Programming Forums > Script Programming > Perl

Pizentios · May 23rd, 2006, 5:54 PM

Hey,

for the past few months, i have noticed a increase of invalid login attempts on my webserver (that has ssh running on it). Bascially these are attempts at brute forcing a username and password set....which as many of you know (or at least the ones that hang around on irc or talk to me on MSN) pisses me off. They have never gotten into ssh, but why leave that chance open?

I got talking with IR (Infinite Recursion) about this problem...i soon found out that he also had a problem with these things. Then i found out that he had a script to add these ip's to his host.deny file (sorry windows users, this is a linux/unix only thing). Long story short, i decided to code my own script.

Here it is:

(Toggle Plain Text)

#!/usr/bin/env perl
use Net::SMTP::TLS;
use Switch;
use POSIX;
use Pg;
#use strict;

#Search Patterns:
my @patterns = ("Did not receive identification string","Invalid user","POSSIBLE BREAKIN ATTEMPT");
#db stuff:
#$con_val[0] == the database name.
#$con_val[1] == the host.
#$con_val[2] == the port.
#$con_val[3] == the username for the database.
#$con_val[4] == the password for the database.
my @conn_val = ("sentinel", "localhost", "5432", "sentinel", "fuck_china");

my $ip;
my $date;
my @months;
$months["Jan"] = 0;
$months["Feb"] = 1;
$months["Mar"] = 2;
$months["Apr"] = 3;
$months["May"] = 4;
$months["Jun"] = 5;
$months["Jul"] = 6;
$months["Aug"] = 7;
$months["Sep"] = 8;
$months["Oct"] = 9;
$months["Nov"] = 10;
$months["Dec"] = 11;
my $time = localtime time;
$time =~ m/\b[0-9][0-9][0-9][0-9]\b/;
my $year = $&;
$year -= 2000;
$year += 100;


#connect up to the db.
$conn = Pg::connectdb("host=" . $conn_val[1] . " port=" . $conn_val[2] . " dbname=" . $conn_val[0] . " user=" . $conn_val[3] . " password=" . $conn_val[4]);
#check connection.
if ($conn->status != PGRES_CONNECTION_OK)
{
		die "Failed to connect: ".-$conn->errorMessage."\n";
}
open (TAIL, "tail -f auth.log 2>&1 |") or die "can't open pipe:$!"; 
while (<TAIL>)
{
	switch ($_)
	{
		case m/$patterns[2]/ { next }
		case m/$patterns[0]/
		{
			#log ip, then block and sms details to admin.
			#grab ip addy
			$_ =~ m/\b(?:(?:25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)\.){3}(?:25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)\b/;
			$ip = $&;
			#grab date
			$_ =~ m/\b[A-z]{3} [0-9]{2} [0-9]{1,2}:[0-9]{2}:[0-9]{2}\b/;
			$date = $&;
			#now, chunk date out into, $month, day, hours, minutes, seconds. 
			my ($month, $day, $time) = split(/ /, $date);
			my ($hour, $min, $sec) = split(/:/, $time);
			my $full_date = mktime($sec, $min, $hour, $day, $months[$month], $year);
			my $sql = "INSERT INTO log (ip, date) VALUES ('$ip', $full_date)";
			my $result = $conn->exec($sql);
			open (DENY, ">>", "host.deny") or die "Can't open host.deny!";
			print DENY $ip . "\n";
			close DENY;
		}
		case m/$patterns[1]/
		{
			#get the fucker's ip address.
			$_ =~ m/\b(?:(?:25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)\.){3}(?:25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)\b/;
			$ip = $&;			
			open (CHECK, "tail -n6 auth.log 2>&1 |") or die "can't open pipe:$!";
			my $count = 0;
			while (<CHECK>)
			{
		 	$_ =~ m/\b(?:(?:25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)\.){3}(?:25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)\b/;
				$log_ip = $&;
				if ($log_ip == $ip)
				{
					$count += 1;
				}
			}
			close CHECK;
			if ($count >= 3)
			{
				#we have an attempt.
				#log and ban.
		 	$_ =~ m/\b[A-z]{3} [0-9]{2} [0-9]{1,2}:[0-9]{2}:[0-9]{2}\b/;
				$date = $&;
				my ($month, $day, $time) = split(/ /, $date);
				my ($hour, $min, $sec) = split(/:/, $time);
		 	my $full_date = mktime($sec, $min, $hour, $day, $months[$month], $year);
		 	my $sql = "INSERT INTO log (ip, date) VALUES ('$ip', $full_date)";
				$conn->exec($sql);
				#append to host.deny
		 	open (DENY, ">>", "host.deny") or die "Can't open host.deny!";
				print DENY $ip . "\n";
				close DENY;
			}
		}
	}
} #end of while loop.

