# Copyright 2021 The Chromium OS Authors. All rights reserved.
# Use of this source code is governed by a BSD-style license that can be
# found in the LICENSE file.

description "Bluetooth Manager"
author "ChromeOS BT <chromeos-bt-team@google.com>"

start on started system-services
stop on stopping system-services

# Limit respawning in case of crashloop
respawn limit 10 5
respawn

# This daemon manages the Bluetooth controllers on a system. It can be killed at
# the cost of an interruption in Bluetooth connectivity.
oom score -100

script
  # -u bluetooth changes user.
  # -g bluetooth changes group.
  # -G inherit bluetooth's supplementary groups.
  # -n prevents that execve gains privileges, required for seccomp filters.
  # -l creates IPC namespace (isolates System V IPC objects/POSIX message
  #    queues).
  # --uts enters a new UTS namespace.
  # -e enters new network namespace.
  # --profile minimalistic-mountns sets up minimalistic mount namespace.
  #   equivalent to -v -t -r --mount-dev -P /var/empty -b / -b /proc -b /dev/log
  # -k /run,/run,tmpfs,... mounts tmpfs at /run
  # -k /var,/var,tmpfs,... mounts tmpfs at /var
  # -k /sys,/sys,tmpfs... mounts tmpfs at /sys
  # -b /run/dbus mount read-only, required for D-Bus.
  # -b /sys/class/bluetooth mount read-only, required for hci devices.
  # -b /var/run/bluetooth mount read-only, required for pid files.
  # -b /var/lib/misc/ allows read-write access to select floss/bluez daemon
  # -b /var/lib/bluetooth/ allows read-write access to bluetooth config
  exec minijail0 \
  -u bluetooth -g bluetooth -G -n -l --uts -e \
  --profile minimalistic-mountns \
  -k '/run,/run,tmpfs,MS_NODEV|MS_NOEXEC|MS_NOSUID,mode=755,size=10M' \
  -k '/var,/var,tmpfs,MS_NODEV|MS_NOEXEC|MS_NOSUID,mode=755,size=10M' \
  -k '/sys,/sys,tmpfs,MS_NODEV|MS_NOEXEC|MS_NOSUID,mode=755,size=10M' \
  -b /run/dbus \
  -b /sys/class/bluetooth \
  -b /var/run/bluetooth \
  -b /var/lib/misc,,1 \
  -b /var/lib/bluetooth,,1 \
  -- /usr/bin/btmanagerd
end script