Bose-SoundTouch/scripts/on-device-install/aftertouch

#!/bin/sh
### BEGIN INIT INFO
# Provides:          aftertouch-service
# Required-Start:    $network $local_fs
# Required-Stop:     $network $local_fs
# Default-Start:     2 3 4 5
# Default-Stop:      0 1 6
# Short-Description: Run AfterTouch on this device
# Description:       Start/stop AfterTouch soundtouch-service
### END INIT INFO


NAME="aftertouch-service"
DESC="Bose AfterTouch service"
DAEMON="/opt/aftertouch/aftertouch-service"
PIDFILE="/var/run/$NAME.pid"
DATADIR="/opt/aftertouch/data"
CONFFILE="/opt/aftertouch/aftertouch.conf"
SCRIPTNAME="/etc/init.d/$NAME"
USER="root"
LOG_TAG="aftertouch"


# Export PATH
export PATH="/usr/local/sbin:/usr/local/bin:/sbin:/bin:/usr/sbin:/usr/bin"


# Optional settings written by install.sh (AFTERTOUCH_LAN_PORT, SERVICE_PORT),
# or added by hand for anything the daemon reads from its environment
# (SERVER_URL, MGMT_USERNAME, MGMT_PASSWORD, DEPLOYMENT_MODE, ...). `set -a`
# auto-exports every assignment while the file is sourced, so any such
# variable actually reaches the daemon -- it's forked from this same shell's
# environment further down via `--startas "/bin/sh" -- -c "... \"$DAEMON\" ..."`.
# Sourced before the defaults below so it can override either.
if [ -r "$CONFFILE" ]; then
  set -a
  # shellcheck source=/dev/null
  . "$CONFFILE"
  set +a
fi

# Port the daemon binds locally. Kept in one variable because it appears in
# the daemon arguments, the readiness poll and `status` -- three places that
# used to hardcode 8000 independently, so changing one silently broke the
# other two.
SERVICE_PORT="${SERVICE_PORT:-8000}"

# LAN entry port: a port number, "auto" (default), or "none".
LAN_PORT_MODE="${AFTERTOUCH_LAN_PORT:-auto}"

# This script only ever runs on the speaker itself, so the deployment mode is
# not a guess -- default it here (overridable via aftertouch.conf, though that
# should never be needed). Exported so soundtouch-service picks it up via
# DEPLOYMENT_MODE without needing a --deployment-mode flag threaded through
# the daemon invocation below.
export DEPLOYMENT_MODE="${DEPLOYMENT_MODE:-on-device}"


# Sanity check executable
test -x "$DAEMON" || {
  echo "ERROR: Cannot execute $DAEMON (check path and permissions)." >&2
  exit 1
}


# ---------------------------------------------------------------------------
# LAN entry-port redirect
#
# On chassis built around a BCO ("SMSC") Wi-Fi/Bluetooth co-processor,
# inbound LAN traffic only reaches this Linux SoC for a fixed set of Bose's
# own service ports, which appears to be compiled into the co-processor's
# firmware. AfterTouch's :8000 is not on that list, so a LAN client's SYN
# never arrives here at all -- confirmed on an ST20 (`spotty`), where
# `tcpdump -i eth0` on the speaker saw zero packets for :8000 while Bose's
# own :8090/:8091/:17000 answered normally from the same client. The usual
# suspects were all ruled out: the service does bind 0.0.0.0 correctly, the
# speaker's iptables is empty, and SSH over the same path works.
#
# Workaround: NAT one of the relayed Bose ports to ours. The default, 17008,
# is Bose's SoftwareUpdate listener -- its cloud is gone, so taking over its
# inbound traffic costs nothing real. Only external traffic is matched
# (`! -i lo`), so anything running on the speaker still reaches both the real
# service on loopback and AfterTouch on :8000 as before.
#
# Credit: the STR / SoundTouch Reborn project (github.com/JRpersonal/streborn)
# documented and shipped this REDIRECT technique first, using the same entry
# port for the same reason.
#
# Which models need this is tracked in
# docs/content/docs/reference/MODEL-SUPPORT-MATRIX.md.
# ---------------------------------------------------------------------------

# Resolve LAN_PORT_MODE into $LAN_PORT. Returns non-zero when no redirect
# should be installed.
lan_redirect_port() {
    case "$LAN_PORT_MODE" in
        none|off|disabled|0)
            return 1
            ;;
        auto|"")
            # Only auto-enable where direct LAN access is known not to work.
            # has-bco is Bose's own helper: [ "$(cat /proc/module_type)" = scm ]
            has-bco >/dev/null 2>&1 || return 1
            LAN_PORT=17008
            ;;
        *[!0-9]*)
            echo "WARNING: ignoring AFTERTOUCH_LAN_PORT='$LAN_PORT_MODE'; expected a port number, 'auto' or 'none'." >&2
            return 1
            ;;
        *)
            LAN_PORT="$LAN_PORT_MODE"
            ;;
    esac
    return 0
}