#!/usr/bin/env perl
use Net::SMTP::TLS;
use Switch;
use POSIX;
use Pg;
#use strict;

#Search Patterns:
my @patterns = ("Did not receive identification string","Invalid user","POSSIBLE BREAKIN ATTEMPT");
#db stuff:
#$con_val[0] == the database name.
#$con_val[1] == the host.
#$con_val[2] == the port.
#$con_val[3] == the username for the database.
#$con_val[4] == the password for the database.
my @conn_val = ("sentinel", "localhost", "5432", "sentinel", "fuck_china");

my $ip;
my $date;
my @months;
$months["Jan"] = 0;
$months["Feb"] = 1;
$months["Mar"] = 2;
$months["Apr"] = 3;
$months["May"] = 4;
$months["Jun"] = 5;
$months["Jul"] = 6;
$months["Aug"] = 7;
$months["Sep"] = 8;
$months["Oct"] = 9;
$months["Nov"] = 10;
$months["Dec"] = 11;
my $time = localtime time;
$time =~ m/\b[0-9][0-9][0-9][0-9]\b/;
my $year = $&;
$year -= 2000;
$year += 100;


#connect up to the db.
$conn = Pg::connectdb("host=" . $conn_val[1] . " port=" . $conn_val[2] . " dbname=" . $conn_val[0] . " user=" . $conn_val[3] . " password=" . $conn_val[4]);
#check connection.
if ($conn->status != PGRES_CONNECTION_OK)
{
		die "Failed to connect: ".-$conn->errorMessage."\n";
}
open (TAIL, "tail -f auth.log 2>&1 |") or die "can't open pipe:$!"; 
while (<TAIL>)
{
	switch ($_)
	{
		case m/$patterns[2]/ { next }
		case m/$patterns[0]/
		{
			#log ip, then block and sms details to admin.
			#grab ip addy
			$_ =~ m/\b(?:(?:25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)\.){3}(?:25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)\b/;
			$ip = $&;
			#grab date
			$_ =~ m/\b[A-z]{3} [0-9]{2} [0-9]{1,2}:[0-9]{2}:[0-9]{2}\b/;
			$date = $&;
			#now, chunk date out into, $month, day, hours, minutes, seconds. 
			my ($month, $day, $time) = split(/ /, $date);
			my ($hour, $min, $sec) = split(/:/, $time);
			my $full_date = mktime($sec, $min, $hour, $day, $months[$month], $year);
			my $sql = "INSERT INTO log (ip, date) VALUES ('$ip', $full_date)";
			my $result = $conn->exec($sql);
			open (DENY, ">>", "host.deny") or die "Can't open host.deny!";
			print DENY $ip . "\n";
			close DENY;
		}
		case m/$patterns[1]/
		{
			#get the fucker's ip address.
			$_ =~ m/\b(?:(?:25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)\.){3}(?:25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)\b/;
			$ip = $&;			
			open (CHECK, "tail -n6 auth.log 2>&1 |") or die "can't open pipe:$!";
			my $count = 0;
			while (<CHECK>)
			{
		 	$_ =~ m/\b(?:(?:25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)\.){3}(?:25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)\b/;
				$log_ip = $&;
				if ($log_ip == $ip)
				{
					$count += 1;
				}
			}
			close CHECK;
			if ($count >= 3)
			{
				#we have an attempt.
				#log and ban.
		 	$_ =~ m/\b[A-z]{3} [0-9]{2} [0-9]{1,2}:[0-9]{2}:[0-9]{2}\b/;
				$date = $&;
				my ($month, $day, $time) = split(/ /, $date);
				my ($hour, $min, $sec) = split(/:/, $time);
		 	my $full_date = mktime($sec, $min, $hour, $day, $months[$month], $year);
		 	my $sql = "INSERT INTO log (ip, date) VALUES ('$ip', $full_date)";
				$conn->exec($sql);
				#append to host.deny
		 	open (DENY, ">>", "host.deny") or die "Can't open host.deny!";
				print DENY $ip . "\n";
				close DENY;
			}
		}
	}
} #end of while loop.

The code scans your auth.log file, for attempts, adds em to hosts.deny and logs them to a db for furture use. I am now working on making a php script to output a graph based on ip and country code. I have a feeling most attempts will come from china, or atleast a ip that's spoofed to look like china.

I plan on expanding this script's features in the future, so any suggestions would be great. One of the ideas for future features that IR and i were talking about is: adding the ip to a .htaccess file to block the ip from accessing web resources. More programs/log files will be supported in the future.

It should be noted, you'll have to change some of the stuff in the script for it to work on your box (ie: location of auth.log and hosts.deny). Also, i designed this script so that you can (and should) start it from a script at startup.

Infinite Recursion · May 23rd, 2006, 5:59 PM

looks good man, let me know the results

zorin · May 23rd, 2006, 6:29 PM

Nice work Piz, I thought I was the only one with this problem. To be honest, within the first 10mins of starting SSH the log files are filled with invalid passwords too. Im no unix or perl guru so ill have a look at this later.

Ooble · May 23rd, 2006, 6:29 PM

Bad moderator!

* points to the Finished Projects section *

:p

Infinite Recursion · May 23rd, 2006, 11:29 PM

Technically, it may not be "finished" yet

mrynit · May 23rd, 2006, 11:35 PM

WOW, very good. port??

Infinite Recursion · May 24th, 2006, 9:09 AM

Port to what OS?

Pizentios · May 24th, 2006, 9:58 AM

Quote:

Originally Posted by mrynit

WOW, very good. port??

no, it's not a port. This code is all me man. IR helped with some of the ideas and regular expressions.

@Ooble
yeah, i know i could have put it into the finished projects, but as IR said, this thing isn't quite finished yet.

