latent.sh

#!/bin/bash   

### BEGIN INIT INFO
# Provides:          rtorrent 
# Required-Start:    $remote_fs $syslog
# Required-Stop:     $remote_fs $syslog
# Default-Start:     2 3 4 5
# Default-Stop:      0 1 6
# Short-Description: Start daemon at boot time
# Description:       Enable service provided by daemon.
### END INIT INFO

# Settings
PATH="/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin"
USER="WHOAMI"
RTORRENT=/usr/bin/rtorrent
BYOBU=/usr/bin/byobu
BYOBU_NAME=secure
BYOBU_TITLE=rtorrent
IP=/sbin/ip
PIDFILE=/var/run/rtorrent.pid
SOCKET=/tmp/rpc.socket
IFACE="eth0"
NETNS="hidden"
VETH0="veth0"
VETH1="veth1"
DNS="nameserver 91.239.100.100"
OPVN=/etc/openvpn/openvpn.ovpn
SOCKET_NAME=rtmux

remove_socket() {
    
    # Check if rpc socket exists and if it exists delete it.
    if [[ -e $SOCKET ]]; then
        rm -f $SOCKET
    fi
}

create_netns() {
    
    # Create namespace
    ip netns add ${NETNS}
    echo "Setting up ${NETNS}..."
    sleep 2
    
    # Bring loopback up
    ip netns exec ${NETNS} ip addr add 127.0.0.1/8 dev lo
    ip netns exec ${NETNS} ip link set lo up
    echo "Bringing up loopback device for ${NETNS}..."
    
    # Connect tubes from a to b
    ip link add ${VETH0} type veth peer name ${VETH1}
    ip link set ${VETH0} up
    ip link set ${VETH1} netns ${NETNS} up
    ip addr add 10.0.5.1/24 dev ${VETH0}
    echo "Connecting virtual circuits..."

    # Add default route
    ip netns exec ${NETNS} ip addr add 10.0.5.2/24 dev ${VETH1}
    ip netns exec ${NETNS} ip route add default via 10.0.5.1 dev ${VETH1}
    echo "Configuring default ip and route..."

    # Add DNS, can be changed in settings
    mkdir -p /etc/netns/${NETNS}
    touch /etc/netns/${NETNS}/resolv.conf # probably redundant 
    echo "$DNS" > /etc/netns/${NETNS}/resolv.conf
    echo "Setting up ${DNS}..."

    # IPTABLES
    iptables -A INPUT \! -i ${VETH0} -s 10.0.5.0/24 -j DROP
    iptables -t nat -A POSTROUTING -s 10.0.5.0/24 -o ${IFACE} -j MASQUERADE
    sysctl -q net.ipv4.ip_forward=1
    echo "Configuring iptables on ${IFACE}..."
    sleep 5
}


remove_netns() {
    
    # Removes network namespace    
    if [[ -e /etc/netns/${NETNS} ]]; then
        rm -f /etc/netns/${NETNS}
        iptables -D INPUT \! -i ${VETH0} -s 10.0.5.0/24 -j DROP
        iptables -t nat -D POSTROUTING -s 10.0.5.0/24 -o ${IFACE} -j MASQUERADE
        ip netns delete ${NETNS}
        sysctl -q net.ipv4.ip_forward=0
        echo "Restoring iptables on ${IFACE}..."
        sleep 3
    fi
}


connect_openvpn() {
    
    # You have to add 'daemon' to the end of *.opvn conf file to make it fork to background. 
    ip netns exec ${NETNS} openvpn --config "$OPVN"
    echo "Connection to VPN provider established."
	sleep 10
    
}

get_valid_ip() {
    
    # takes @params tun0,eth0
    VALIDIP=$(ip netns exec ${NETNS} ip addr ls "$1" | awk '/inet / {print $2}' | cut -d "/" -f1)
    echo "Connected IP: ${VALIDIP}"
    
}

case "$1" in
    
    # Start rtorrent in the background.
    start)
        create_netns
        connect_openvpn
		get_valid_ip tun0
        start-stop-daemon --start --pidfile ${PIDFILE} --make-pidfile \
            --exec ${IP} -- netns exec ${NETNS} sudo --user=${USER} \
		-H ${BYOBU} -L "${SOCKET_NAME}" new-session -d -s "${BYOBU_TITLE}" -n "${BYOBU_NAME}" "${RTORRENT} -b ${VALIDIP}"
        if [[ $? -ne 0 ]]; then
            echo "Error: rtorrent failed to start."
            exit 1
        fi
        echo "rtorrent started successfully."
        ;;

    # Stop rtorrent.
    stop)
        echo "Stopping rtorrent."
        start-stop-daemon --stop --pidfile ${PIDFILE}
        if [[ $? -ne 0 ]]; then
            echo "Error: failed to stop rtorrent process."
            exit 1
        fi

        # Tear down everything
        echo "Stopping byobu."
        killall byobu
        echo "Stopping openvpn."
        killall openvpn
	killall tmux
        remove_netns
        remove_socket

        echo "rtorrent stopped successfully."
        ;;

    # Restart rtorrent.
    restart)
        "$0" stop
        sleep 5
        "$0" start || exit 1
        ;;

    # Print usage information if the user gives an invalid option.
    *)
        echo "Usage: $0 [start|stop|restart]"
        exit 1
        ;;

esac