wifi

#!/bin/bash
#	Copyright(c) 2012 RubytotheRails.com
#	This is free software distributed per the MIT License at www.r2dr.com/licenses/commands
#	Copyright and License URL must be included for any distribution

WIFIUTIL_VERSION=2.2
DIR=~/.wifi
mkdir $DIR 2>/dev/null
tmpfile=$DIR/.tmpfile

function clear_tmpfile {
	rm -f $tmpfile 2>/dev/null
}

function paint { echo $2; }
function colorOn { echo -n; }
function colorOff { echo -n; }
[[ -f $(dirname $0)/colorize ]] && source "$(dirname $0)/colorize"


function usage {
  echo "Wifi status"
  echo "Usage: wifi [COMMAND]"
  echo ""
  echo "  gateway [g]  return the gateway ip address"
  echo "  reload [r]   reload/refresh wifi driver (reset)"
  echo "  scan [s]     scan wifis"
  echo "  dns  [n]     retrieve name servers"
  echo "  others [o]   scan other users on the wlan"  
  echo "  dup [d]      check for duplicate ip on wlan"
  echo "  ip           wireless ip address"
  echo "  ping [p]     ping various associated IPs"
  echo "                  0) gateway, 1) dns1, 2) dns2..."
  echo "  check [c]    run connection diagnostic check"
  echo "  help [h]     help"
  echo ""
}
function color_usage {
	colorOn yellow
	usage
	colorOff
}

function gateway_ip {
  route -n | grep "^0.0.0.0" | tr -s ' ' | cut -f2 -d ' '
}

function wping {
  check_connected

  PING_IP=
  PING_INSTRUCTION=
  case $1 in
    1|dns1) PING_IP=`name_servers | sed -n 1p`; PING_INSTRUCTION=DNS1 ;;
    2|dns2) PING_IP=`name_servers | sed -n 2p`; PING_INSTRUCTION=DNS2 ;;
    *)
      PING_INSTRUCTION=GATEWAY
      PING_IP=`gateway_ip`
    ;;
  esac
  echo "Pinging $PING_INSTRUCTION address $PING_IP..."
  ping -n -c 4 -i 0.4 $PING_IP
}

function ifwireless {
  iw dev | grep -Po "Interface \K[^\s]+"
}

function signal {
  iwconfig `ifwireless` | grep -Po "Signal level=\K.*" | sed -re 's/\s+$//'
}

function bitrate {
	iwconfig `ifwireless` | grep -Po "Bit Rate=\K[0-9]+ Mb/s"
}

function linkquality {
  iwconfig `ifwireless` | grep -Po "Link Quality=\K[0-9]+/70" | awk '{printf "%.0f", ($0*100/70)}'
}

function essid {
  iwconfig `ifwireless` | grep -Po "ESSID:\"\K[^\"]+"
}

function macaddress {
	ifconfig `ifwireless` | grep -Po "HWaddr \K[a-fA-F0-9:]+"
}

function ip {
  ifconfig `ifwireless` | grep -Po "inet addr:\K([0-9]{1,3}\.){3}[0-9]{1,3}"
}

function conflicting_macaddress {
	arping -D -I `ifwireless` -c 2 `ip` | grep -Po "\[\K[a-fA-F0-9:]+"
}

function dup_check {
  check_connected

  echo "Checking for duplicate ip (`ip`)..."
  MACADDRESS=$(conflicting_macaddress)
	[[ $MACADDRESS ]] && echo "Duplicate found!! - MAC:[$MACADDRESS]" || echo "No duplicate"
#  arping -D -q -I `ifwireless` -c 2 `ip`
#  [[ "$?" == "0" ]] && echo "No duplicate" || echo "Duplicate IP found"
}

function scan_others {
  check_connected

#  sudo arp-scan -I `ifwireless` --localnet | grep -vi "DUP:"
  sudo arp-scan -I `ifwireless` --localnet
}

function check_connected {
  if [[ -z `ip` ]]; then
    paint yellow "Not connected or no IP assigned"
    echo ""; exit 0
  fi
}

function name_servers {
  if [[ -f /var/lib/dhcp/dhclient.leases ]]; then
    cat /var/lib/dhcp/dhclient.leases | grep -Po "name-servers\K.*" | sed 's/;$//g' | tr -d ' ' | tr -s ',' '\n'
  fi
}

function reset_wifi {
	type rwif >/dev/null 2>&1 || { paint red "Aborting reset: Required 'rwif' command is not installed."; echo ""; exit 1; }
	rwif
	exit 0;
}

function scan_wifis {
  type wscan >/dev/null 2>&1 || { paint red "Aborting scan: Required 'wscan' command is not installed."; echo ""; exit 1; }
  wscan
}

function grep_received_packets {
	file=$1
	cat $file | grep 'received' | sed -re "s/.*([0-9]) received.*/\1/"
}

function grep_packet_loss_percentage {
	file=$1
	cat $file | grep "packet loss" | cut -d' ' -f6 | sed "s/%//g"
}

