#!/bin/bash
#
# .---.                  .              .
# |                      |              |
# |--- .--. .-.  .-.  .-.|  .-. .--.--. |.-.  .-. .--.  .-.
# |    |   (.-' (.-' (   | (   )|  |  | |   )(   )|  | (.-'
# '    '     --'  --'  -' -  -' '  '   -' -'   -' '   -  --'
#
#                    Freedom in the Cloud
#
# Used to enable or disable batman mesh protocol on wlanX
#
# License
# =======
#
# Copyright (C) 2015-2016 Bob Mottram <bob@robotics.uk.to>
#
# This program is free software: you can redistribute it and/or modify
# it under the terms of the GNU Affero General Public License as published by
# the Free Software Foundation, either version 3 of the License, or
# (at your option) any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU Affero General Public License for more details.
#
# You should have received a copy of the GNU Affero General Public License
# along with this program.  If not, see <http://www.gnu.org/licenses/>.

PROJECT_NAME='freedombone'
COMPLETION_FILE=/root/${PROJECT_NAME}-completed.txt

if [[ $1 == "start" ]]; then
	# install avahi
	sed -i "s|#host-name=.*|host-name=$(hostname)|g" /etc/avahi/avahi-daemon.conf
	sed -i "s|host-name=.*|host-name=$(hostname)|g" /etc/avahi/avahi-daemon.conf
	sed -i "s|use-ipv4=.*|use-ipv4=yes|g" /etc/avahi/avahi-daemon.conf
	sed -i "s|use-ipv6=.*|use-ipv6=no|g" /etc/avahi/avahi-daemon.conf
	sed -i "s|#disallow-other-stacks=.*|disallow-other-stacks=yes|g" /etc/avahi/avahi-daemon.conf
	sed -i "s|hosts:.*|hosts:          files mdns4_minimal dns mdns4 mdns|g" /etc/nsswitch.conf
fi

# Mesh definition
WIFI_SSID=
if ! grep -q "WIFI_SSID:" $COMPLETION_FILE; then
	WIFI_SSID='mesh'
else
	WIFI_SSID=$(cat $COMPLETION_FILE | grep "WIFI_SSID:" | awk -F ':' '{print $2}')
fi
sed -i "s|WIFI_SSID:.*|WIFI_SSID:${WIFI_SSID}|g" $COMPLETION_FILE

CELLID='any'

CHANNEL=
if ! grep -q "Wifi channel:" $COMPLETION_FILE; then
	CHANNEL=2
else
	CHANNEL=$(cat $COMPLETION_FILE | grep "Wifi channel:" | awk -F ':' '{print $2}')
fi
sed -i "s|Wifi channel:.*|Wifi channel:${CHANNEL}|g" $COMPLETION_FILE

ZERONET_PORT=15441
IPFS_PORT=4001

# Ethernet bridge definition (bridged to bat0)
BRIDGE=br-mesh
IFACE='wlan0'
EIFACE=eth0

if [[ $IFACE == "wlan0" ]]; then
	if grep -q "wlan1" /proc/net/dev; then
		IFACE=wlan1
	fi
fi
if [[ $IFACE == "wlan0" ]]; then
	if grep -q "wlan2" /proc/net/dev; then
		IFACE=wlan2
	fi
fi
if [[ $IFACE == "wlan0" ]]; then
	if grep -q "wlan3" /proc/net/dev; then
		IFACE=wlan3
	fi
fi

if [ -e /etc/default/batctl ]; then
	. /etc/default/batctl
fi

function status {
	batctl o
}

function stop {
	if [ -z "$IFACE" ]; then
		echo 'error: unable to find wifi interface, not enabling batman-adv mesh'
		return
	fi
	if [ "$EIFACE" ]; then
		brctl delif $BRIDGE bat0
		brctl delif $BRIDGE $EIFACE
		ifconfig $BRIDGE down || true
		brctl delbr $BRIDGE
		ifconfig $EIFACE down -promisc
	fi

	avahi-autoipd -k $BRIDGE
	avahi-autoipd -k $IFACE
	ifconfig bat0 down -promisc

	batctl if del $IFACE
	rmmod batman-adv
	ifconfig $IFACE mtu 1500
	ifconfig $IFACE down
	iwconfig $IFACE mode managed

