#!/bin/sh

# ---------------------------------------------------------------------------
# MODIFY THESE PARAMETERS TO SUIT
# ---------------------------------------------------------------------------

# How often to test for inactivity
g_samplerate=90

# If only a few bytes are received you may still want to disconnect.
# Specify the number of bytes per minute here.
g_dontcountbytespermin=5000

# Don't auto disconnect for the listed interfaces in g_disable
# Effectively disables this script:
#g_disable="wlan gprs"
# Disable for gprs:
#g_disable="gprs"
# Disable for wlan:
#g_disable="wlan"
# Disconnect enabled for wlan and gprs:
g_disable=

# Enable logging
#g_logging="true"
g_logging="false"

# Where to store the logfile. This is cleared when it goes over 100k.
logfile=/root/autodisconnect.log

# ---------------------------------------------------------------------------
# DON'T MODIFY ANYTHING BELOW THIS POINT
# ---------------------------------------------------------------------------

# ---------------------------------------------------------------------------
# GLOBALS
# ---------------------------------------------------------------------------

# Never drop openvpn. Iface is just a heading therefore not real.
g_disable="Iface tun "$g_disable

# Number of bytes to ignore for each time period
g_dontcountbytes=$((g_dontcountbytespermin*g_samplerate/60))

# ---------------------------------------------------------------------------
# FUNCTIONS
# ---------------------------------------------------------------------------

# ---------------------------------------------------------------------------
init()
# ---------------------------------------------------------------------------
{
    # Allow dbus to work
    [[ -e /tmp/dbus-info ]] && eval `cat /tmp/dbus-info`

    export DBUS_SESSION_BUS_ADDRESS \
           DBUS_SESSION_BUS_PID \
           DBUS_SESSION_BUS_WINDOWID

    # Don't let log file get too big
    if [[ -w "$logfile" ]]; then
        size=`stat $logfile | grep Size | awk '{ print $2; }'`
        [[ "$size" -gt 100000 ]] && :>$logfile
    fi
}

# ---------------------------------------------------------------------------
logentry()
# ---------------------------------------------------------------------------
# Send a string to this function to append it to the log file
#
# Arg 1 - The text to log
{
    [[ "$g_logging" == "true" ]] && {
        echo -e "`date` $1" >> $logfile
        echo "`date` $1"
    }
}

# ---------------------------------------------------------------------------
osnotify()
# ---------------------------------------------------------------------------
# Send a string to this function to generate a system popup
#
# Arg 1 - The text to display
{
    /usr/bin/dbus-send --type=method_call \
        --dest=org.freedesktop.Notifications \
        /org/freedesktop/Notifications \
        org.freedesktop.Notifications.SystemNoteInfoprint \
        string:"$1"
}

# ---------------------------------------------------------------------------
disconnect()
# ---------------------------------------------------------------------------
# Disconnect current connection
#
# No args
{
    dbus-send --system --dest=com.nokia.icd \
        /com/nokia/icd_ui \
        com.nokia.icd_ui.disconnect \
        boolean:true
}

# ---------------------------------------------------------------------------
disable_quit()
# ---------------------------------------------------------------------------
{
    # Disable for some interfaces
    [[ -n "$g_disable" ]] && {
        if echo "$g_disable" | grep -qs "$interface" 2>/dev/null; then
            #osnotify "Auto-disconnect disabled for $interface"
            logentry "Auto-disconnect disabled for $interface"
            exit 0
        else
            osnotify "Auto-disconnect enabled for $interface"
            logentry "Auto-disconnect enabled for $interface"
        fi
    }
}

# ---------------------------------------------------------------------------
main()
# ---------------------------------------------------------------------------
# Main entry point
{
    init

    # Log monitor startup to file & notify user via popup
    logentry "Auto-disconnect starting"
    interface=`grep -v tun /proc/net/route | tail -1 | cut -f1 | tr -d 0-9`
    logentry "Current connection : $interface"

    # Quit if this interface is in the g_disable list
    disable_quit

    while true; do
        sleep $g_samplerate
        a=`grep -v tun /proc/net/route | tail -1 |cut -f1` 
        while [[ "$a" != "Iface" ]]; do
            b=`ifconfig $a | grep RX.b | cut -d"(" -f1 | cut -d: -f2`
            c=$b
            sleep $g_samplerate
            b=`ifconfig $a | grep RX.b | cut -d"(" -f1 | cut -d: -f2`
            a=`grep -v tun /proc/net/route | tail -1 |cut -f1`
            if [ "$a" == "Iface" ]; then
                osnotify "Auto-disconnect for $interface stopped."
                logentry "$interface lost. Quitting."
                exit 0
            fi
            if [ "$b" -lt "$((c+g_dontcountbytes))" -a "$a" != "Iface" ]; then
                disconnect
                osnotify "Connection $interface closed due to inactivity"
                logentry "$interface closed. Bytes received : $((b-c))"
                exit 0
            else
                logentry "$interface: Bytes received : $((b-c))"
            fi
        done
    done
}

# Start
main

exit 0

#!/bin/sh

AUTODISCONNECT=/usr/local/bin/autodisconnect

if [ ! -x $AUTODISCONNECT ]; then
  exit 0
fi

$AUTODISCONNECT

#!/bin/sh

AUTODISCONNECT=/usr/local/bin/autodisconnect

if [ ! -x $AUTODISCONNECT ]; then
  exit 0
fi

kill `pidof autodisconnect`