Pizentios · May 24th, 2006, 11:39 AM

hey,

just made a rc script for gentoo to run the perl script:

(Toggle Plain Text)

#!/sbin/runscript
# Copyright 1999-2006 Gentoo Foundation
# Distributed under the terms of the GNU General Public License v2
# $Header: $

depend() {
        before sshd
}

start() {
        start-stop-daemon --start --background --pidfile /var/run/monitor.pid --make-pidfile --exec /usr/scripts/monitor.pl
        eend $?
}

stop() {
        ebegin "Stopping IP Blocker"
        start-stop-daemon --stop --pidfile /var/run/monitor.pid --name /usr/scripts/monitor.pl
        eend $?
}

It should be noted, that this rc script will probably only work on gentoo systems. i still haven't got the stop feature working corectly, but it does start the script at boot once you've added the rc script to a run level (you should add it to the default run level).

Pizentios · May 24th, 2006, 3:07 PM

Hey,

couple fixes. First off, thanks to IR, the stop fuction of the rc script now works. Here's the changes.

(Toggle Plain Text)

stop() {
        ebegin "Stopping IP Blocker"
        kill $(cat /var/run/monitor.pid)
        eend $? "Failed to stop IP Blocker"
}

also, i noticed that there is a chance that the ip could be added to hosts.deny more than once. So i added a if statment to grep hosts.deny for the ip. Here's the new version of the ip blocker.

(Toggle Plain Text)

#!/usr/bin/env perl
use Net::SMTP::TLS;
use Switch;
use POSIX;
use Pg;
#use strict;

#Search Patterns:
my @patterns = ("Did not receive identification string","Invalid user","POSSIBLE BREAKIN ATTEMPT");
#db stuff:
#$con_val[0] == the database name.
#$con_val[1] == the host.
#$con_val[2] == the port.
#$con_val[3] == the username for the database.
#$con_val[4] == the password for the database.
my @conn_val = ("sentinel", "localhost", "5432", "sentinel", "fuck_china*");

my $ip;
my $date;
my @months;
$months["Jan"] = 0;
$months["Feb"] = 1;
$months["Mar"] = 2;
$months["Apr"] = 3;
$months["May"] = 4;
$months["Jun"] = 5;
$months["Jul"] = 6;
$months["Aug"] = 7;
$months["Sep"] = 8;
$months["Oct"] = 9;
$months["Nov"] = 10;
$months["Dec"] = 11;
my $time = localtime time;
$time =~ m/\b[0-9][0-9][0-9][0-9]\b/;
my $year = $&;
$year -= 2000;
$year += 100;


#connect up to the db.
$conn = Pg::connectdb("host=" . $conn_val[1] . " port=" . $conn_val[2] . " dbname=" . $conn_val[0] . " user=" . $conn_val[3] . " password=" . $conn_val[4]);
#check connection.
if ($conn->status != PGRES_CONNECTION_OK)
{
        die "Failed to connect: ".-$conn->errorMessage."\n";
}
open (TAIL, "tail -f /var/log/auth.log 2>&1 |") or die "can't open pipe:$!"; 
while (<TAIL>)
{
	switch ($_)
	{
		case m/$patterns[2]/ { next }
		case m/$patterns[0]/
		{
			#log ip, then block and sms details to admin.
			#grab ip addy
			$_ =~ m/\b(?:(?:25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)\.){3}(?:25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)\b/;
			$ip = $&;
			#grab date
			$_ =~ m/\b[A-z]{3} [0-9]{2} [0-9]{1,2}:[0-9]{2}:[0-9]{2}\b/;
			$date = $&;
			#now, chunk date out into, $month, day, hours, minutes, seconds. 
			my ($month, $day, $time) = split(/ /, $date);
			my ($hour, $min, $sec) = split(/:/, $time);
			my $full_date = mktime($sec, $min, $hour, $day, $months[$month], $year);
			my $sql = "INSERT INTO log (ip, date) VALUES ('$ip', $full_date)";
			my $result = $conn->exec($sql);
			if (system("grep $ip /etc/hosts.deny") != 0)
			{
				open (DENY, ">>", "/etc/hosts.deny") or die "Can't open host.deny!";
				print DENY "ALL: " . $ip . "\n";
				close DENY;
			}
		}
		case m/$patterns[1]/
		{
			#get the fucker's ip address.
			$_ =~ m/\b(?:(?:25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)\.){3}(?:25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)\b/;
			$ip = $&;			
			open (CHECK, "tail -n6 /var/log/auth.log 2>&1 |") or die "can't open pipe:$!";
			my $count = 0;
			while (<CHECK>)
			{
				$_ =~ m/\b(?:(?:25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)\.){3}(?:25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)\b/;
				$log_ip = $&;
				if ($log_ip == $ip)
				{
					$count += 1;
				}
			}
			close CHECK;
			if ($count >= 3)
			{
				#we have an attempt.
				#log and ban.
				$_ =~ m/\b[A-z]{3} [0-9]{2} [0-9]{1,2}:[0-9]{2}:[0-9]{2}\b/;
				$date = $&;
				my ($month, $day, $time) = split(/ /, $date);
				my ($hour, $min, $sec) = split(/:/, $time);
				my $full_date = mktime($sec, $min, $hour, $day, $months[$month], $year);
				my $sql = "INSERT INTO log (ip, date) VALUES ('$ip', $full_date)";
				$conn->exec($sql);
				#append to host.deny
				if (system("grep $ip /etc/hosts.deny") != 0)
				{
					open (DENY, ">>", "/etc/hosts.deny") or die "Can't open host.deny!";
					print DENY "ALL: " . $ip . "\n";
					close DENY;
				}
			}
		}
	}
} #end of while loop.

