runc/apparmor/setup.go

129 lines
3.5 KiB
Go

package apparmor
import (
"fmt"
"io"
"io/ioutil"
"os"
"os/exec"
"path"
)
const (
DefaultProfilePath = "/etc/apparmor.d/docker"
)
const DefaultProfile = `
# AppArmor profile from lxc for containers.
#include <tunables/global>
profile docker-default flags=(attach_disconnected,mediate_deleted) {
#include <abstractions/base>
network,
capability,
file,
umount,
# ignore DENIED message on / remount
deny mount options=(ro, remount) -> /,
# allow tmpfs mounts everywhere
mount fstype=tmpfs,
# allow mqueue mounts everywhere
mount fstype=mqueue,
# allow fuse mounts everywhere
mount fstype=fuse.*,
# allow bind mount of /lib/init/fstab for lxcguest
mount options=(rw, bind) /lib/init/fstab.lxc/ -> /lib/init/fstab/,
# deny writes in /proc/sys/fs but allow binfmt_misc to be mounted
mount fstype=binfmt_misc -> /proc/sys/fs/binfmt_misc/,
deny @{PROC}/sys/fs/** wklx,
# allow efivars to be mounted, writing to it will be blocked though
mount fstype=efivarfs -> /sys/firmware/efi/efivars/,
# block some other dangerous paths
deny @{PROC}/sysrq-trigger rwklx,
deny @{PROC}/mem rwklx,
deny @{PROC}/kmem rwklx,
deny @{PROC}/sys/kernel/[^s][^h][^m]* wklx,
deny @{PROC}/sys/kernel/*/** wklx,
# deny writes in /sys except for /sys/fs/cgroup, also allow
# fusectl, securityfs and debugfs to be mounted there (read-only)
mount fstype=fusectl -> /sys/fs/fuse/connections/,
mount fstype=securityfs -> /sys/kernel/security/,
mount fstype=debugfs -> /sys/kernel/debug/,
deny mount fstype=debugfs -> /var/lib/ureadahead/debugfs/,
mount fstype=proc -> /proc/,
mount fstype=sysfs -> /sys/,
deny /sys/[^f]*/** wklx,
deny /sys/f[^s]*/** wklx,
deny /sys/fs/[^c]*/** wklx,
deny /sys/fs/c[^g]*/** wklx,
deny /sys/fs/cg[^r]*/** wklx,
deny /sys/firmware/efi/efivars/** rwklx,
deny /sys/kernel/security/** rwklx,
mount options=(move) /sys/fs/cgroup/cgmanager/ -> /sys/fs/cgroup/cgmanager.lower/,
# the container may never be allowed to mount devpts. If it does, it
# will remount the host's devpts. We could allow it to do it with
# the newinstance option (but, right now, we don't).
deny mount fstype=devpts,
}
`
func InstallDefaultProfile(backupPath string) error {
if !IsEnabled() {
return nil
}
// If the profile already exists, check if we already have a backup
// if not, do the backup and override it. (docker 0.10 upgrade changed the apparmor profile)
// see gh#5049, apparmor blocks signals in ubuntu 14.04
if _, err := os.Stat(DefaultProfilePath); err == nil {
if _, err := os.Stat(backupPath); err == nil {
// If both the profile and the backup are present, do nothing
return nil
}
// Make sure the directory exists
if err := os.MkdirAll(path.Dir(backupPath), 0755); err != nil {
return err
}
// Create the backup file
f, err := os.Create(backupPath)
if err != nil {
return err
}
defer f.Close()
src, err := os.Open(DefaultProfilePath)
if err != nil {
return err
}
defer src.Close()
if _, err := io.Copy(f, src); err != nil {
return err
}
}
// Make sure /etc/apparmor.d exists
if err := os.MkdirAll(path.Dir(DefaultProfilePath), 0755); err != nil {
return err
}
if err := ioutil.WriteFile(DefaultProfilePath, []byte(DefaultProfile), 0644); err != nil {
return err
}
output, err := exec.Command("/lib/init/apparmor-profile-load", "docker").CombinedOutput()
if err != nil {
return fmt.Errorf("Error loading docker profile: %s (%s)", err, output)
}
return nil
}