func ExecIn(container *libcontainer.Container, nspid int, args []string) (int, error) {
// clear the current processes env and replace it with the environment
// defined on the container
if err := LoadContainerEnvironment(container); err != nil {
return -1, err
}
for key, enabled := range container.Namespaces {
// skip the PID namespace on unshare because it it not supported
if enabled && key != "NEWPID" {
if ns := libcontainer.GetNamespace(key); ns != nil {
if err := system.Unshare(ns.Value); err != nil {
return -1, err
}
}
}
}
fds, err := getNsFds(nspid, container)
closeFds := func() {
for _, f := range fds {
system.Closefd(f)
}
}
if err != nil {
closeFds()
return -1, err
}
processLabel, err := label.GetPidCon(nspid)
if err != nil {
closeFds()
return -1, err
}
// foreach namespace fd, use setns to join an existing container's namespaces
for _, fd := range fds {
if fd > 0 {
if err := system.Setns(fd, 0); err != nil {
closeFds()
return -1, fmt.Errorf("setns %s", err)
}
}
system.Closefd(fd)
}
// if the container has a new pid and mount namespace we need to
// remount proc and sys to pick up the changes
if container.Namespaces["NEWNS"] && container.Namespaces["NEWPID"] {
pid, err := system.Fork()
if err != nil {
return -1, err
}
if pid == 0 {
// TODO: make all raw syscalls to be fork safe
if err := system.Unshare(syscall.CLONE_NEWNS); err != nil {
return -1, err
}
if err := mount.RemountProc(); err != nil {
return -1, fmt.Errorf("remount proc %s", err)
}
if err := mount.RemountSys(); err != nil {
return -1, fmt.Errorf("remount sys %s", err)
}
goto dropAndExec
}
proc, err := os.FindProcess(pid)
if err != nil {
return -1, err
}
state, err := proc.Wait()
if err != nil {
return -1, err
}
os.Exit(state.Sys().(syscall.WaitStatus).ExitStatus())
}
dropAndExec:
if err := FinalizeNamespace(container); err != nil {
return -1, err
}
err = label.SetProcessLabel(processLabel)
if err != nil {
return -1, err
}
if err := system.Execv(args[0], args[0:], container.Env); err != nil {
return -1, err
}
panic("unreachable")
}
// ExecIn uses an existing pid and joins the pid's namespaces with the new command.
func (ns *linuxNs) ExecIn(container *libcontainer.Container, nspid int, args []string) (int, error) {
for _, nsv := range container.Namespaces {
// skip the PID namespace on unshare because it it not supported
if nsv.Key != "NEWPID" {
if err := system.Unshare(nsv.Value); err != nil {
return -1, err
}
}
}
fds, err := ns.getNsFds(nspid, container)
closeFds := func() {
for _, f := range fds {
system.Closefd(f)
}
}
if err != nil {
closeFds()
return -1, err
}
processLabel, err := label.GetPidCon(nspid)
if err != nil {
closeFds()
return -1, err
}
// foreach namespace fd, use setns to join an existing container's namespaces
for _, fd := range fds {
if fd > 0 {
ns.logger.Printf("setns on %d\n", fd)
if err := system.Setns(fd, 0); err != nil {
closeFds()
return -1, fmt.Errorf("setns %s", err)
}
}
system.Closefd(fd)
}
// if the container has a new pid and mount namespace we need to
// remount proc and sys to pick up the changes
if container.Namespaces.Contains("NEWNS") && container.Namespaces.Contains("NEWPID") {
ns.logger.Println("forking to remount /proc and /sys")
pid, err := system.Fork()
if err != nil {
return -1, err
}
if pid == 0 {
// TODO: make all raw syscalls to be fork safe
if err := system.Unshare(syscall.CLONE_NEWNS); err != nil {
return -1, err
}
if err := mount.RemountProc(); err != nil {
return -1, fmt.Errorf("remount proc %s", err)
}
if err := mount.RemountSys(); err != nil {
return -1, fmt.Errorf("remount sys %s", err)
}
goto dropAndExec
}
proc, err := os.FindProcess(pid)
if err != nil {
return -1, err
}
state, err := proc.Wait()
if err != nil {
return -1, err
}
os.Exit(state.Sys().(syscall.WaitStatus).ExitStatus())
}
dropAndExec:
if err := finalizeNamespace(container); err != nil {
return -1, err
}
err = label.SetProcessLabel(processLabel)
if err != nil {
return -1, err
}
if err := system.Execv(args[0], args[0:], container.Env); err != nil {
return -1, err
}
panic("unreachable")
}