#!/usr/bin/env perl
use Net::SMTP::TLS;
use Switch;
use POSIX;
use Pg;
#use strict;

#Search Patterns:
my @patterns = ("Did not receive identification string","Invalid user","POSSIBLE BREAKIN ATTEMPT");
#db stuff:
#$con_val[0] == the database name.
#$con_val[1] == the host.
#$con_val[2] == the port.
#$con_val[3] == the username for the database.
#$con_val[4] == the password for the database.
my @conn_val = ("sentinel", "localhost", "5432", "sentinel", "fuck_china*");

my $ip;
my $date;
my @months;
$months["Jan"] = 0;
$months["Feb"] = 1;
$months["Mar"] = 2;
$months["Apr"] = 3;
$months["May"] = 4;
$months["Jun"] = 5;
$months["Jul"] = 6;
$months["Aug"] = 7;
$months["Sep"] = 8;
$months["Oct"] = 9;
$months["Nov"] = 10;
$months["Dec"] = 11;
my $time = localtime time;
$time =~ m/\b[0-9][0-9][0-9][0-9]\b/;
my $year = $&;
$year -= 2000;
$year += 100;


#connect up to the db.
$conn = Pg::connectdb("host=" . $conn_val[1] . " port=" . $conn_val[2] . " dbname=" . $conn_val[0] . " user=" . $conn_val[3] . " password=" . $conn_val[4]);
#check connection.
if ($conn->status != PGRES_CONNECTION_OK)
{
        die "Failed to connect: ".-$conn->errorMessage."\n";
}
open (TAIL, "tail -f /var/log/auth.log 2>&1 |") or die "can't open pipe:$!"; 
while (<TAIL>)
{
	switch ($_)
	{
		case m/$patterns[2]/ { next }
		case m/$patterns[0]/
		{
			#log ip, then block and sms details to admin.
			#grab ip addy
			$_ =~ m/\b(?:(?:25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)\.){3}(?:25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)\b/;
			$ip = $&;
			#grab date
			$_ =~ m/\b[A-z]{3} [0-9]{2} [0-9]{1,2}:[0-9]{2}:[0-9]{2}\b/;
			$date = $&;
			#now, chunk date out into, $month, day, hours, minutes, seconds. 
			my ($month, $day, $time) = split(/ /, $date);
			my ($hour, $min, $sec) = split(/:/, $time);
			my $full_date = mktime($sec, $min, $hour, $day, $months[$month], $year);
			my $sql = "INSERT INTO log (ip, date) VALUES ('$ip', $full_date)";
			my $result = $conn->exec($sql);
			if (system("grep $ip /etc/hosts.deny") != 0)
			{
				open (DENY, ">>", "/etc/hosts.deny") or die "Can't open host.deny!";
				print DENY "ALL: " . $ip . "\n";
				close DENY;
			}
		}
		case m/$patterns[1]/
		{
			#get the fucker's ip address.
			$_ =~ m/\b(?:(?:25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)\.){3}(?:25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)\b/;
			$ip = $&;			
			open (CHECK, "tail -n6 /var/log/auth.log 2>&1 |") or die "can't open pipe:$!";
			my $count = 0;
			while (<CHECK>)
			{
				$_ =~ m/\b(?:(?:25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)\.){3}(?:25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)\b/;
				$log_ip = $&;
				if ($log_ip == $ip)
				{
					$count += 1;
				}
			}
			close CHECK;
			if ($count >= 3)
			{
				#we have an attempt.
				#log and ban.
				$_ =~ m/\b[A-z]{3} [0-9]{2} [0-9]{1,2}:[0-9]{2}:[0-9]{2}\b/;
				$date = $&;
				my ($month, $day, $time) = split(/ /, $date);
				my ($hour, $min, $sec) = split(/:/, $time);
				my $full_date = mktime($sec, $min, $hour, $day, $months[$month], $year);
				my $sql = "INSERT INTO log (ip, date) VALUES ('$ip', $full_date)";
				$conn->exec($sql);
				#append to host.deny
				if (system("grep $ip /etc/hosts.deny") != 0)
				{
					open (DENY, ">>", "/etc/hosts.deny") or die "Can't open host.deny!";
					print DENY "ALL: " . $ip . "\n";
					close DENY;
				}
			}
		}
	}
} #end of while loop.

