#!/usr/bin/env bash
# Copyright 2016, Rackspace US, Inc.
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
#     http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.

# NOTICE:
# When running in an AIO, we need to drop the following iptables rule in any
# neutron_agent containers to that ensure instances can communicate with the
# neutron metadata service. This is necessary because in an AIO environment
# there are no physical interfaces involved in instance -> metadata requests,
# and this results in the checksums being incorrect.

# Iptables path, used for ipv4 firewall.
IPTABLES=$(which iptables)
if [ ! -z "${IPTABLES}" ]; then
    if ! ${IPTABLES} -C POSTROUTING -t mangle -p tcp --sport 80 -j CHECKSUM --checksum-fill 2> /dev/null; then
        ${IPTABLES} -A POSTROUTING -t mangle -p tcp --sport 80 -j CHECKSUM --checksum-fill
    fi
fi

# Ip6tables path, used for ipv6 firewall.
IP6TABLES=$(which ip6tables)
if [ ! -z "${IP6TABLES}" ]; then
    if ! ${IP6TABLES} -C POSTROUTING -t mangle -p udp --sport 80 -j CHECKSUM --checksum-fill 2> /dev/null; then
        ${IP6TABLES} -A POSTROUTING -t mangle -p udp --sport 80 -j CHECKSUM --checksum-fill
    fi
fi