Generate and load custom docker profile for apparmor

Docker-DCO-1.1-Signed-off-by: Guillaume J. Charmes <guillaume.charmes@docker.com> (github: creack)

apparmor/setup.go

@@ -0,0 +1,98 @@
+package apparmor
+
+import (
+	"fmt"
+	"io/ioutil"
+	"os"
+	"os/exec"
+)
+
+const DefaultProfilePath = "/etc/apparmor.d/docker"
+const DefaultProfile = `
+# AppArmor profile from lxc for containers.
+@{HOME}=@{HOMEDIRS}/*/ /root/
+@{HOMEDIRS}=/home/
+#@{HOMEDIRS}+=
+@{multiarch}=*-linux-gnu*
+@{PROC}=/proc/
+
+profile docker-default flags=(attach_disconnected,mediate_deleted) {
+  network,
+  capability,
+  file,
+  umount,
+  dbus,
+
+  # 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() error {
+	if !IsEnabled() {
+		return nil
+	}
+
+	// If the profile already exists, let it be.
+	if _, err := os.Stat(DefaultProfilePath); err == nil {
+		return nil
+	}
+
+	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
+}