May 23rd, 2006, 5:54 PM	#1
Pizentios Programming Guru Join Date: May 2004 Location: Brandon, Manitoba, Canada Posts: 2,023 Rep Power: 7	IP blocker Hey, for the past few months, i have noticed a increase of invalid login attempts on my webserver (that has ssh running on it). Bascially these are attempts at brute forcing a username and password set....which as many of you know (or at least the ones that hang around on irc or talk to me on MSN) pisses me off. They have never gotten into ssh, but why leave that chance open? I got talking with IR (Infinite Recursion) about this problem...i soon found out that he also had a problem with these things. Then i found out that he had a script to add these ip's to his host.deny file (sorry windows users, this is a linux/unix only thing). Long story short, i decided to code my own script. Here it is: (Toggle Plain Text) #!/usr/bin/env perl use Net::SMTP::TLS; use Switch; use POSIX; use Pg; #use strict; #Search Patterns: my @patterns = ("Did not receive identification string","Invalid user","POSSIBLE BREAKIN ATTEMPT"); #db stuff: #$con_val[0] == the database name. #$con_val[1] == the host. #$con_val[2] == the port. #$con_val[3] == the username for the database. #$con_val[4] == the password for the database. my @conn_val = ("sentinel", "localhost", "5432", "sentinel", "fuck_china"); my $ip; my $date; my @months; $months["Jan"] = 0; $months["Feb"] = 1; $months["Mar"] = 2; $months["Apr"] = 3; $months["May"] = 4; $months["Jun"] = 5; $months["Jul"] = 6; $months["Aug"] = 7; $months["Sep"] = 8; $months["Oct"] = 9; $months["Nov"] = 10; $months["Dec"] = 11; my $time = localtime time; $time =~ m/\b[0-9][0-9][0-9][0-9]\b/; my $year = $&; $year -= 2000; $year += 100; #connect up to the db. $conn = Pg::connectdb("host=" . $conn_val[1] . " port=" . $conn_val[2] . " dbname=" . $conn_val[0] . " user=" . $conn_val[3] . " password=" . $conn_val[4]); #check connection. if ($conn->status != PGRES_CONNECTION_OK) { die "Failed to connect: ".-$conn->errorMessage."\n"; } open (TAIL, "tail -f auth.log 2>&1 \|") or die "can't open pipe:$!"; while (<TAIL>) { switch ($_) { case m/$patterns[2]/ { next } case m/$patterns[0]/ { #log ip, then block and sms details to admin. #grab ip addy $_ =~ m/\b(?:(?:25[0-5]\|2[0-4][0-9]\|[01]?[0-9][0-9]?)\.){3}(?:25[0-5]\|2[0-4][0-9]\|[01]?[0-9][0-9]?)\b/; $ip = $&; #grab date $_ =~ m/\b[A-z]{3} [0-9]{2} [0-9]{1,2}:[0-9]{2}:[0-9]{2}\b/; $date = $&; #now, chunk date out into, $month, day, hours, minutes, seconds. my ($month, $day, $time) = split(/ /, $date); my ($hour, $min, $sec) = split(/:/, $time); my $full_date = mktime($sec, $min, $hour, $day, $months[$month], $year); my $sql = "INSERT INTO log (ip, date) VALUES ('$ip', $full_date)"; my $result = $conn->exec($sql); open (DENY, ">>", "host.deny") or die "Can't open host.deny!"; print DENY $ip . "\n"; close DENY; } case m/$patterns[1]/ { #get the fucker's ip address. $_ =~ m/\b(?:(?:25[0-5]\|2[0-4][0-9]\|[01]?[0-9][0-9]?)\.){3}(?:25[0-5]\|2[0-4][0-9]\|[01]?[0-9][0-9]?)\b/; $ip = $&; open (CHECK, "tail -n6 auth.log 2>&1 \|") or die "can't open pipe:$!"; my $count = 0; while (<CHECK>) { $_ =~ m/\b(?:(?:25[0-5]\|2[0-4][0-9]\|[01]?[0-9][0-9]?)\.){3}(?:25[0-5]\|2[0-4][0-9]\|[01]?[0-9][0-9]?)\b/; $log_ip = $&; if ($log_ip == $ip) { $count += 1; } } close CHECK; if ($count >= 3) { #we have an attempt. #log and ban. $_ =~ m/\b[A-z]{3} [0-9]{2} [0-9]{1,2}:[0-9]{2}:[0-9]{2}\b/; $date = $&; my ($month, $day, $time) = split(/ /, $date); my ($hour, $min, $sec) = split(/:/, $time); my $full_date = mktime($sec, $min, $hour, $day, $months[$month], $year); my $sql = "INSERT INTO log (ip, date) VALUES ('$ip', $full_date)"; $conn->exec($sql); #append to host.deny open (DENY, ">>", "host.deny") or die "Can't open host.deny!"; print DENY $ip . "\n"; close DENY; } } } } #end of while loop. #!/usr/bin/env perl use Net::SMTP::TLS; use Switch; use POSIX; use Pg; #use strict; #Search Patterns: my @patterns = ("Did not receive identification string","Invalid user","POSSIBLE BREAKIN ATTEMPT"); #db stuff: #$con_val[0] == the database name. #$con_val[1] == the host. #$con_val[2] == the port. #$con_val[3] == the username for the database. #$con_val[4] == the password for the database. my @conn_val = ("sentinel", "localhost", "5432", "sentinel", "fuck_china"); my $ip; my $date; my @months; $months["Jan"] = 0; $months["Feb"] = 1; $months["Mar"] = 2; $months["Apr"] = 3; $months["May"] = 4; $months["Jun"] = 5; $months["Jul"] = 6; $months["Aug"] = 7; $months["Sep"] = 8; $months["Oct"] = 9; $months["Nov"] = 10; $months["Dec"] = 11; my $time = localtime time; $time =~ m/\b[0-9][0-9][0-9][0-9]\b/; my $year = $&; $year -= 2000; $year += 100; #connect up to the db. $conn = Pg::connectdb("host=" . $conn_val[1] . " port=" . $conn_val[2] . " dbname=" . $conn_val[0] . " user=" . $conn_val[3] . " password=" . $conn_val[4]); #check connection. if ($conn->status != PGRES_CONNECTION_OK) { die "Failed to connect: ".-$conn->errorMessage."\n"; } open (TAIL, "tail -f auth.log 2>&1 \|") or die "can't open pipe:$!"; while (<TAIL>) { switch ($_) { case m/$patterns[2]/ { next } case m/$patterns[0]/ { #log ip, then block and sms details to admin. #grab ip addy $_ =~ m/\b(?:(?:25[0-5]\|2[0-4][0-9]\|[01]?[0-9][0-9]?)\.){3}(?:25[0-5]\|2[0-4][0-9]\|[01]?[0-9][0-9]?)\b/; $ip = $&; #grab date $_ =~ m/\b[A-z]{3} [0-9]{2} [0-9]{1,2}:[0-9]{2}:[0-9]{2}\b/; $date = $&; #now, chunk date out into, $month, day, hours, minutes, seconds. my ($month, $day, $time) = split(/ /, $date); my ($hour, $min, $sec) = split(/:/, $time); my $full_date = mktime($sec, $min, $hour, $day, $months[$month], $year); my $sql = "INSERT INTO log (ip, date) VALUES ('$ip', $full_date)"; my $result = $conn->exec($sql); open (DENY, ">>", "host.deny") or die "Can't open host.deny!"; print DENY $ip . "\n"; close DENY; } case m/$patterns[1]/ { #get the fucker's ip address. $_ =~ m/\b(?:(?:25[0-5]\|2[0-4][0-9]\|[01]?[0-9][0-9]?)\.){3}(?:25[0-5]\|2[0-4][0-9]\|[01]?[0-9][0-9]?)\b/; $ip = $&; open (CHECK, "tail -n6 auth.log 2>&1 \|") or die "can't open pipe:$!"; my $count = 0; while (<CHECK>) { $_ =~ m/\b(?:(?:25[0-5]\|2[0-4][0-9]\|[01]?[0-9][0-9]?)\.){3}(?:25[0-5]\|2[0-4][0-9]\|[01]?[0-9][0-9]?)\b/; $log_ip = $&; if ($log_ip == $ip) { $count += 1; } } close CHECK; if ($count >= 3) { #we have an attempt. #log and ban. $_ =~ m/\b[A-z]{3} [0-9]{2} [0-9]{1,2}:[0-9]{2}:[0-9]{2}\b/; $date = $&; my ($month, $day, $time) = split(/ /, $date); my ($hour, $min, $sec) = split(/:/, $time); my $full_date = mktime($sec, $min, $hour, $day, $months[$month], $year); my $sql = "INSERT INTO log (ip, date) VALUES ('$ip', $full_date)"; $conn->exec($sql); #append to host.deny open (DENY, ">>", "host.deny") or die "Can't open host.deny!"; print DENY $ip . "\n"; close DENY; } } } } #end of while loop. The code scans your auth.log file, for attempts, adds em to hosts.deny and logs them to a db for furture use. I am now working on making a php script to output a graph based on ip and country code. I have a feeling most attempts will come from china, or atleast a ip that's spoofed to look like china. I plan on expanding this script's features in the future, so any suggestions would be great. One of the ideas for future features that IR and i were talking about is: adding the ip to a .htaccess file to block the ip from accessing web resources. More programs/log files will be supported in the future. It should be noted, you'll have to change some of the stuff in the script for it to work on your box (ie: location of auth.log and hosts.deny). Also, i designed this script so that you can (and should) start it from a script at startup. __________________ Profanity is the one language that all programmers understand. Check out my Blog <---updated Nov 30 2007!

