Notices

#!/bin/bash
# Finds the strongest unencrypted AP and tries to connect to it via dhcp
# Call this script like "wifi.sh wlan0"
echo hi

if [ `whoami` != "root" ];then
echo "Sorry, you need to be root to run this program"
exit 1
fi

interface=wlan0
ifconfig $interface up

# Proggy
while true
do
iwlist $interface scan > $TEMP
NumAPs=`cat $TEMP | grep ESSID | wc -l`
BestAP=0
BestQuality=-1
BestESSID=""
echo APs: $NumAPs
for i in `seq 1 $NumAPs`;
do
# Check if AP is encrypted
Encryption=`cat $TEMP | grep Encryption | head -n$i | tail -n1 | cut -d":" -f2`
if [ $Encryption = "off" ]; then
# Find AP with the highest quality
ESSID=`cat $TEMP | grep ESSID | head -n$i | tail -n1 | cut -d"\"" -f2`  
MODE=`cat $TEMP | grep Mode | head -n$BestAP | tail -n1 | cut -d":" -f2`
QUALITY=`cat $TEMP | grep Quality | head -n$i | tail -n1 | cut -d":" -f2 | cut -d"/" -f1 | sed 's/ //g'`
echo ESSID=$ESSID Mode=$MODE Quality=$QUALITY
if [ "$QUALITY" -gt "$BestQuality" ]; then
BestQuality=$QUALITY
BestAP=$i
BestESSID=$ESSID
fi
fi
done
if [ $BestAP -gt 0 ]; then
timeout 2 mplayer /usr/share/sounds/ui-new_email.wav > /dev/null 2>&1 &
# Yay, we found an unencrypted AP:
echo
#ESSID=`cat $TEMP | grep ESSID | head -n$BestAP | tail -n1 | cut -d"\"" -f2`
CHANNEL=`cat $TEMP | grep Channel | head -n$BestAP | tail -n1 | cut -d":" -f2 | sed 's/Channel //g' | sed 's/)//g'`
echo Connecting to \"$BestESSID\"  Channel $CHANNEL
echo
# Connect
iwconfig $interface essid "$BestESSID" channel $CHANNEL mode managed #$MODE 
sleep 3
iwconfig #2>&1 | grep ESSID
echo
if ping -c2 `udhcpc -i $interface -n -q 2>&1 | grep dns | cut -d" " -f3`
then
echo
ping -c 1 www.google.com
echo
echo very well
echo
read a
ifconfig $interface down
ifconfig $interface up
else
echo
echo bad
echo
ifconfig $interface down
ifconfig $interface up
fi
fi
done
# Cleanup