# Remove every PREROUTING rule pointing at our service port, whatever entry
# port it used, so changing AFTERTOUCH_LAN_PORT cannot orphan the old rule.
lan_redirect_purge() {
    iptables -t nat -S PREROUTING 2>/dev/null \
      | grep -- "--to-ports $SERVICE_PORT" \
      | sed 's/^-A /-D /' \
      | while read -r rule; do
            # shellcheck disable=SC2086
            iptables -t nat $rule 2>/dev/null || true
        done
}

lan_redirect_apply() {
    lan_redirect_port || return 0

    if ! iptables -t nat -L PREROUTING -n >/dev/null 2>&1; then
        echo "WARNING: this kernel has no iptables nat table; :$LAN_PORT was not" >&2
        echo "         redirected. Reach AfterTouch over an SSH tunnel instead." >&2
        return 0
    fi

    lan_redirect_purge

    # Safety net for a kernel whose iptables lacks -S (purge would no-op):
    # without this, every restart would stack another duplicate rule.
    if iptables -t nat -C PREROUTING ! -i lo -p tcp --dport "$LAN_PORT" \
         -j REDIRECT --to-ports "$SERVICE_PORT" 2>/dev/null; then
        echo "LAN access already active on port $LAN_PORT."
        return 0
    fi

    if iptables -t nat -I PREROUTING 1 ! -i lo -p tcp --dport "$LAN_PORT" \
         -j REDIRECT --to-ports "$SERVICE_PORT" 2>/dev/null; then
        echo "LAN access: port $LAN_PORT now reaches AfterTouch on :$SERVICE_PORT."
    else
        echo "WARNING: could not install the :$LAN_PORT -> :$SERVICE_PORT redirect." >&2
    fi
}

lan_redirect_remove() {
    lan_redirect_purge
}


case "$1" in
  start)
    echo "Starting $DESC..."

    mount -o remount,rw / >/dev/null 2>&1 || {
      echo "ERROR: remount failed." >&2
      exit 1
    }

    mkdir -p "$DATADIR"

    # Route stdout + stderr through `logger -t $LOG_TAG` so the
    # daemon's output lands in busybox syslog (bounded ring buffer,
    # never grows on disk). Users diagnose with:
    #
    #   logread        | grep aftertouch | tail -20
    #   logread -f     | grep aftertouch     # live tail
    #
    # This used to be a `--startas "/bin/sh" -- -c "exec $DAEMON | logger"`
    # pipeline, on the theory that `exec` replaces /bin/sh so --make-pidfile
    # records the daemon's own PID. That's wrong for a *piped* command:
    # POSIX requires each side of a pipe to run in its own forked process,
    # so the top-level /bin/sh forks two children (one execs into the
    # daemon, one becomes logger) and stays alive itself, blocked in
    # wait() -- --make-pidfile recorded *that* wrapper's PID, not the
    # daemon's. `stop` then killed the wrapper, which doesn't forward
    # SIGTERM to its children, orphaning the real daemon (reparented to
    # init) to keep running -- and keep holding :8000 -- forever, silently
    # surviving every later stop/start/restart.
    #
    # A first fix attempt dropped the wrapper shell entirely in favor of
    # `--exec "$DAEMON"` directly, with a plain shell-level `>FIFO`
    # redirection on the start-stop-daemon invocation. That broke logging
    # instead: this busybox's `--background` resets the backgrounded
    # child's own stdio, ignoring the outer redirection, so the daemon's
    # output never reached the FIFO -- confirmed on hardware (`logger`
    # exited immediately with nothing to read, `logread` showed nothing
    # new).
    #
    # This version keeps a wrapper shell -- its *own* FIFO redirection,
    # set up by its own script logic rather than inherited from outside,
    # isn't affected by whatever --background did to its stdio -- but has
    # the wrapper record the daemon's real PID itself instead of trusting
    # --make-pidfile. $! after a single, non-piped backgrounded command is
    # portably that command's own PID; --make-pidfile can only ever see
    # whatever process start-stop-daemon directly forked (the wrapper),
    # never a PID from inside it.
    LOGFIFO="/tmp/$NAME.fifo"
    rm -f "$LOGFIFO"
    mkfifo "$LOGFIFO"