May 23rd, 2006, 5:59 PM	#2
Infinite Recursion Programming Guru Join Date: Jul 2004 Location: United States Posts: 3,467 Rep Power: 8	looks good man, let me know the results __________________ http://jasonpowers.net "There are a thousand hacking at the branches of evil to one who is striking at the root."

May 23rd, 2006, 6:29 PM	#4
Ooble I eat cake for breakfast. Join Date: Jul 2004 Location: In my box. Posts: 4,434 Rep Power: 9	Bad moderator! * points to the Finished Projects section * :p __________________ Me :: You :: Them

May 23rd, 2006, 11:29 PM	#5
Infinite Recursion Programming Guru Join Date: Jul 2004 Location: United States Posts: 3,467 Rep Power: 8	Technically, it may not be "finished" yet __________________ http://jasonpowers.net "There are a thousand hacking at the branches of evil to one who is striking at the root."

May 23rd, 2006, 11:35 PM	#6
mrynit Hobbyist Programmer Join Date: Mar 2006 Location: WA, USA Posts: 340 Rep Power: 3	WOW, very good. port?? __________________ i dont know much about programming but i try to help

May 23rd, 2006, 6:29 PM	#3
zorin Hobbyist Programmer Join Date: Apr 2005 Posts: 218 Rep Power: 4	Nice work Piz, I thought I was the only one with this problem. To be honest, within the first 10mins of starting SSH the log files are filled with invalid passwords too. Im no unix or perl guru so ill have a look at this later.

May 24th, 2006, 9:09 AM	#7
Infinite Recursion Programming Guru Join Date: Jul 2004 Location: United States Posts: 3,467 Rep Power: 8	Port to what OS? __________________ http://jasonpowers.net "There are a thousand hacking at the branches of evil to one who is striking at the root."

