// setup standard pipes so that the TTY of the calling runc process
// is not inherited by the container.
func createStdioPipes(p *libcontainer.Process, rootuid int) (*tty, error) {
var (
t = &tty{}
fds []int
)
r, w, err := os.Pipe()
if err != nil {
return nil, err
}
fds = append(fds, int(r.Fd()), int(w.Fd()))
go io.Copy(w, os.Stdin)
t.closers = append(t.closers, w)
p.Stdin = r
if r, w, err = os.Pipe(); err != nil {
return nil, err
}
fds = append(fds, int(r.Fd()), int(w.Fd()))
go io.Copy(os.Stdout, r)
p.Stdout = w
t.closers = append(t.closers, r)
if r, w, err = os.Pipe(); err != nil {
return nil, err
}
fds = append(fds, int(r.Fd()), int(w.Fd()))
go io.Copy(os.Stderr, r)
p.Stderr = w
t.closers = append(t.closers, r)
// change the ownership of the pipe fds incase we are in a user namespace.
for _, fd := range fds {
if err := syscall.Fchown(fd, rootuid, rootuid); err != nil {
return nil, err
}
}
return t, nil
}
func dupStdio(process *libcontainer.Process, rootuid int) error {
process.Stdin = os.Stdin
process.Stdout = os.Stdout
process.Stderr = os.Stderr
for _, fd := range []uintptr{
os.Stdin.Fd(),
os.Stdout.Fd(),
os.Stderr.Fd(),
} {
if err := syscall.Fchown(int(fd), rootuid, rootuid); err != nil {
return err
}
}
return nil
}
// setupIO modifies the given process config according to the options.
func setupIO(process *libcontainer.Process, rootuid, rootgid int, createTTY, detach bool) (*tty, error) {
// This is entirely handled by recvtty.
if createTTY {
process.Stdin = nil
process.Stdout = nil
process.Stderr = nil
return &tty{}, nil
}
// When we detach, we just dup over stdio and call it a day. There's no
// requirement that we set up anything nice for our caller or the
// container.
if detach {
if err := dupStdio(process, rootuid, rootgid); err != nil {
return nil, err
}
return &tty{}, nil
}
// XXX: This doesn't sit right with me. It's ugly.
return createStdioPipes(process, rootuid, rootgid)
}
func createTty(p *libcontainer.Process, rootuid int) (*tty, error) {
console, err := p.NewConsole(rootuid)
if err != nil {
return nil, err
}
go io.Copy(console, os.Stdin)
go io.Copy(os.Stdout, console)
state, err := term.SetRawTerminal(os.Stdin.Fd())
if err != nil {
return nil, err
}
t := &tty{
console: console,
state: state,
closers: []io.Closer{
console,
},
}
p.Stderr = nil
p.Stdout = nil
p.Stdin = nil
return t, nil
}
func setupPipes(container *configs.Config, processConfig *execdriver.ProcessConfig, p *libcontainer.Process, pipes *execdriver.Pipes) error {
var term execdriver.Terminal
var err error
if processConfig.Tty {
rootuid, err := container.HostUID()
if err != nil {
return err
}
cons, err := p.NewConsole(rootuid)
if err != nil {
return err
}
term, err = NewTtyConsole(cons, pipes)
} else {
p.Stdout = pipes.Stdout
p.Stderr = pipes.Stderr
r, w, err := os.Pipe()
if err != nil {
return err
}
if pipes.Stdin != nil {
go func() {
io.Copy(w, pipes.Stdin)
w.Close()
}()
p.Stdin = r
}
term = &execdriver.StdConsole{}
}
if err != nil {
return err
}
processConfig.Terminal = term
return nil
}
// setup standard pipes so that the TTY of the calling runc process
// is not inherited by the container.
