#!/bin/bash
#
# .---.                  .              .
# |                      |              |
# |--- .--. .-.  .-.  .-.|  .-. .--.--. |.-.  .-. .--.  .-.
# |    |   (.-' (.-' (   | (   )|  |  | |   )(   )|  | (.-'
# '    '     --'  --'  -' -  -' '  '   -' -'   -' '   -  --'
#
#                    Freedom in the Cloud
#
# Used to enable or disable batman mesh protocol on wlanX
#
# License
# =======
#
# Copyright (C) 2015-2017 Bob Mottram <bob@freedombone.net>
#
# 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

# hotspot passphrase must be 5 characters or longer
HOTSPOT_PASSPHRASE="${PROJECT_NAME}"

source /usr/share/${PROJECT_NAME}/utils/${PROJECT_NAME}-utils-wifi
source /usr/share/${PROJECT_NAME}/utils/${PROJECT_NAME}-utils-mesh

mesh_protocol_init
update_wifi_adaptors

if [ ! $IFACE ]; then
    echo $'No wlan adaptor'
    exit 0
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

    systemctl stop dnsmasq
    systemctl disable dnsmasq

    if [ "$EIFACE" ]; then
        brctl delif $BRIDGE bat0
        ifconfig $BRIDGE down || true
        ethernet_connected=$(cat /sys/class/net/$EIFACE/carrier)
        if [[ "$ethernet_connected" != "0" ]]; then
            systemctl stop hostapd
            brctl delif $BRIDGE $EIFACE
            ifconfig $EIFACE down -promisc
        fi
        brctl delbr $BRIDGE
    fi

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

    batctl if del $IFACE
    ifconfig $IFACE mtu 1500
    ifconfig $IFACE down
    iwconfig $IFACE mode managed

    if [ $IFACE_SECONDARY ]; then
        systemctl stop hostapd
        systemctl disable hostapd
        batctl if del $IFACE_SECONDARY
        ifconfig $IFACE_SECONDARY mtu 1500
        ifconfig $IFACE_SECONDARY down
        iwconfig $IFACE_SECONDARY mode managed
    fi

    rmmod batman-adv

    disable_mesh_firewall

    systemctl restart network-manager

    if [ -f $MESH_CURRENT_PROTOCOL ]; then
        rm $MESH_CURRENT_PROTOCOL
    fi
}

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 add_wifi_interface {
    ifname=$1
    ifssid=$WIFI_SSID
    if [ $2 ]; then
        ifssid=$2
    fi
    ifmode=ad-hoc
    if [ $3 ]; then
        ifmode=$3
    fi
    ifchannel=$CHANNEL
    if [ $4 ]; then
        ifchannel=$4
    fi

    ifconfig $ifname down
    ifconfig $ifname mtu 1532
    peermac=$(assign_peer_address)
    if [ ! $peermac ]; then
        echo $"Unable to obtain MAC address for $peermac on $ifname"
        return
    fi
    ifconfig $ifname hw ether $peermac
    echo $"$ifname assigned MAC address $peermac"
    iwconfig $ifname enc off
    iwconfig $ifname mode $ifmode essid $ifssid channel $ifchannel

    batctl if add $ifname
    ifconfig $ifname up
}

function start {
    update_wifi_adaptors

    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"

    mesh_protocol_stop

    systemctl stop network-manager
    sleep 5

    systemctl stop bmx6
    systemctl disable bmx6
    systemctl stop dnsmasq
    systemctl disable dnsmasq

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

    global_rate_limit

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

    secondary_wifi_available=
    if [ $IFACE_SECONDARY ]; then
        if [[ $IFACE != $IFACE_SECONDARY ]]; then
            if [ -d /etc/hostapd ]; then
                if [ ${#HOTSPOT_PASSPHRASE} -gt 4 ]; then
                    secondary_wifi_available=1
                else
                    echo $'Hotspot passphrase is too short'
                fi
            fi
        fi
    fi

    modprobe batman-adv

    add_wifi_interface $IFACE $WIFI_SSID ad-hoc $CHANNEL
    avahi-autoipd --force-bind --daemonize --wait $IFACE

    # NOTE: Don't connect the secondary wifi device. hostapd will handle that by itself

    ifconfig bat0 up promisc

    brctl addbr $BRIDGE
    brctl addif $BRIDGE bat0
    ifconfig bat0 0.0.0.0
    ethernet_connected='0'
    if [ "$EIFACE" ] ; then
        ethernet_connected=$(cat /sys/class/net/$EIFACE/carrier)
        if [[ "$ethernet_connected" != "0" ]]; then
            echo $'Trying ethernet bridge to the internet'
            brctl addif $BRIDGE $EIFACE
            ifconfig $EIFACE 0.0.0.0
            ifconfig $EIFACE up promisc
            echo $'End of ethernet bridge'
        else
            echo $"$EIFACE is not connected"
        fi
    fi
    ifconfig $BRIDGE up
    dhclient $BRIDGE

    enable_mesh_seconary_wifi

    enable_mesh_firewall

    systemctl restart avahi-daemon

    enable_mesh_scuttlebot
    enable_mesh_tor

    sed -i "s|server_name .*|server_name ${HOSTNAME}.local;|g" /etc/nginx/sites-available/git_ssb

    systemctl restart nginx

    verify

    echo "batman-adv" > $MESH_CURRENT_PROTOCOL
}

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

    clear
    echo ''
    echo $'*** Stopping network ***'
    echo ''

    stop

    echo "info: monitoring mesh network $WIFI_SSID on $IFACE"

    systemctl stop network-manager
    sleep 5

    clear
    echo ''
    echo $'*** Setting firewall rate limit ***'
    echo ''

    global_rate_limit

    clear
    echo ''
    echo $'*** Enabling wifi adaptor in monitor mode ***'
    echo ''

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

    ifconfig $IFACE down
    ifconfig $IFACE mtu 1532
    ifconfig $IFACE hw ether $(assign_peer_address)
    iwconfig $IFACE enc off
    iwconfig $IFACE mode monitor channel $CHANNEL
    sleep 1
    iwconfig $IFACE ap $CELLID

    modprobe batman-adv
    batctl if add $IFACE
    ifconfig $IFACE up

    horst -i $IFACE

    clear
    echo ''
    echo $'*** Restarting the network daemon. This may take a while. ***'
    echo ''

    start
}

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

case "$1" in
    start|stop|status|monitor)
        $1
        ;;
    restart)
        clear
        echo ''
        echo $'*** Stopping mesh network connection ***'
        echo ''
        stop
        sleep 10
        clear
        echo ''
        echo $'*** Starting mesh network connection ***'
        echo ''
        start
        ;;
    ping)
        batctl ping $2
        ;;
    data)
        watch -n1 "batctl s | grep mgmt | grep bytes"
        ;;
    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