May 24th, 2006, 11:39 AM	#9
Pizentios Programming Guru Join Date: May 2004 Location: Brandon, Manitoba, Canada Posts: 2,023 Rep Power: 7	hey, just made a rc script for gentoo to run the perl script: (Toggle Plain Text) #!/sbin/runscript # Copyright 1999-2006 Gentoo Foundation # Distributed under the terms of the GNU General Public License v2 # $Header: $ depend() { before sshd } start() { start-stop-daemon --start --background --pidfile /var/run/monitor.pid --make-pidfile --exec /usr/scripts/monitor.pl eend $? } stop() { ebegin "Stopping IP Blocker" start-stop-daemon --stop --pidfile /var/run/monitor.pid --name /usr/scripts/monitor.pl eend $? } #!/sbin/runscript # Copyright 1999-2006 Gentoo Foundation # Distributed under the terms of the GNU General Public License v2 # $Header: $ depend() { before sshd } start() { start-stop-daemon --start --background --pidfile /var/run/monitor.pid --make-pidfile --exec /usr/scripts/monitor.pl eend $? } stop() { ebegin "Stopping IP Blocker" start-stop-daemon --stop --pidfile /var/run/monitor.pid --name /usr/scripts/monitor.pl eend $? } It should be noted, that this rc script will probably only work on gentoo systems. i still haven't got the stop feature working corectly, but it does start the script at boot once you've added the rc script to a run level (you should add it to the default run level). __________________ Profanity is the one language that all programmers understand. Check out my Blog <---updated Nov 30 2007!