func createStdioPipes(p *libcontainer.Process) (*tty, error) {
t := &tty{}
r, w, err := os.Pipe()
if err != nil {
return nil, err
}
go io.Copy(w, os.Stdin)
t.closers = append(t.closers, w)
p.Stdin = r
if r, w, err = os.Pipe(); err != nil {
return nil, err
}
go io.Copy(os.Stdout, r)
p.Stdout = w
t.closers = append(t.closers, r)
if r, w, err = os.Pipe(); err != nil {
return nil, err
}
go io.Copy(os.Stderr, r)
p.Stderr = w
t.closers = append(t.closers, r)
return t, nil
}
func setupPipes(container *configs.Config, processConfig *execdriver.ProcessConfig, p *libcontainer.Process, pipes *execdriver.Pipes) error {
rootuid, err := container.HostUID()
if err != nil {
return err
}
if processConfig.Tty {
cons, err := p.NewConsole(rootuid)
if err != nil {
return err
}
term, err := NewTtyConsole(cons, pipes)
if err != nil {
return err
}
processConfig.Terminal = term
return nil
}
// not a tty--set up stdio pipes
term := &execdriver.StdConsole{}
processConfig.Terminal = term
// if we are not in a user namespace, there is no reason to go through
// the hassle of setting up os-level pipes with proper (remapped) ownership
// so we will do the prior shortcut for non-userns containers
if rootuid == 0 {
p.Stdout = pipes.Stdout
p.Stderr = pipes.Stderr
r, w, err := os.Pipe()
if err != nil {
return err
}
if pipes.Stdin != nil {
go func() {
io.Copy(w, pipes.Stdin)
w.Close()
}()
p.Stdin = r
}
return nil
}
// if we have user namespaces enabled (rootuid != 0), we will set
// up os pipes for stderr, stdout, stdin so we can chown them to
// the proper ownership to allow for proper access to the underlying
// fds
var fds []int
//setup stdout
r, w, err := os.Pipe()
if err != nil {
return err
}
fds = append(fds, int(r.Fd()), int(w.Fd()))
if pipes.Stdout != nil {
go io.Copy(pipes.Stdout, r)
}
term.Closers = append(term.Closers, r)
p.Stdout = w
//setup stderr
r, w, err = os.Pipe()
if err != nil {
return err
}
fds = append(fds, int(r.Fd()), int(w.Fd()))
if pipes.Stderr != nil {
go io.Copy(pipes.Stderr, r)
}
term.Closers = append(term.Closers, r)
p.Stderr = w
//setup stdin
r, w, err = os.Pipe()
if err != nil {
return err
}
fds = append(fds, int(r.Fd()), int(w.Fd()))
if pipes.Stdin != nil {
go func() {
io.Copy(w, pipes.Stdin)
w.Close()
}()
p.Stdin = r
}
for _, fd := range fds {
if err := syscall.Fchown(fd, rootuid, rootuid); err != nil {
return fmt.Errorf("Failed to chown pipes fd: %v", err)
}
}
return nil
}
func TestEnter(t *testing.T) {
if testing.Short() {
return
}
root, err := newTestRoot()
ok(t, err)
defer os.RemoveAll(root)
rootfs, err := newRootfs()
ok(t, err)
defer remove(rootfs)
config := newTemplateConfig(rootfs)
container, err := factory.Create("test", config)
ok(t, err)
defer container.Destroy()
// Execute a first process in the container
stdinR, stdinW, err := os.Pipe()
ok(t, err)
var stdout, stdout2 bytes.Buffer
pconfig := libcontainer.Process{
Args: []string{"sh", "-c", "cat && readlink /proc/self/ns/pid"},
Env: standardEnvironment,
Stdin: stdinR,
Stdout: &stdout,
}
err = container.Start(&pconfig)
stdinR.Close()
defer stdinW.Close()
ok(t, err)
pid, err := pconfig.Pid()
ok(t, err)
// Execute another process in the container
stdinR2, stdinW2, err := os.Pipe()
