#!/bin/bash
#  _____               _           _
# |   __|___ ___ ___ _| |___ _____| |_ ___ ___ ___
# |   __|  _| -_| -_| . | . |     | . | . |   | -_|
# |__|  |_| |___|___|___|___|_|_|_|___|___|_|_|___|
#
#                              Freedom in the Cloud
#
# Used to enable or disable batman mesh protocol on a given interface
#
# License
# =======
#
# Copyright (C) 2015-2018 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}"

# The type of interface which the mesh will run on
MESH_INTERFACE_TYPE='wlan'

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

function status {
    batctl o

    if grep -q "bmx6" "$MESH_CURRENT_PROTOCOL"; then
        bmx6 -c show=originators
    fi
    if grep -q "bmx7" "$MESH_CURRENT_PROTOCOL"; then
        bmx7 -c show=originators
    fi
}

function stop {
    if [ ! -f "$MESH_CURRENT_PROTOCOL" ]; then
        return
    fi

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

    systemctl stop bmx6
    systemctl stop bmx7
    systemctl stop olsr2
    systemctl stop babel
    systemctl disable bmx6
    systemctl disable bmx7
    systemctl disable olsr2
    systemctl disable babel
    systemctl stop dnsmasq
    systemctl disable dnsmasq

    # shellcheck disable=SC2153
    if [ "$EIFACE" ]; then
        if [[ "$EIFACE" != "$IFACE" ]] ; then
            brctl delif "$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
    fi

    ifconfig bat0 down -promisc

    batctl if del "$IFACE"
    ifconfig "$IFACE" mtu 1500
    ifconfig "$IFACE" down
    if [[ "$MESH_INTERFACE_TYPE" == 'wlan'* ]]; then
        iwconfig "$IFACE" mode managed
    fi

    if [ "$IFACE_SECONDARY" ]; then
        systemctl stop hostapd
        systemctl disable hostapd
        batctl if del "$IFACE_SECONDARY"
        ifconfig "$IFACE_SECONDARY" mtu 1500
        ifconfig "$IFACE_SECONDARY" down
        if [[ "$MESH_INTERFACE_TYPE" == 'wlan'* ]]; then
            iwconfig "$IFACE_SECONDARY" mode managed
        fi
    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 $peermac"
    if [[ "$MESH_INTERFACE_TYPE" == 'wlan'* ]]; then
        iwconfig "$ifname" enc off
        iwconfig "$ifname" mode "$ifmode" essid "$ifssid" channel "$ifchannel"
    fi

    batctl if add "$ifname"
    ifconfig "$ifname" up
}

# shellcheck disable=SC2120
function start {
    update_wifi_adaptors "${MESH_INTERFACE_TYPE}"

    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"

    stop
    systemctl stop network-manager
    sleep 5

    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 [[ "$MESH_INTERFACE_TYPE" == 'wlan'* ]]; then
        if [ "$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
    fi

    modprobe batman-adv

    # avahi on ipv6
    sed -i 's|use-ipv4=.*|use-ipv4=no|g' /etc/avahi/avahi-daemon.conf
    sed -i 's|use-ipv6=.*|use-ipv6=yes|g' /etc/avahi/avahi-daemon.conf

    sed -i "s|ExecStart=.*|ExecStart=/usr/sbin/bmx6 dev=${IFACE}|g" /etc/systemd/system/bmx6.service
    sed -i "s|ExecStart=.*|ExecStart=/usr/sbin/bmx7 dev=${IFACE}|g" /etc/systemd/system/bmx7.service
    sed -i "s|ExecStart=.*|ExecStart=/usr/local/sbin/olsrd2_static ${IFACE}|g" /etc/systemd/system/olsr2.service
    sed -i "s|ExecStart=.*|ExecStart=/usr/local/bin/babeld ${IFACE}|g" /etc/systemd/system/babel.service
    systemctl daemon-reload

    add_wifi_interface "$IFACE" "$WIFI_SSID" ad-hoc "$CHANNEL"