May 24th, 2006, 3:07 PM	#10
Pizentios Programming Guru Join Date: May 2004 Location: Brandon, Manitoba, Canada Posts: 2,023 Rep Power: 7	Hey, couple fixes. First off, thanks to IR, the stop fuction of the rc script now works. Here's the changes. (Toggle Plain Text) stop() { ebegin "Stopping IP Blocker" kill $(cat /var/run/monitor.pid) eend $? "Failed to stop IP Blocker" } stop() { ebegin "Stopping IP Blocker" kill $(cat /var/run/monitor.pid) eend $? "Failed to stop IP Blocker" } also, i noticed that there is a chance that the ip could be added to hosts.deny more than once. So i added a if statment to grep hosts.deny for the ip. Here's the new version of the ip blocker. (Toggle Plain Text) #!/usr/bin/env perl use Net::SMTP::TLS; use Switch; use POSIX; use Pg; #use strict; #Search Patterns: my @patterns = ("Did not receive identification string","Invalid user","POSSIBLE BREAKIN ATTEMPT"); #db stuff: #$con_val[0] == the database name. #$con_val[1] == the host. #$con_val[2] == the port. #$con_val[3] == the username for the database. #$con_val[4] == the password for the database. my @conn_val = ("sentinel", "localhost", "5432", "sentinel", "fuck_china"); my $ip; my $date; my @months; $months["Jan"] = 0; $months["Feb"] = 1; $months["Mar"] = 2; $months["Apr"] = 3; $months["May"] = 4; $months["Jun"] = 5; $months["Jul"] = 6; $months["Aug"] = 7; $months["Sep"] = 8; $months["Oct"] = 9; $months["Nov"] = 10; $months["Dec"] = 11; my $time = localtime time; $time =~ m/\b[0-9][0-9][0-9][0-9]\b/; my $year = $&; $year -= 2000; $year += 100; #connect up to the db. $conn = Pg::connectdb("host=" . $conn_val[1] . " port=" . $conn_val[2] . " dbname=" . $conn_val[0] . " user=" . $conn_val[3] . " password=" . $conn_val[4]); #check connection. if ($conn->status != PGRES_CONNECTION_OK) { die "Failed to connect: ".-$conn->errorMessage."\n"; } open (TAIL, "tail -f /var/log/auth.log 2>&1 \|") or die "can't open pipe:$!"; while (<TAIL>) { switch ($_) { case m/$patterns[2]/ { next } case m/$patterns[0]/ { #log ip, then block and sms details to admin. #grab ip addy $_ =~ m/\b(?:(?:25[0-5]\|2[0-4][0-9]\|[01]?[0-9][0-9]?)\.){3}(?:25[0-5]\|2[0-4][0-9]\|[01]?[0-9][0-9]?)\b/; $ip = $&; #grab date $_ =~ m/\b[A-z]{3} [0-9]{2} [0-9]{1,2}:[0-9]{2}:[0-9]{2}\b/; $date = $&; #now, chunk date out into, $month, day, hours, minutes, seconds. my ($month, $day, $time) = split(/ /, $date); my ($hour, $min, $sec) = split(/:/, $time); my $full_date = mktime($sec, $min, $hour, $day, $months[$month], $year); my $sql = "INSERT INTO log (ip, date) VALUES ('$ip', $full_date)"; my $result = $conn->exec($sql); if (system("grep $ip /etc/hosts.deny") != 0) { open (DENY, ">>", "/etc/hosts.deny") or die "Can't open host.deny!"; print DENY "ALL: " . $ip . "\n"; close DENY; } } case m/$patterns[1]/ { #get the fucker's ip address. $_ =~ m/\b(?:(?:25[0-5]\|2[0-4][0-9]\|[01]?[0-9][0-9]?)\.){3}(?:25[0-5]\|2[0-4][0-9]\|[01]?[0-9][0-9]?)\b/; $ip = $&; open (CHECK, "tail -n6 /var/log/auth.log 2>&1 \|") or die "can't open pipe:$!"; my $count = 0; while (<CHECK>) { $_ =~ m/\b(?:(?:25[0-5]\|2[0-4][0-9]\|[01]?[0-9][0-9]?)\.){3}(?:25[0-5]\|2[0-4][0-9]\|[01]?[0-9][0-9]?)\b/; $log_ip = $&; if ($log_ip == $ip) { $count += 1; } } close CHECK; if ($count >= 3) { #we have an attempt. #log and ban. $_ =~ m/\b[A-z]{3} [0-9]{2} [0-9]{1,2}:[0-9]{2}:[0-9]{2}\b/; $date = $&; my ($month, $day, $time) = split(/ /, $date); my ($hour, $min, $sec) = split(/:/, $time); my $full_date = mktime($sec, $min, $hour, $day, $months[$month], $year); my $sql = "INSERT INTO log (ip, date) VALUES ('$ip', $full_date)"; $conn->exec($sql); #append to host.deny if (system("grep $ip /etc/hosts.deny") != 0) { open (DENY, ">>", "/etc/hosts.deny") or die "Can't open host.deny!"; print DENY "ALL: " . $ip . "\n"; close DENY; } } } } } #end of while loop. #!/usr/bin/env perl use Net::SMTP::TLS; use Switch; use POSIX; use Pg; #use strict; #Search Patterns: my @patterns = ("Did not receive identification string","Invalid user","POSSIBLE BREAKIN ATTEMPT"); #db stuff: #$con_val[0] == the database name. #$con_val[1] == the host. #$con_val[2] == the port. #$con_val[3] == the username for the database. #$con_val[4] == the password for the database. my @conn_val = ("sentinel", "localhost", "5432", "sentinel", "fuck_china"); my $ip; my $date; my @months; $months["Jan"] = 0; $months["Feb"] = 1; $months["Mar"] = 2; $months["Apr"] = 3; $months["May"] = 4; $months["Jun"] = 5; $months["Jul"] = 6; $months["Aug"] = 7; $months["Sep"] = 8; $months["Oct"] = 9; $months["Nov"] = 10; $months["Dec"] = 11; my $time = localtime time; $time =~ m/\b[0-9][0-9][0-9][0-9]\b/; my $year = $&; $year -= 2000; $year += 100; #connect up to the db. $conn = Pg::connectdb("host=" . $conn_val[1] . " port=" . $conn_val[2] . " dbname=" . $conn_val[0] . " user=" . $conn_val[3] . " password=" . $conn_val[4]); #check connection. if ($conn->status != PGRES_CONNECTION_OK) { die "Failed to connect: ".-$conn->errorMessage."\n"; } open (TAIL, "tail -f /var/log/auth.log 2>&1 \|") or die "can't open pipe:$!"; while (<TAIL>) { switch ($_) { case m/$patterns[2]/ { next } case m/$patterns[0]/ { #log ip, then block and sms details to admin. #grab ip addy $_ =~ m/\b(?:(?:25[0-5]\|2[0-4][0-9]\|[01]?[0-9][0-9]?)\.){3}(?:25[0-5]\|2[0-4][0-9]\|[01]?[0-9][0-9]?)\b/; $ip = $&; #grab date $_ =~ m/\b[A-z]{3} [0-9]{2} [0-9]{1,2}:[0-9]{2}:[0-9]{2}\b/; $date = $&; #now, chunk date out into, $month, day, hours, minutes, seconds. my ($month, $day, $time) = split(/ /, $date); my ($hour, $min, $sec) = split(/:/, $time); my $full_date = mktime($sec, $min, $hour, $day, $months[$month], $year); my $sql = "INSERT INTO log (ip, date) VALUES ('$ip', $full_date)"; my $result = $conn->exec($sql); if (system("grep $ip /etc/hosts.deny") != 0) { open (DENY, ">>", "/etc/hosts.deny") or die "Can't open host.deny!"; print DENY "ALL: " . $ip . "\n"; close DENY; } } case m/$patterns[1]/ { #get the fucker's ip address. $_ =~ m/\b(?:(?:25[0-5]\|2[0-4][0-9]\|[01]?[0-9][0-9]?)\.){3}(?:25[0-5]\|2[0-4][0-9]\|[01]?[0-9][0-9]?)\b/; $ip = $&; open (CHECK, "tail -n6 /var/log/auth.log 2>&1 \|") or die "can't open pipe:$!"; my $count = 0; while (<CHECK>) { $_ =~ m/\b(?:(?:25[0-5]\|2[0-4][0-9]\|[01]?[0-9][0-9]?)\.){3}(?:25[0-5]\|2[0-4][0-9]\|[01]?[0-9][0-9]?)\b/; $log_ip = $&; if ($log_ip == $ip) { $count += 1; } } close CHECK; if ($count >= 3) { #we have an attempt. #log and ban. $_ =~ m/\b[A-z]{3} [0-9]{2} [0-9]{1,2}:[0-9]{2}:[0-9]{2}\b/; $date = $&; my ($month, $day, $time) = split(/ /, $date); my ($hour, $min, $sec) = split(/:/, $time); my $full_date = mktime($sec, $min, $hour, $day, $months[$month], $year); my $sql = "INSERT INTO log (ip, date) VALUES ('$ip', $full_date)"; $conn->exec($sql); #append to host.deny if (system("grep $ip /etc/hosts.deny") != 0) { open (DENY, ">>", "/etc/hosts.deny") or die "Can't open host.deny!"; print DENY "ALL: " . $ip . "\n"; close DENY; } } } } } #end of while loop. __________________ Profanity is the one language that all programmers understand. Check out my Blog <---updated Nov 30 2007! Last edited by Pizentios; May 24th, 2006 at 3:57 PM.

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IP blocker