ok(t, err)
pconfig2 := libcontainer.Process{
Env: standardEnvironment,
}
pconfig2.Args = []string{"sh", "-c", "cat && readlink /proc/self/ns/pid"}
pconfig2.Stdin = stdinR2
pconfig2.Stdout = &stdout2
err = container.Start(&pconfig2)
stdinR2.Close()
defer stdinW2.Close()
ok(t, err)
pid2, err := pconfig2.Pid()
ok(t, err)
processes, err := container.Processes()
ok(t, err)
n := 0
for i := range processes {
if processes[i] == pid || processes[i] == pid2 {
n++
}
}
if n != 2 {
t.Fatal("unexpected number of processes", processes, pid, pid2)
}
// Wait processes
stdinW2.Close()
waitProcess(&pconfig2, t)
stdinW.Close()
waitProcess(&pconfig, t)
// Check that both processes live in the same pidns
pidns := string(stdout.Bytes())
ok(t, err)
pidns2 := string(stdout2.Bytes())
ok(t, err)
if pidns != pidns2 {
t.Fatal("The second process isn't in the required pid namespace", pidns, pidns2)
}
}
func setupPipes(container *configs.Config, processConfig *execdriver.ProcessConfig, p *libcontainer.Process, pipes *execdriver.Pipes, wg *sync.WaitGroup) ([]io.WriteCloser, error) {
writers := []io.WriteCloser{}
rootuid, err := container.HostUID()
if err != nil {
return writers, err
}
if processConfig.Tty {
cons, err := p.NewConsole(rootuid)
if err != nil {
return writers, err
}
term, err := NewTtyConsole(cons, pipes)
if err != nil {
return writers, err
}
processConfig.Terminal = term
return writers, nil
}
// not a tty--set up stdio pipes
term := &execdriver.StdConsole{}
processConfig.Terminal = term
// if we are not in a user namespace, there is no reason to go through
// the hassle of setting up os-level pipes with proper (remapped) ownership
// so we will do the prior shortcut for non-userns containers
if rootuid == 0 {
p.Stdout = pipes.Stdout
p.Stderr = pipes.Stderr
r, w, err := os.Pipe()
if err != nil {
return writers, err
}
if pipes.Stdin != nil {
go func() {
io.Copy(w, pipes.Stdin)
w.Close()
}()
p.Stdin = r
}
return writers, nil
}
// if we have user namespaces enabled (rootuid != 0), we will set
// up os pipes for stderr, stdout, stdin so we can chown them to
// the proper ownership to allow for proper access to the underlying
// fds
var fds []uintptr
copyPipes := func(out io.Writer, in io.ReadCloser) {
defer wg.Done()
io.Copy(out, in)
in.Close()
}
//setup stdout
r, w, err := os.Pipe()
if err != nil {
w.Close()
return writers, err
}
writers = append(writers, w)
fds = append(fds, r.Fd(), w.Fd())
if pipes.Stdout != nil {
wg.Add(1)
go copyPipes(pipes.Stdout, r)
}
term.Closers = append(term.Closers, r)
p.Stdout = w
//setup stderr
r, w, err = os.Pipe()
if err != nil {
w.Close()
return writers, err
}
writers = append(writers, w)
fds = append(fds, r.Fd(), w.Fd())
if pipes.Stderr != nil {
wg.Add(1)
go copyPipes(pipes.Stderr, r)
}
term.Closers = append(term.Closers, r)
p.Stderr = w
//setup stdin
r, w, err = os.Pipe()
if err != nil {
r.Close()
return writers, err
}
fds = append(fds, r.Fd(), w.Fd())
if pipes.Stdin != nil {
go func() {
io.Copy(w, pipes.Stdin)
w.Close()
}()
p.Stdin = r
}
for _, fd := range fds {
if err := syscall.Fchown(int(fd), rootuid, rootuid); err != nil {
return writers, fmt.Errorf("Failed to chown pipes fd: %v", err)
}
}
return writers, nil
}