    # --pidfile (without --make-pidfile, since the wrapper writes it itself
    # once it knows the daemon's real PID) makes start-stop-daemon's own
    # "already running?" check keyed on *our* pidfile, not on "/bin/sh"
    # identity. Without this, --startas "/bin/sh" is itself the match
    # criterion -- and since the wrapper stays alive for the daemon's whole
    # lifetime (blocked in its own `wait`), and `stop` only confirms the
    # *daemon* PID died (not that the wrapper has finished tearing down),
    # a `restart` firing `start` right after `stop` can catch the previous
    # wrapper still mid-teardown. start-stop-daemon then silently refuses
    # ("/bin/sh is already running", swallowed by --quiet) while the
    # script burns its full 120s timeout waiting for a daemon that was
    # never launched. Confirmed on hardware: a bare
    # `start-stop-daemon --startas "/bin/sh" -- -c "echo hi"` was refused
    # with exactly that message while a prior wrapper was still alive.
    start-stop-daemon --start \
        --quiet \
        --pidfile "$PIDFILE" \
        --background \
        --chuid "$USER" \
        --startas "/bin/sh" \
        -- -c "logger -t $LOG_TAG <'$LOGFIFO' & \"$DAEMON\" --data-dir '$DATADIR' --port '$SERVICE_PORT' --record-interactions=false --discovery-interval=60m >'$LOGFIFO' 2>&1 & echo \$! >'$PIDFILE'; wait"

    tries=0
    max_tries=60
    while [ $tries -lt $max_tries ]; do
        if curl -fsS "http://localhost:$SERVICE_PORT" >/dev/null 2>&1; then
          # Only once the service actually answers is it worth pointing LAN
          # traffic at it.
          lan_redirect_apply
          exit 0
        fi
        sleep 2
        tries=$((tries + 1))
    done

    echo "ERROR: daemon started but http://localhost:$SERVICE_PORT never responded within $((max_tries * 2))s." >&2
    echo "       Inspect the daemon's syslog output:" >&2
    echo "         logread | grep $LOG_TAG | tail -20" >&2
    exit 1
    ;;

  stop)
    echo "Stopping $DESC..."
    # Drop the LAN redirect first: leaving it in place while nothing listens
    # would silently blackhole the entry port.
    lan_redirect_remove
    if [ -f "$PIDFILE" ]; then
      PID=$(cat "$PIDFILE")
      start-stop-daemon --stop \
        --quiet \
        --oknodo \
        --pidfile "$PIDFILE"
      # Wait up to 15 s for SIGTERM to take effect before escalating.
      # The Go HTTP server exits promptly on SIGTERM in normal conditions;
      # the loop handles the rare case where it is stuck in a blocking syscall.
      tries=0
      while [ $tries -lt 15 ] && kill -0 "$PID" 2>/dev/null; do
        sleep 1
        tries=$((tries + 1))
      done
      if kill -0 "$PID" 2>/dev/null; then
        echo "Warning: $NAME (PID $PID) still alive after ${tries}s; sending SIGKILL..." >&2
        kill -9 "$PID" 2>/dev/null || true
        sleep 1
      fi
      rm -f "$PIDFILE"
    else
      echo "No $NAME running (no PID file)." >&2
    fi
    ;;

  restart|force-reload)
    "$0" stop
    sleep 2
    "$0" start
    ;;

  status)
    if [ -f "$PIDFILE" ]; then
      PID=$(cat "$PIDFILE")
      if kill -0 "$PID" 2>/dev/null; then
        # PID is alive — does it actually serve HTTP? A live process
        # with a dead listener is the symptom behind issue #250
        # (Gustour's ST30: status said running, curl said
        # connection-refused). Distinguish the two states here so
        # status isn't a false-positive.
        if curl -fsS --max-time 3 "http://localhost:$SERVICE_PORT" >/dev/null 2>&1; then
          echo "$NAME is running (PID $PID, http://localhost:$SERVICE_PORT responding)."
          if lan_redirect_port; then
            if iptables -t nat -C PREROUTING ! -i lo -p tcp --dport "$LAN_PORT" \
                 -j REDIRECT --to-ports "$SERVICE_PORT" 2>/dev/null; then
              echo "LAN access: reachable from other machines on port $LAN_PORT."
            else
              echo "LAN access: redirect for port $LAN_PORT is NOT installed." >&2
            fi
          fi
          exit 0
        else
          echo "$NAME PID $PID is alive but http://localhost:$SERVICE_PORT is not responding." >&2
          echo "Recent log:" >&2
          logread 2>/dev/null | grep "$LOG_TAG" | tail -10 >&2
          exit 3
        fi
      else
        echo "$NAME is not running (PID file exists but process is dead)." >&2
        exit 1
      fi
    else
      echo "$NAME is not running."
      exit 3
    fi
    ;;

  *)
    echo "Usage: $SCRIPTNAME {start|stop|restart|force-reload|status}"
    exit 1
    ;;
esac


exit 0