runc/libcontainer/setns_init_linux.go

84 lines
2.5 KiB
Go

// +build linux
package libcontainer
import (
"fmt"
"os"
"github.com/opencontainers/runc/libcontainer/apparmor"
"github.com/opencontainers/runc/libcontainer/keys"
"github.com/opencontainers/runc/libcontainer/seccomp"
"github.com/opencontainers/runc/libcontainer/system"
"github.com/opencontainers/selinux/go-selinux/label"
"github.com/pkg/errors"
"golang.org/x/sys/unix"
)
// linuxSetnsInit performs the container's initialization for running a new process
// inside an existing container.
type linuxSetnsInit struct {
pipe *os.File
consoleSocket *os.File
config *initConfig
}
func (l *linuxSetnsInit) getSessionRingName() string {
return fmt.Sprintf("_ses.%s", l.config.ContainerId)
}
func (l *linuxSetnsInit) Init() error {
if !l.config.Config.NoNewKeyring {
// Do not inherit the parent's session keyring.
if _, err := keys.JoinSessionKeyring(l.getSessionRingName()); err != nil {
// Same justification as in standart_init_linux.go as to why we
// don't bail on ENOSYS.
//
// TODO(cyphar): And we should have logging here too.
if errors.Cause(err) != unix.ENOSYS {
return errors.Wrap(err, "join session keyring")
}
}
}
if l.config.CreateConsole {
if err := setupConsole(l.consoleSocket, l.config, false); err != nil {
return err
}
if err := system.Setctty(); err != nil {
return err
}
}
if l.config.NoNewPrivileges {
if err := unix.Prctl(unix.PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0); err != nil {
return err
}
}
// Without NoNewPrivileges seccomp is a privileged operation, so we need to
// do this before dropping capabilities; otherwise do it as late as possible
// just before execve so as few syscalls take place after it as possible.
if l.config.Config.Seccomp != nil && !l.config.NoNewPrivileges {
if err := seccomp.InitSeccomp(l.config.Config.Seccomp); err != nil {
return err
}
}
if err := finalizeNamespace(l.config); err != nil {
return err
}
if err := apparmor.ApplyProfile(l.config.AppArmorProfile); err != nil {
return err
}
if err := label.SetProcessLabel(l.config.ProcessLabel); err != nil {
return err
}
// Set seccomp as close to execve as possible, so as few syscalls take
// place afterward (reducing the amount of syscalls that users need to
// enable in their seccomp profiles).
if l.config.Config.Seccomp != nil && l.config.NoNewPrivileges {
if err := seccomp.InitSeccomp(l.config.Config.Seccomp); err != nil {
return newSystemErrorWithCause(err, "init seccomp")
}
}
return system.Execv(l.config.Args[0], l.config.Args[0:], os.Environ())
}