	iptables -D INPUT -p tcp --dport 548 -j ACCEPT
	iptables -D INPUT -p udp --dport 548 -j ACCEPT
	iptables -D INPUT -p tcp --dport 5353 -j ACCEPT
	iptables -D INPUT -p udp --dport 5353 -j ACCEPT
	iptables -D INPUT -p tcp --dport 5354 -j ACCEPT
	iptables -D INPUT -p udp --dport 5354 -j ACCEPT
	iptables -D INPUT -p tcp --dport $ZERONET_PORT -j ACCEPT
	iptables -D INPUT -p udp --dport $ZERONET_PORT -j ACCEPT
	iptables -D INPUT -p tcp --dport $IPFS_PORT -j ACCEPT

	systemctl restart network-manager
}

function verify {
	tempfile="$(mktemp)"
	batctl o > $tempfile
	if grep -q "disabled" $tempfile; then
		echo $'B.A.T.M.A.N. not enabled'
		rm $tempfile
		stop
		exit 726835
	fi
	echo $'B.A.T.M.A.N. is running'
	rm $tempfile
}

function start {
	if [ -z "$IFACE" ] ; then
		echo 'error: unable to find wifi interface, not enabling batman-adv mesh'
		exit 723657
	fi
	echo "info: enabling batman-adv mesh network $WIFI_SSID on $IFACE"

	systemctl stop network-manager
	sleep 5

	# remove an avahi service which isn't used
	if [ -f /etc/avahi/services/udisks.service ]; then
		sudo rm /etc/avahi/services/udisks.service
	fi

	# Might have to re-enable wifi
	rfkill unblock $(rfkill list|awk -F: "/phy/ {print $1}") || true

	ifconfig $IFACE down
	ifconfig $IFACE mtu 1532
	iwconfig $IFACE enc off
	iwconfig $IFACE mode ad-hoc essid $WIFI_SSID channel $CHANNEL
	sleep 1
	iwconfig $IFACE ap $CELLID

	modprobe batman-adv
	batctl if add $IFACE
	ifconfig $IFACE up
	avahi-autoipd --force-bind --daemonize --wait $BRIDGE
	avahi-autoipd --force-bind --daemonize --wait $IFACE
	ifconfig bat0 up promisc

	#Use persistent HWAddr
	ether_new=$(ifconfig eth0 | grep HWaddr | sed -e "s/.*HWaddr //")
	if [ ! -f /var/lib/mesh-node/bat0 ]; then
		mkdir /var/lib/mesh-node
		echo "${ether_new}" > /var/lib/mesh-node/bat0
	else
		ether=$(cat /var/lib/mesh-node/bat0)
		ifconfig bat0 hw ether ${ether}
	fi

	if [ "$EIFACE" ] ; then
		brctl addbr $BRIDGE
		brctl addif $BRIDGE bat0
		brctl addif $BRIDGE $EIFACE
		ifconfig bat0 0.0.0.0
		ifconfig $EIFACE 0.0.0.0
		ifconfig $EIFACE up promisc
		ifconfig $BRIDGE up
	fi

	iptables -A INPUT -p tcp --dport 548 -j ACCEPT
	iptables -A INPUT -p udp --dport 548 -j ACCEPT
	iptables -A INPUT -p tcp --dport 5353 -j ACCEPT
	iptables -A INPUT -p udp --dport 5353 -j ACCEPT
	iptables -A INPUT -p tcp --dport 5354 -j ACCEPT
	iptables -A INPUT -p udp --dport 5354 -j ACCEPT
	iptables -A INPUT -p tcp --dport $ZERONET_PORT -j ACCEPT
	iptables -A INPUT -p udp --dport $ZERONET_PORT -j ACCEPT
	iptables -A INPUT -p tcp --dport $IPFS_PORT -j ACCEPT

	systemctl restart avahi-daemon

	verify
}

if ! grep -q "$IFACE" /proc/net/dev; then
	echo 'Interface $IFACE was not found'
	stop
	exit 1
fi

case "$1" in
	start|stop|status)
		$1
		;;
	restart)
		stop
		sleep 10
		start
		;;
	ping)
		batctl ping $2
		;;
	ls|list)
		avahi-browse -atl
		;;
	*)
		echo "error: invalid parameter $1"
		echo 'usage: $0 {start|stop|restart|status|ping|ls|list}'
		exit 2
		;;
esac
exit 0
