#!/bin/sh
#Ping Radar : ping a list of hosts and display response time
#Copyright (C) 2016 Weber Yann
#
#This program is free software; you can redistribute it and/or modify
#it under the terms of the GNU General Public License as published by
#the Free Software Foundation; either version 3 of the License, or
#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 General Public License for more details.
#
#You should have received a copy of the GNU General Public License
#along with this program.  If not, see <http://www.gnu.org/licenses/>.
alias echo='/bin/echo -e'

REFRESH=2
verbose=0
res_file=$(mktemp -t hosts_scanner.XXXXXXXXXX)
date_cmd="date --rfc-3339=s"

lock="${res_file}.lock"

pids=""
clean_exit() {
	clear
	reset
	echo "Ctrl+C pressed, exiting..."
	for pid in $(echo $pids)
	do
		echo killing $pid
		kill $pid 2>/dev/null
	done
	wait $(echo $pids)
	rmdir ${res_file}.lock 2>/dev/null
	rm -v $res_file
	exit 0
}

cidr_nmap_pid=""
cidr_nmap_res=""
cidr_pids=""
clean_cidr() {
	echo "CIDR killed, cleaning..."

	kill $cidr_nmap_pid 2>/dev/null

	for pid in $(echo $cidr_pids $cidr_nmap_pid)
	do
		echo CIDR killing $pid
		kill $pid 2>/dev/null
	done
	wait $(echo $cidr_pids $cidr_nmap_pid)
	rm -v $cidr_nmap_res
	exit 0
}

semlock() {
	while [ 1 ]
	do
		mkdir $1 2>/dev/null && break
	done
}

semrelease() {
	rmdir $1
}

upd_ping() {
	# update ping stat file
	# $1 host
	# $2 file
	# $3 lock
	# $4 delay

	lock="$3"
	test -z "$4" && delay=5 || delay=$4
	last_up="never"
	
	while [ 1 ]
	do
		rep=$(ping -qc 1 $1 2>/dev/null  )
		ret=$?
		rep=$(echo $rep | sed -nE 's/.*rtt min\/avg\/max\/mdev = [0-9]+\.[0-9]+\/([0-9]+\.[0-9]+)\/.*$/\1/p')
		rehost=$(echo $h|sed 's/\./\\./g')

		semlock $lock


		if [ $ret -eq 0 ]
		then
			last_up=$($date_cmd)
			#echo "${res}$rep $hstr $last_up" >> $2
		else
			rep="down"
			#echo "${res}down $hstr $last_up" >> $2
		fi

		sed -i "s/^\\s*$rehost\\s.*$/$(printf "%30s %8s %30s\n" $1 $rep "$last_up")/" "$2"

		semrelease $lock

		sleep $delay
	done
}

cidr_scan() {
	# cidr ping scan
	# $1 cidr
	# $2 result file
	# $3 lock
	# $4 delay

	test -z "$4" && delay=5 || delay=$4
	cidr_nmap_res=$(mktemp -t ping_radar_cidr_nmap.XXXXXXXX)
	nmap_cmd="nmap -sP -oG $cidr_nmap_res --max-rate=15 --max-hostgroup=5 $1"

	trap clean_cidr 15

	#nmap -sP -oG "$cidr_nmap_res" $1 >/dev/null &
	$nmap_cmd >/dev/null &
	cidr_nmap_pid=$!

	while [ 1 ]
	do
		if kill -0 $cidr_nmap_pid 2> /dev/null
		then
			semlock $lock
			echo "CIDR scanning $1" >&2
			semrelease $lock
			rerun=0
		else
			semlock $lock
			echo "CIDR scanned $1" >&2
			semrelease $lock
			rerun=1
		fi
		
		for h in $(cat $cidr_nmap_res | grep "Up$" | cut -d " " -f 2)
		do
			rehost=$(echo $h|sed 's/\./\\./g')
			if grep " $rehost " $2 > /dev/null
			then
				continue
			else
				printf "%30s %8s %30s\n" $h "unknw" "unknwn" >> $res_file
				upd_ping $h $2 $3 &
				pid=$!
				cidr_pids="${cidr_pids}\n$pid"

				semlock $lock
				echo "$pid scanning $h" >&2
				semrelease $lock
			fi
		done

		sleep $delay
		if [ $rerun -eq 1 ]
		then
			$nmap_cmd >/dev/null &
			cidr_nmap_pid=$!
		fi
	done
}

usage() {
	echo "Usage : $0 [-c CONFIG_FILE] [-i HOST [-i HOST [...]]]" >&2
}

while getopts c:i: o
do
	case $o in
	c)
		HOSTS_FILES="$OPTARG";;
	*)	usage; exit 1;;
	esac
done

if [ -z "$HOSTS_FILES" ]
then
	HOSTS_FILES="$HOME/.hosts_scanner"
fi

if [ ! -f "$HOSTS_FILES" ]
then
	echo "File '$HOSTS_FILES' not found" >&4
	usage
	exit 2
fi

trap clean_exit 2

# prepopulate file
for h in $(cat "$HOSTS_FILES")
do
	if echo $h |grep -v '/' > /dev/null
	then
		printf "%30s %8s %30s\n" $h "unknw" "unknwn" >> $res_file
	fi
done

# run scanners
for h in $(cat "$HOSTS_FILES" )
do
	if echo $h |grep -v '/' > /dev/null
	then
		upd_ping $h $res_file $lock 5 &
	else
		# cidr scan
		cidr_scan $h $res_file $lock 10 &
	fi
	pid=$!
	pids="${pids}\n$pid"
	echo "$h updated by $pid" >&2
done
sleep 1

loop_count=0
while [ 1 ]
do
	#sleep 1
	#continue

	semlock $lock
	#clear
	loop_count=$(expr $loop_count + 1)
	if [ $loop_count = "5" ]
	then
		clear;
		loop_count=0
	fi
	echo -e "\x1B[0;0HPing radar $($date_cmd)\n$(printf "%30s %8s %30s\n" "host" "ping" "last up")\n$(for i in $(seq 70); do echo -n "="; done)\n$(sed -E -e "s/\snever$/$(tput sgr0)\0/" -e "s/^.* down .*$/$(tput setaf 1)\0$(tput sgr0)/"  $res_file)"

#	echo "Ping radar $($date_cmd)\n"
#	printf "%30s %8s %30s\n" "host" "ping" "last up"
#	for i in $(seq 70); do echo -n "="; done
#	echo ""
#
#	#cat $res_file
#
#	#grep -v " down " $res_file
#	#grep " down " $res_file
#
#	sed -E -e "s/\snever$/$(tput sgr0)\0/" -e "s/^.* down .*$/$(tput setaf 1)\0$(tput sgr0)/"  $res_file

	semrelease $lock
	sleep $REFRESH
done