qubes-core-admin-linux/qrexec/qubes-rpc-multiplexer

#!/bin/sh

mkfifo /tmp/qrexec-rpc-stderr.$$
logger -t "$1-$2" -f /tmp/qrexec-rpc-stderr.$$ >/dev/null 2>&1 </dev/null &
exec 2>/tmp/qrexec-rpc-stderr.$$
rm -f /tmp/qrexec-rpc-stderr.$$

QUBES_RPC=/etc/qubes-rpc
LOCAL_QUBES_RPC=/usr/local/etc/qubes-rpc

if ! [ $# = 2 -o $# = 4 ] ; then
	echo "$0: bad argument count, usage: $0 SERVICE-NAME REMOTE-DOMAIN-NAME [REQUESTED_TARGET_TYPE REQUESTED_TARGET]" >&2
	exit 1
fi
export QREXEC_REQUESTED_TARGET_TYPE="$3"
if [ "$QREXEC_REQUESTED_TARGET_TYPE" = "name" ]; then
    export QREXEC_REQUESTED_TARGET="$4"
elif [ "$QREXEC_REQUESTED_TARGET_TYPE" = "keyword" ]; then
    export QREXEC_REQUESTED_TARGET_KEYWORD="$4"
fi
# else: requested target type unknown or not given, ignore
export QREXEC_REMOTE_DOMAIN="$2"
export QREXEC_SERVICE_FULL_NAME="$1"
SERVICE_WITHOUT_ARGUMENT="${1%%+*}"
if [ "${QREXEC_SERVICE_FULL_NAME}" != "${SERVICE_WITHOUT_ARGUMENT}" ]; then
    export QREXEC_SERVICE_ARGUMENT="${QREXEC_SERVICE_FULL_NAME#*+}"
fi

for CFG_FILE in $LOCAL_QUBES_RPC/"$1" $QUBES_RPC/"$1" \
        $LOCAL_QUBES_RPC/"${SERVICE_WITHOUT_ARGUMENT}" \
        $QUBES_RPC/"${SERVICE_WITHOUT_ARGUMENT}"; do
	if [ -s "$CFG_FILE" ]; then
        break
	fi
done

if [ -x "$CFG_FILE" ] ; then
	exec "$CFG_FILE" ${QREXEC_SERVICE_ARGUMENT}
	echo "$0: failed to execute handler for" "$1" >&2
	exit 1
else
	exec /bin/sh -- "$CFG_FILE" ${QREXEC_SERVICE_ARGUMENT}
	echo "$0: failed to execute handler for" "$1" >&2
	exit 1
fi