IM IN YR LOOP\n VISIBLE FOO\n IM OUTTA YR LOOP - Der Programmierer-Spamthread #2

[DFYX]

Ich hab mal wieder ein kleines bisschen mit bash rumgespielt. Anlass war, dass ich einen kleinen Portscanner brauchte, der zwischen "Connection refused" und einem Timeout unterscheidet, weil ich ne Firewall, die verbotene Pakete einfach droppt, testen wollte (daher auch die vielen Timeouts im Screenshot). Wer ihn haben will, sei herzlich eingeladen. Für Verbesserungsvorschläge bin ich immer offen. Getestet wurde auf Mac OS X Snow Leopard, aber alle anderen Unixoiden sollten auch gehen.

Code (bash):

#!/bin/bash
 
display_usage()
{
	echo "usage: $(echo $0 | sed "s/^.*\///") host port_from [port_to]"
}
 
# Check parameters
if [ $# -eq 0 ]; then
	display_usage
	exit 1
fi
 
# Setup variables
ADDRESS=$1
FROM=$2
TO=$3
if [ -z "$TO" ]; then
	TO=$2
fi
 
FINISHED=0
TEMPFILE="/tmp/.portscan-temp-$$"
OPEN="/tmp/.portscan-open-$$"
REFUSED="/tmp/.portscan-refused-$$"
TIMEOUT="/tmp/.portscan-timeout-$$"
PID=0
NUM_OPEN=0
NUM_REFUSED=0
NUM_TIMEOUT=0
 
# Setup screen positions
PROGRESS_X=1
PROGRESS_Y=2
PROGRESS_WIDTH=$[$(tput cols) - ${PROGRESS_X} * 2 - 4]
CURRENT_X=3
CURRENT_Y=3
STATUS_X=3
STATUS_Y=5
OPEN_X=3
REFUSED_X=$[($(tput cols) - 15) / 2]
TIMEOUT_X=$[$(tput cols) - ${OPEN_X} * 2 - 15]
PORTS_Y=7
PORTS_HEIGHT=$[$(tput lines) - ${PORTS_Y} - 4]
 
# Create exit handler
trap "exit_handler" EXIT
exit_handler()
{
	# Kill running nc
	if [ "$PID" -gt 0 ]; then
		kill $PID 2>/dev/null
		wait $PID 2>/dev/null
	fi
 
	# Remove temp file
	rm $TEMPFILE
 
	# End on last line
	tput cup $[$(tput lines) + $FINISHED - 2] 0
	printf '\e[0K'
 
	# Restore cursor
	printf '\e[?25h'
	# Restore foreground color
	tput setaf 9
}
 
display_progress()
{
	# Display progress bar
	tput cup ${PROGRESS_Y} ${PROGRESS_X}
	tput setaf 9
	echo -n "[ "
	PROGRESS=$[(1 + ${PORT} - ${FROM}) * ${PROGRESS_WIDTH} / (1 + ${TO} - ${FROM})]
	for ((I=0; I < $PROGRESS; I++)); do
		echo -n "-"
	done
	for ((I=$PROGRESS; I < $PROGRESS_WIDTH; I++)); do
		echo -n " "
	done
	echo " ]"
}
 
display_current()
{
	tput cup ${CURRENT_Y} ${CURRENT_X}
	tput setaf 9
	echo "Currently scanning port $PORT"
}
 
display_ports()
{
	# Display ports header
	tput cup ${PORTS_Y} ${OPEN_X}
	tput setaf 2
	echo -n "Open: ${NUM_OPEN}"
	if [ -f $OPEN ]; then
		I=2
		for P in $(tail -n ${PORTS_HEIGHT} ${OPEN}); do
			tput cup $[${PORTS_Y} + I] ${OPEN_X}
			echo -n $P
			I=$[$I + 1]
		done
	fi
 
	tput cup ${PORTS_Y} ${REFUSED_X}
	tput setaf 3
	echo -n "Refused: ${NUM_REFUSED}"
	if [ -f $REFUSED ]; then
		I=2
		for P in $(tail -n ${PORTS_HEIGHT} ${REFUSED}); do
			tput cup $[${PORTS_Y} + I] ${REFUSED_X}
			echo -n $P
			I=$[$I + 1]
		done
	fi
 
	tput cup ${PORTS_Y} ${TIMEOUT_X}
	tput setaf 1
	echo -n "Timeout: ${NUM_TIMEOUT}"
	if [ -f $TIMEOUT ]; then
		I=2
		for P in $(tail -n ${PORTS_HEIGHT} ${TIMEOUT}); do
			tput cup $[${PORTS_Y} + I] ${TIMEOUT_X}
			echo -n $P
			I=$[$I + 1]
		done
	fi
}
 
# Clear screen and hide cursor
tput clear
printf '\e[?25l'
echo "Scanning $ADDRESS from port $FROM to $TO"
tput cup $[$(tput lines) - 1] 0
echo -n "Cancel with CTRL+C"
 
display_ports
 
for ((PORT=$FROM; PORT <= $TO; PORT++)); do
	display_progress
	display_current
 
	# Scan and display status
	tput cup ${STATUS_Y} ${STATUS_X}
	tput setaf 9
	echo -n "Status: "
	nc -zv $ADDRESS $PORT 2>$TEMPFILE > $TEMPFILE &
	PID=$!
	sleep 1
	kill $PID 2>/dev/null
	wait $PID 2>/dev/null
	RESULT=$(cat $TEMPFILE)
	if grep -qi succeeded $TEMPFILE; then
		tput setaf 2
		printf '\e[0K'
		echo "Found open port $PORT"
		NUM_OPEN=$[$NUM_OPEN + 1]
		echo $PORT >> $OPEN
	elif grep -qi refused $TEMPFILE; then
		tput setaf 3
		printf '\e[0k'
		echo "Connection refused on port $PORT"
		NUM_REFUSED=$[$NUM_REFUSED + 1]
		echo $PORT >> $REFUSED
	else
		NUM_TIMEOUT=$[$NUM_TIMEOUT + 1]
		echo $PORT >> $TIMEOUT
	fi
 
	display_ports
done
 
FINISHED=1

Edit: ich seh grad, dass ich ein paar temporäre Dateien noch nicht automatisch lösch (die, in denen die Ergebnisse stehen), weil ich eigentlich konfigurierbar machen wollte, ob man die behält. Werde ich bei Gelegenheit anpassen.