function check_wifi {
	if [[ $QUICK ]]; then
		paint green "STARTING: Wifi diagnostic QUICK check"
		paint green "  (run 'wifi check --all' for all tests)"
	else
		paint green" STARTING: Wifi diagnostic check"
	fi
	echo ""
	# check wifi radio connection
	paint white "Checking..."
	paint yellow "1. Wifi radio connection..."
	[[ -z $QUICK ]] && sleep 1
	ESSID=$(essid)
	if [[ -z $ESSID || $ESSID =~ off/any ]]; then
		paint red "  PROBLEM: Wifi is not connected or radio is OFF"
		paint red "    Hints: Make sure the wifi radio is ON and a wifi has been selected"
		echo ""; exit 1;
	else
		paint green "  OK: Wifi is connected to '$ESSID' at bit rate `bitrate`"
	fi
	# todo: warnings for low quality and signal strength
	# check wifi address
	paint yellow "2. Localhost IP address..."
	[[ -z $QUICK ]] && sleep 1
	IP=$(ip)
	if [[ -z $IP ]]; then
		paint red "  PROBLEM: No IP address has been assigned to the localhost for this wifi."
		paint red "    Hints: Make sure this host is configured for DHCP.  Reboot wireless router."
		echo ""; exit 1;
	else
		paint green "  OK: IP address ($IP) is assigned"
	fi
	INDEX=3
	# check ip duplications
	if [[ -z $QUICK ]]; then
		paint yellow "$INDEX. Duplicate IP addresses..."
		INDEX=$(($INDEX+1))
		sleep 1
		MACADDRESS=$(conflicting_macaddress)
  	if [[ $MACADDRESS ]]; then
  		paint orange "  WARNING: Another device responded to your IP address - degrades response times."
  		paint orange "    Hints: Reboot wireless router and reconnect to wifi or use a different wifi"
  	else
  		paint green "  OK: No duplicate IP address"
  	fi
  fi
	# check tcp/ip stack
	if [[ -z $QUICK ]]; then
		paint yellow "$INDEX. Local network stack..."
		INDEX=$(($INDEX+1))
		ping -n -i 0.3 -c 6 localhost > $tmpfile
		LOSS=$(grep_packet_loss_percentage $tmpfile)
		if [[ $LOSS == "100" ]]; then
			paint red "  PROBLEM: Unable to reach localhost. Something wrong with local network stack"
			paint red "    Hints: Reboot your machine?"; echo ""; exit 1;
		elif [[ $LOSS != "0" ]]; then
			paint orange "  WARNING: Local network stack is responding, but some attempts failed ($LOSS%)"
		else
			paint green "  OK: Local network stack responding"
		fi
	fi
	# check ping to gateway
	paint yellow "$INDEX. Wireless router IP address..."
	INDEX=$(($INDEX+1))
	[[ -z $QUICK ]] && sleep 1
	GATEWAYIP=$(gateway_ip)
	if [[ -z $GATEWAYIP ]]; then
		paint red "  PROBLEM: No IP for wireless router"
		echo ""; exit 1;
	else
		paint green "  OK: Wireless router located at IP address $GATEWAYIP"
	fi
	paint yellow "$INDEX. Access to wireless router ..."
	INDEX=$(($INDEX+1))
	ping -n -i 0.3 -c 6 $GATEWAYIP > $tmpfile
	LOSS=$(grep_packet_loss_percentage $tmpfile)
	if [[ $LOSS == "100" ]]; then
	  paint red "  PROBLEM: Unable to reach wireless router"
	  paint red "    Hints: Try reconnecting to router and/or rebooting wireless router"
	  echo ""; exit 1;
	elif [[ $LOSS != "0" ]]; then
		paint orange "  WARNING: Wireless router is reachable, but some attempts failed ($LOSS%)"
	else
		paint green "  OK: Wireless router is reachable"
	fi
	# check outer connectivity - ping ip address
	OUTERDOMAIN="yahoo.com"
	OUTERIP=98.138.253.109
	#OUTERDOMAIN="weibo.com"
	#OUTERIP=114.134.80.161
	paint yellow "$INDEX. Access to Internet IP address ($OUTERIP)..."
	INDEX=$(($INDEX+1))
	ping -n -i 0.3 -c 6 $OUTERIP > $tmpfile
	LOSS=$(grep_packet_loss_percentage $tmpfile)
	if [[ $LOSS == "100" ]]; then
		paint red "  PROBLEM: Internet is not reachable via wireless router"
		paint red "    Hints: Reboot wireless router"
		echo ""; exit 1;
	elif [[ $LOSS != "0" ]]; then
		paint orange "  WARNING: Internet is reachable, but some attempts failed ($LOSS%)"	
	else
		paint green "  OK: Internet is reachable"
	fi
	# check dns - ping to yahoo.com (politically uncontraversial address)
	paint yellow "$INDEX. Access to Internet via DNS ($OUTERDOMAIN)..."
	INDEX=$(($INDEX+1))
	ping -n -i 0.3 -c 6 $OUTERDOMAIN > $tmpfile
	LOSS=$(grep_packet_loss_percentage $tmpfile)
	if [[ $LOSS == "100" ]]; then
		paint red "  PROBLEM: Internet is not reachable with DNS"
		paint red "    Hints: A problem with the DNS or DHCP system/firmware. DNS may be temporarily unavailable or try rebooting wireless router"
		echo ""; exit 1;
	elif [[ $LOSS != "0" ]]; then
		paint orange "  WARNING: DNS is working, but some attempts failed ($LOSS%)"	
	else
		paint green "  OK: Internet is reachable via DNS"
	fi
}
QUICK=y
case $1 in
  h | help ) color_usage ;;
  --version) echo $WIFIUTIL_VERSION; exit ;;
  p | ping ) wping $2 ;;
  r | reload | restart | reset) reset_wifi ;;
  g | gateway ) gateway_ip ;;
  d | dup | duplicate )  dup_check ;;
  n | dns ) name_servers ;;
  o | other | others ) scan_others ;;
  c | check )
  	[[ $2 == "-a" || $2 == "--all" ]] && QUICK=
  	check_wifi
  ;;
  ip ) ip ;;
  s | scan ) scan_wifis ;;
  '' )
    check_connected
    paint green "Connected to '`essid`' (`ip`) at `signal`, `bitrate`, Q(`linkquality`%)"
  ;;
  *) color_usage ;;
esac

echo ""