    # 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 [ "$EIFACE" ] ; then
        if [[ "$EIFACE" != "$IFACE" ]] ; then
            ethernet_connected=$(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 internet bridge'

                sed -i "s|ExecStart=.*|ExecStart=/usr/sbin/bmx6 dev=${IFACE} dev=${EIFACE}|g" /etc/systemd/system/bmx6.service
                sed -i "s|ExecStart=.*|ExecStart=/usr/sbin/bmx7 dev=${IFACE} dev=${EIFACE}|g" /etc/systemd/system/bmx7.service
                sed -i "s|ExecStart=.*|ExecStart=/usr/local/sbin/olsrd2_static ${IFACE} ${EIFACE}|g" /etc/systemd/system/olsr2.service
                sed -i "s|ExecStart=.*|ExecStart=/usr/local/bin/babeld ${IFACE} ${EIFACE}|g" /etc/systemd/system/babel.service
                systemctl daemon-reload
            else
                echo $"$EIFACE is not connected"
            fi
        fi
    fi
    ifconfig "$BRIDGE" up
    dhclient "$BRIDGE"

    enable_mesh_seconary_wifi

    enable_mesh_firewall

    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

    if [ ! -f "$MESH_DEFAULT_PROTOCOL" ]; then
        echo 'bmx6' > "$MESH_DEFAULT_PROTOCOL"
    fi

    if grep -q "bmx6" "$MESH_DEFAULT_PROTOCOL"; then
        systemctl enable bmx6
        systemctl restart bmx6
        sed -i 's|<type>.*|<type>_bmx6._tcp</type>|g' /etc/avahi/services/routing.service
    fi

    if grep -q "bmx7" "$MESH_DEFAULT_PROTOCOL"; then
        systemctl enable bmx7
        systemctl restart bmx7
        sed -i 's|<type>.*|<type>_bmx7._tcp</type>|g' /etc/avahi/services/routing.service
    fi

    if grep -q "olsr" "$MESH_DEFAULT_PROTOCOL"; then
        IFACE=$(grep ExecStart "/etc/systemd/system/olsr2.service" | awk -F ' ' '{print $2}')
        mesh_generate_ipv6_address "$IFACE"

        systemctl enable olsr2
        systemctl restart olsr2
        sed -i 's|<type>.*|<type>_olsr2._tcp</type>|g' /etc/avahi/services/routing.service
    fi

    if grep -q "babel" "$MESH_DEFAULT_PROTOCOL"; then
        IFACE=$(grep ExecStart /etc/systemd/system/babel.service | awk -F ' ' '{print $2}')
        mesh_generate_ipv6_address "$IFACE"

        systemctl enable babel
        systemctl restart babel
        sed -i 's|<type>.*|<type>_babel._tcp</type>|g' /etc/avahi/services/routing.service
    fi

    systemctl restart avahi-daemon

    verify

    cat "$MESH_DEFAULT_PROTOCOL" > "$MESH_CURRENT_PROTOCOL"
}

function monitor {
    if [[ "$MESH_INTERFACE_TYPE" != 'wlan'* ]]; then
        return
    fi
    if [ -z "$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 ''

    # shellcheck disable=SC2119
    start
}

# optionally a file can contain the mesh interface type
mesh_interface_type_file=/root/.mesh_interface_type
if [ -f "$mesh_interface_type_file" ]; then
    MESH_INTERFACE_TYPE=$(head -n 1 < "$mesh_interface_type_file")
    if [[ "$MESH_INTERFACE_TYPE" == 'wlan'* ]]; then
        MESH_INTERFACE_TYPE='wlan'
    fi
    if [[ "$MESH_INTERFACE_TYPE" == 'eth'* ]]; then
        MESH_INTERFACE_TYPE='eth'
    fi
fi

mesh_protocol_init

if [[ "$MESH_INTERFACE_TYPE" == 'eth'* ]]; then
    MESH_INTERFACE_TYPE='eth'
fi

update_wifi_adaptors "${MESH_INTERFACE_TYPE}"

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

if [ -e /etc/default/batctl ]; then
    # shellcheck disable=SC1091
    . /etc/default/batctl
fi

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 ''
        # shellcheck disable=SC2119
        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